Friday, 30 December 2016


For anyone trying to work out why Microsoft Exchange Push notification message responses are not being accepted by the server, it has taken me a while, but it seems to be that it does not accept a "chunked" response.

We were sending a response from a CGI script from apache, and that is normally chunked.

But there is no way to guess what is wrong. Lots of examples on the Internet, but none worked.

We were sending text/xml with :-

<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns="">
<SendNotificationResult xmlns="">

I tried every combination of xmlns tagging and all sorts, eventually solved the problem by sending with a Content-Length rather than chunked. That is what it wanted.


But I guess it is in line with the rest of the documentation, which is pretty crap (in my opinion), e.g. one page listing a field as URL in one place and Url in another, and we had the wrong one. You just have to guess what is wrong half the time.

Anyway, this blog is for those looking for Wisdom of the Ancients thanks to XKCD

Wednesday, 28 December 2016

BT and their wifi adverts

BT have made some interesting claims regarding their WiFi, with the latest being that it is the "most powerful".

Now this is a rather odd claim as "power" is not something that is all that relevant - power (measured in Watts) is not that helpful as a measure of WiFi, indeed many smaller APs with lower power can (I believe) provide a better coverage and performance. Saying you have the most powerful WiFi is like saying your house has the brightest street light outside it. The main impact being it will make other WiFi nearby worse.

BT have made all sorts of claims before, all of them (in my view) rather suspect. The claim of most powerful WiFi, when WiFi is a radio data system to strict international and national agreed standards, is rather odd. The WiFi will have the power within the standard and legislation, like any other WiFi. It cannot in practice be more powerful.

They even published a document to justify the claim (here).

First issue: "The BT Smart Hub has superior specifications than the routers of all major broadband providers". So only most "powerful" if you ignore the smaller providers. They only look at "major" providers. AAISP have been offering Unifi APs and packs of multiple Unifi APs for some years now, but that does not count as not a "major" provider.

Second issue: The comparison compared many things but not one of them was in fact "power"! They state: "The most important aspect of wi-fi for customers is their Transmission Control Protocol (TCP) throughput.". Whilst this is actually a quite good metric, it has absolutely nothing to do with the claim of being most powerful. Power is in Watts and is not a measurement of download speed.

Third issue: They actually tested the WiFi. This is good as that is what they are claiming is most powerful, but they are selling an "Internet Access Service" using this. The tests are nothing to do with Internet access (you can tell from the speeds they measured) and for most people any speed on the WiFi that is over the speed of their Internet Access is irrelevant, so no help. Yet the advert is to sell Internet Access, not simply WiFi APs.

Basically, they are simply claiming they have a good 3x3 antennae single AP WiFi system they sell/provide with the Internet access system they sell and that it is somehow more "powerful" than other ISPs. They ignore the other (smaller) ISPs selling systems just as good. They ignore those selling multiple access point solutions which are better. They ignore all of the non ISPs also selling this equipment. And they ignore that the actual "power" is the same on these devices and their claim of most "powerful" is not actually about "power" at all but TCP throughput.

Anyway, yes, consumers want an Internet access service that is good. If BT are "most powerful" in that, why are many ISPs (including AAISP) way higher in ispreview's list? (here)

Thursday, 22 December 2016

Connecting to @AAISP Fast?

Over the last week or so we have had a lot of custumers that were with "Fast" wanting to sign up with us urgently because they, rather unceremoniously, dropped all broadband customers overnight!

The good news is that most of their customers are using a back-haul provider we use, and that means that using our login on their existing line "just works".

There may be exceptions, but we have connected loads of ex-Fast customers same day, once they order we allocate a username and password and allow them in. Some are on-line within minutes.

We had to tweak the systems we have to allow this. Normally people can only log in once installed. But with some complicated work on the RADIUS server, we managed it.

Once the day comes to actually migrate there may be some downtime - some re-jumpering, etc. But overall this is a bonus for all those stranded customers. Getting on-line before Christmas matters.

It did rather put a strain on the staff just before Christmas, and even managed to upset my system for attack management that thought someone was pushing automated invalid orders at us! Soon sorted.

But, as ever, we'll aim to offer an excellent service to those customers moving to us, and ensure it all works over the holiday period.

Merry Christmas to all our new customers.

Director of A&A

Wednesday, 21 December 2016

Good news for privacy - Investigatory Powers Act vs CJEU

As reported by the BBC, the European Court of Justice has made a ruling that could seriously impact the powers in the Investigatory Powers Act to collect data on everyone in the UK.

The IP Act has provisions, much like the Data Retention and Investigatory Powers Act (DRIPA) it replaces, and the Data Retention Directive (DRD) before it, to retain data about use of communications systems.

The IP Act actually pushes this much further - previously telcos/ISPs could have been asked to retain certain data they processed (e.g. telephone itemised billing records) but could not be required to actually generate data they were not processing. The IP Act allows much more and it has been made clear that the government wish to log usage of the Internet in some detail - down to the level of recording every web site everyone has accessed. This is far more than just retention of data, and would apply to everyone, even those not suspected of any crime.

The good news is that the ruling from the CJEU is that this sort of mass retention of data is not consistent with our basic human rights and EU law. These apply regardless of whether we leave the EU or not.

The BBC article is not ideal in its analysis, and Open Rights Group have a much better analysis (here).

Retention is an invasion of privacy

The key point of argument here is that the UK Government considered that indiscriminate retaining of data should be allowed as long as access to that data was restricted and controlled in a suitable way. However, that is not the case. The court ruled that indiscriminate retaining of data was simply not acceptable. You have to be much more specific about whose data is to be collected to target suspects in a crime.

Only to be used for serious crime

The court also looked at the issue of controls over access to the retained data. Again, this did not go well as the access has to be restricted to only serious crime. The IP Act tries to even redefine serious crime to include things that are not serious, so that will have to change too.

Proper independent authorisation of requests for data

On top of that - the access to the retained data should be approved by an independent body, such as a court, and not simply by the current system of a Designated Senior Officer. This could finally mean we see proper court warrants for access to retained data.

No more secrecy

As I have long said, the secrecy around data retention and collection of data is not really acceptable. The ruling says subjects of access should be told about it once there is no longer a risk of prejudice to the investigation.

We can still catch criminals

None of this stops wire taps (or the Internet equivalent) on suspects in serious crime, set up and accessed with the proper controls. All it stops is the indiscriminate logging of everything we all do on the Internet - and that is a good thing - we are all meant to be innocent until proven guilty, after all.

Read more

Read the ORG article for a lot more useful insight in to this ruling.

Tuesday, 20 December 2016

IEC18004 QR Codes

I said I had my mojo back :-) Yesterday afternoon I decided to have a bash at writing a QR code encoding library, from scratch.

Yes, this is re-inventing the wheel as there are QR encoding libraries out there. It was fun, and it is always nice to have source code that is ours, especially if we may put it in the FireBrick (I am looking at making the TOTP logic in the FireBrick a lot easier to use).

Thankfully Cliff had already written a Reed/Soloman ECC generation function for me, and has made me a very simple BCH coding function. Whilst I understand Error Correction Code, it really is just beyond me in terms of the maths.

I found a copy of IEC18004 on-line. You normally have to pay for a spec, and I may do so at some point, but the court ruling on reading stuff on-line using your browser makes clear that I am not breaking copyright simply be reading it in my browser - whoever is hosting it is. It is 118 pages long!

What really annoys me about this whole specification is the tables of numbers. Instead of saying that the alignment marks will be evenly spaced with spacing between 16 and 20 units starting on unit 6, or something like that, they have a table that states the positioning for each. I played around and worked out a simple algorithm to work out the table and so did not have to use the table - yay. I double checked my calculations only to find one barcode size does not follow the same logic and is a special case for no apparent reason. Why not just make it a simple algorithm?

You then have the same for the level of ECC coding - rather than say "medium ECC uses X% of the space for ECC words" and work that out for each size, there is a table, for four different ECC levels for 40 different sizes of barcode. Then the number of blocks used for ECC is not something simple like "use more blocks when data encoding size is 32 bytes or more" or something simple, no, again a table, for all four ECC levels and all 40 sizes. It drives me round the bend. It could be one line of C rather than typing and double checking and testing hundreds of numbers in to a table.

Anyway, in the end, I have myself a nice little library that codes in 8 bit, Alphanumeric, or Numeric (not Kanji, but I could add that I guess). It codes the input all in one format only - I may, later, make something to work out optimal coding of the string changing coding in the middle as needed, like I did for the IEC16022 barcode library I wrote years ago, but I suspect there is no point.

It is very useful having QR readers on my phone to test it, and the reference coding in the specification was really useful too. I like specs that do a worked example like that.

All in all a fun little project for a Monday afternoon.

P.S. I have added my library to the free A&A code page

Sunday, 18 December 2016

Boiling a frog, and old age

We know the story of boiling a frog - you start with cold water and gradually make it warmer, that way the frog does not notice and jump out. [who would do that?!]

Well, I have noticed that getting old is like that. Several times now I have discovered a change in my life that only strikes me when fixed. Being diagnosed diabetic was scary as only when I was on medication did I realise how much all the symptoms crept up on me over the year before. These are symptoms I knew to look for and had drummed in to me by my mother since I was a child, and still they eluded me. Mostly tired and thirsty. I had got used to taking a glass of water to bed - which stopped being necessary as soon as I was on medication. Now I am on insulin, and my diabetes is well under control, or so I thought. Indeed, the annual reviews and HbA1c tests are all good.

The latest example is one where, over time, I have realised that whilst generally feeling reasonably heathy, I was going to bed tired sooner, and feeling much more apathetic and doing less work. If I was up at 9pm there was a joke in my family that it was past my bed time. That should have been a clue. I would sleep for like 9 hours a night, and not do a lot of work during the day.

Then I was put on indapamide as my blood pressure was getting higher, as I blogged recently. The 2.5mg dose was too high and I felt like crap, but now on 1.25mg, I feel better. I realise that since I started on the indapamide I am feeling "better". Over the last few weeks I have designed, coded, and deployed the whole 2FA systems for A&A (four separate systems), whilst also coding a load of other stuff including a Monzo API library and a few other things - documenting it all, and testing it all.

To my surprise, I look back at last week, and realise a couple of days ago I was up at 5:30 am and working solidly until 11:30 at night with no problem, only to be up at 6:30 the next day. I am finding I am bored just watching TV or going to bed, and instead am doing stuff. All last night I was designing in my head new code for a feature on the FireBrick which I ended up getting up and documenting first thing this morning. I feel like I have my mojo back.

The issue is not, as I see it, the blood pressure, which is what the indapamide is for, but it has changed the way my diabetes is working - I am having to take more insulin, about twice what I was, but I am much more stable now. It will be interesting to see my HbA1c in a few weeks time. Indapamide is not listed as a treatment in any way for diabetes, just that it can impact blood glucose levels. What is encouraging is that, having mentioned on a recent blog, I am not alone. Others with diabetes found they were "revived" (which I feel is a really good description) once on indapamide. So maybe it should be a diabetes related treatment?

Now I wonder what the next thing will be - something that will creep up on me over many months before I realise.

Friday, 16 December 2016

Change Freeze

Tricky subject, and the very fact the subject has come up means something for the size of A&A now.

We have a change freeze, started this afternoon, and going on until after new year bank holiday.

The principle is fine - we have a lot of staff off, especially some of the senior technical staff, and none of us want major issues whilst we are at home with family if it can be avoided.

So the idea is we don't make major changes or deploy new systems over the change freeze. Nice idea.

There are, however, a few problems, and it is a change for the way I work for a start.

I am very keen to do a job and finish and deploy it - I hate having any job interrupted by a big gap - I lose track of what I am doing and spend a lot of time catching up and things can be missed. So this means that where there is a job in progress before xmas, I have been rushing to make sure it is all deployed before the change freeze. This is not to say taking short cuts as such, but rushing. I don't want a half finished job not deployed. And no, finishing on a dev system and deploying next year is not good - I like to deploy things as I go and pick up issues and fix them whilst still fresh in my mind. If I did the work and did not deploy for two weeks that would be horrid.

We also have the fact that xmas can be a quiet period from a technical point of view - it is (was) an ideal time to deploy and test changes with lower than usual impact. For a start, a whole bunch of customers are not even there - businesses shutting down. And whilst I don't mean to say business customers are more important than residential, there is a difference for a business customer disrupted in their business for a few minutes, or a home customer disrupted whilst eating mince pies. So traditionally the xmas break has been a good time to work on some major projects and iron out the bugs before everyone is back to work or doing anything serious with what we sell.

Ironically, whilst a few months ago, I would almost be happy to sit around doing nothing all xmas break, we now finally have me on medication for my blood pressure which has had some sort of impact on my diabetes which means for last few weeks I feel much more like I was in my 20's, bored of watching TV, and coding from dawn to dusk (well much later with it being winter). Seriously, this is great, even if it won't last (5mg perindopril + 1.25mg indapamide, FTW).

We had only one snag with stuff rushed through yesterday, and it was not actually due to rushing at all, it was a VoIP issue, which is a complicated set of issues where a recent change, which had been tested on several boxes, was deployed as part of an urgent update to address a customer issue. Sadly, when load got to a certain magic level on the live VoIP servers we go drop outs. Our normal testing on several other boxes did not pick it up, and would not have had we not had the change freeze and hence done the update next week instead. Sorry for the inconvenience on that - the VoIP servers are a pain as reloading means dropping calls but waiting means people with dropouts in calls until we do - we managed to move calls and so only drop a few to get the new code deployed during the afternoon.

But overall I feel rushed by the change freeze and not entirely convinced it will help with issues cropping up or not. I guess we'll see over next couple of weeks, if I go crazy, and/or make a huge list of changes all done on Jan 3rd and consequences of that.

If I do have my mojo back, I am damn well going to do stuff, but maybe not A&A stuff. My son has a load of web/app sites that could be tidied up, and my mate Mike has loads of stuff he wants re-inventing from scratch (probably including "the wheel", knowing him). I may find stuff to do.

So, happy freeze everyone.

How not to do 2FA?

We have purchasing cards with Barclays and the statements come in on a web portal.

The site has a secondary question, which I think they pick from various questions that were asked when originally set up.

So, I logged in, and was asked the extra security question, and got it wrong. The problem is that it was "What is your mother's middle name?". This is a horrid question! (a) not everyone has a middle name, and (b) she has two of them. So I forgot what I had put originally and got it wrong.

So, locked out. Great.

I have spent literally a month trying to get it sorted, with email replies taking a week, and eventually a lot of phoning and getting our business relationship manager to chase, finally, the login was reactivated. Not a good user experience at all.

Same question, same mistake, locked out again, arrrrg!

OK, one more time with the shouting and chasing, and what do I get.


Yes, an unsigned, unencrypted, plain text email with a plain text password quoted that is valid for 2 months! (Yes, I have changed it).

Anyway, this time I guessed the right answer to the question.

To be fair, a password reset process is tricky, we send a link valid for a few hours, but that too is as good as plain text in a way as someone could use it. Just seems so very wrong sending a plain text password by email somehow. I am glad we are setting up the proper 2FA stuff on our systems.

Even so, this looked so much like some sort of spam I nearly deleted it.

OFCOM Broadband USO

Arrrrg! This is a knee jerk reaction - I'll do a proper response to them shortly.

OFCOM published guidance to Government on technical specification for the Universal Service Obligation for broadband. Here (PDF).

In it they have three scenarios:-
  1. a standard broadband service, characterised only by a 10Mbit/s download speed; 
  2. a more highly specified standard broadband service, adding upload speed (1Mbit/s), latency (medium response time), maximum sharing between customers (a ‘contention ratio’ of 50:1), and a defined data cap based on current usage profiles (100GB per month); and 
  3. a superfast broadband service, with download speeds of 30Mbit/s, upload of 6Mbit/s, fast response times, a ‘committed information rate’ of 10Mbit/s (i.e. guaranteed 10Mbit/s at all times) and an unlimited usage cap.
Now, I am pleased there is mention of latency, but no mention of the latency being when idle (i.e. not when a queue on the customers own router adds latency), and no mention of packet loss when idle. They also don't define where latency is measured.

But again, they talk of "speed" and "contention" and even "committed" rates.


Speed (of what?, and to where?)

So, let's start with speed. In the industry and since the days of modems, this has always been the modem link speed (or radio link, etc). It is the raw speed of the link (and usually before overheads like ATM, but that is just a matter of percentage adjustments). It is the speed from the modem at the customer premises to or from the modem at the other end of a wire or radio link.

This speed is important as it was usually the key factor in the user experience - but times have changed. These days users may find that they have an 80Mb/s VDSL sync, but cannot download some film or game at more than a few Mb/s. This could be down to congestion from cabinet to exchange, from exchange to BRAS, from BRAS to ISP, from ISP to internet, within the internet backhaul, or at the serving end. Only some of these factors are within the ISPs control, and some are within the back-haul carriers control. Often you find you cannot fill your 80Mb/s because of other factors. So are OFCOM actually only talking of sync speed still?

They do mention speed as between ISP access network and premises. But this is not a lot of help, as one could have the "ISP access network" in the exchange and/or contention within the ISP. If they are talking of Openreach here, it would be to the exchange only. They ignore congestion in the Internet back-haul or at the serving end of communications. They also talk of it varying depending on contention in the network when actually the issue is congestion. They also talk of it varying depending on home wiring - but that is not between the ISP and consumer premises - but within the premises and not ISPs job!

Committed speed?

This is special. The back-haul providers may offer committed speeds in parts of their network, and will charge a lot for it. In practice it is simply not needed as both BT and TT back-haul are generally not congested. But you, once again, have to ask where this 10Mb/s is committed too?

On the modem to modem link, if the sync is over 10Mb/s then you have a committed speed of that sync all the way to the other end of the wire where the other modem is, simple. Does that meet the requirements, or does this commitment have to go further?

What of to the ISP? Well, as an ISP we have lots of people on what we would call "super fast" links. But we do not buy 10Mb/s times the number of such lines. We buy capacity to avoid being the bottle neck (and we are better than many ISPs in that respect). Where the average download of customers at peak time is around 0.5Mb/s then obviously the capacity we buy is of the order of 0.5Mb/s * number of lines and a bit of headroom. Buying 20 times that will not make anybody's downloads any faster, it just means we charge 20 times as much to cover extra costs (well, not quite, but a lot of the price is the back-haul bandwidth). It makes no financial sense for an ISP to dedicate 10Mb/s on a service where the usage is way less, even if a back-haul provider would offer that as a service. And the back-haul providers have the same model - to get a dedicated 10Mb/s would be stupidly expensive. I may price it up on BT in my reply to OFCOM. But it is silly - why have a service offering that needless costs 20 times what is needed to offer no extra performance and just the nice feeling of links at only 5% utilisation?!

But what then - this dedicated 10Mb/s gets to the ISP. Maybe the ISP even buys transit and peering links to accommodate that, what then. That adds again to the expense - meaning even a small ISP like us would need many 10Gb/s external links - around 20 times what we need for customer traffic.

Well, then there is the Internet. Let's say there is a web site on the Internet. Let's say that server has a 1Gb/s link to the Internet. Let's say we look at UK only, and there are what, 4 million people in UK that can get super fast broadband? If they all have 10Mb/s dedicated, that one web site needs a 40Tb/s link to the Internet to ensure all of the UK super fast users have a dedicated 10Mb/s to that one server...

But that is crazy, clearly. This is not a USO on web sites is it? Well if not, then what is the metric for? Where does that 10Mb/s have to go. End users are buying internet access, so anything short of 10Mb/s dedicated to their favourite website is not actually 10Mb/s dedicated, is it? Is 10Mb/s dedicated to their street cabinet acceptable? This is going to cause customer confusion.


Contention is no longer a sensible measure, and even when it was, it only make sense if you specific the two points where the contention is measured.

Specifying 50:1 makes no sense. For a start, it is massively different if you have 50:1 or 5000:100. If you have 10Mb/s and there are 49 others sharing a 10Mb/s link, then two people downloading at once get 5Mb/s each and see "slow" Internet. If there are 5000 people sharing a Gb/s link, then you need 100 other people downloading at 10Mb/s to slow your link 1%, so access seems much faster.

In practice, what matters is a capacity for each end user that reflects normal end user access rates at peak times, e.g. 500kb/s (as it seems now). That means you normally have uncontested links. That measure needs to change over time. You need links at least a number of times the size of the end user min size, so if 10Mb/s is min, then links that are 1Gb/s. Specifying contention is not the way to do it.

But also, where is that contention measured. Once again, modem to modem is 1:1 and not shared. Cabinet to exchange will have some contention, but if not congested the contention does not matter. Contention in backhaul and back to ISP is another factor.

Also, with line speeds going up so much - contention is more problematic. If a line is 80Mb/s at 50:1 then that means an average capacity per user of 1.6Mb/s per user, when in fact all you need us around 0.5Mb/s. But if users are 10Mb/s you only need 0.2Mb/s per user, which is poor these days in the netflix generation.

We still come back to this being an Internet service and so that web server with 1G/s link, and accessible by a billion people around the world, what is that contention ratio?

They also talk of contention "at a node" but do not say at what node, or why they have picked that node rather than any of the other points elsewhere between some Facebook server and the end users laptop. Again, user confusion.


It does look like they are talking just access network broadband and maybe back-haul here, but I do not think the document makes that at all clear. I assume they hope if good access networks exists then Internet access will simply follow and not be an issue. That may be true in some aspects, but ISP models depend on the pricing of the back-haul, and that is expensive, so some ISP models involve congestion at the ISP. That model is not helped by this USO at all.

I am not sure they are addressing user confusion on this at all - even someone paying (at lot) for 10Mb/s committed rate cannot expect to download 10Mb/s from their favourite web site, but they probably will expect that from the ISP somehow if that is what they are paying for.

Bear in mind, one of the providers here is Openreach, and they only operate from master socket to the exchange. So do they meet a USO if the speed to/from the exchange meets this spec? What of BTW/TT back-haul? To be fair, that is usually fine, but won't meet defined contention or committed speeds without stupidly big links from them to the ISP being mandated somehow.

It needs work!

Thursday, 15 December 2016

What we did in the end for A&A 2FA

The system is OATH/TOTP 6 digit 30 second authenticator codes, set up by QR code. We have TRNGs we use for seeds that are 320 bits long.

On the accounts system we have gone for some flexibility. Option to SMS codes instead, but configurable, and configurable trust level to decide when to ask for a code. It is also a seed we hold so staff can ask for a code to check you are who you say you are (a useful feature on phone, irc, web chart, etc).

On the control pages (and the internal staff A&A systems) we have gone for encrypted TOTP seed and no SMS option. The seed is binary data, XOR'd with a stretched Argon2 hash of the password and a seed set for that purpose (i.e. the seed also has a random seed for its encryption), so no way to check you have right answer other than doing the Argon2 hash and checking an authenticator code, so not a shortcut to crack the password hash.

This means that on control pages the password change needs old password if you have 2FA set up, and expects an authenticator code as well. Some staff can override, but they will also look at account settings as part of deciding you are you!

I think, overall, we are doing well. Hashed passwords and 2FA with encrypted 2FA seeds.

There is always more to do, and more security to add, but this is an ongoing process.

Customers can now set up 2FA on A&A accounts and control pages if they wish - have fun.

Tuesday, 13 December 2016

Copyright and links

One of the rather annoying and weird bits of copyright legislation is that it does not just protect against copying but also making available. The second part is the tricky one, and a CJEU ruling recently muddied the waters only to be made worse by a case in Germany!

More on this from arstechnica.

The upshot is that if a commercial web site simply links to a web site/page that contains infringing material then the linking site becomes infringing as it is making available.

What is worse is that the link itself (according the Germans) does not have to be for some profitable purpose, simply a link on an otherwise commercial site. Also, the web site operator that created the link does not even have to know the linked-to site is infringing. Indeed, they could have done all due diligence when making the link and the content of the target site has since changed, or worse, not changed but the infringement status of what is there has (a time limited licence on use of an image, maybe). The German case was a link to something covered by a creative commons licence but it turns out the linked to site did not meet all of the requirements making it an infringing site. How the hell does someone making a link check that shit, and how can web sites continue to exist if every external link on every web page needs a small team of lawyers to check it, and recheck regularly?

This is, of course, crazy, and make no sense to anyone looking at it in any technical way. It makes little sense to those looking at it from a legal viewpoint either, as far as I know.

One of the problems is that the linking site being infringing means that anyone linking to the linking site is also infringing, and so on until the whole world wide web is infringing! If it was not like that, then you do not tackle the original problem - people actually linking to where one can download dodgy copies of stuff can simply link instead to a site that then links to where you can download dodgy copies of stuff, ideally with that intermediate site being outside of EU (and this crazy legislation).

Of course, you could make a non profit site that links on to other sites, like a URL shorter, but could be simpler and just strip its domain off end of link so very noddy. Then make all external links on your site go to that non profit site that links on to the target page. That way all your links are now laundered and not infringing?

I am not sure how either of these play points out legally.

Monday, 12 December 2016

The TOTP seed storage dilemma

When making any sort of login system you typically used a username and password. One of the key things you should do, if at all possible, is hash the password.

This means that we do not know the password people have used! We can check a password attempt against the hash (and then forget the password), but we never store the actual password.

If the user database was to be compromised in any way the attackers would not get real passwords, and so could not use them. More importantly, given so many people re-use passwords, it does not give then the passwords people are using on other systems.

So far, so good.

In additional to passwords we are now using two factor authentication using an authenticator app that provides a new 6 digit code every 30 seconds (Timed One Time Passwords). This uses a seed that is a long random number which is stored in the app and which we have to know as well - that way we can generate the same code and check it matches. We actually generate the codes for the last few minutes and check it matches any of them.

This creates two factors - one is something you know, being the username and password, and the other is something you have being the smartphone app or authenticator device. There are, of course, issues of ensuring the two have the same seed, but using a QR code on an https page seems a good compromise.

The problem is that we have to be able to see the seed to check the code, so it is not hidden. If that seed gets out then the authenticator is compromised as someone else can always generate the same codes. So in an ideal world we do not want to be storing this seed in the clear.

The small revelation I had this morning was that we could simply encrypt the seed with the plain text password. This means that when you provide the passwords and authenticator code, we can check the password, and knowing it is right we can use it to decrypt the seed and check the code, all in one go.

This is great, and I nearly rushed off an implemented it before realising a significant number of shortcomings with this.

One big problem is lost passwords. When changing password you always have to know old and new passwords so as to decrypt the seed with the old one and re-encrypt with the new one. This is fine for a change password form, but not for any sort of lost password reset process.

Indeed, at present, we use the authenticator code to validate the reset password request that is sent by email (so working email as well as using the authenticator code as two factors). However, if the authenticator code cannot be validated without the password, you cannot do that. You either have to trust just the email working, which is not ideal, or you have to find some other validation process as well. Also, when resetting a password you have no choice but to also issue a new authenticator seed and reset up the app with that new seed.

You also cannot use the code as a validator when talking to staff as they could only check the code unless they also have the password, and we would never want to ask a customer for their password.

So this creates a trade off - transparent storage of the seed on our systems and added convenience and some extra security on password reset, or encrypted seed on our system and some much more constrained processes and less convenience.

I can see we may end up with the underlying libraries allowing both options and using for different systems as appropriate.

Isn't security fun some times :-)

P.S. Read the comments - at least one important point I had not realised.

Saturday, 10 December 2016

Leaning to code

I have to say I am slightly impressed and pleased with my son's abilities in coding today.

He has been working on tools to have transaction details from Monzo, specifically to handle money loaned and repaid. I have written a load of C code behind the scenes for him to get the transaction data and run a script of his.

The fact Monzo have an API is great for this, and the real-time nature of the web hooks is even better. They lack an "update" web hook, but all in all it is pretty impressive.

Now, what struck me as insightful is a couple of questions James asked, and importantly he asked before he hit the problem caused by them!!!

1. He realised that if he happens to be set up to track Monzo accounts for both sides (him and his girlfriend), he will see the same transaction twice, and hence record the transaction twice, once from each side. But there are scenarios where he is not tracking both sides and so only sees it once. He needs to de-dup the transactions. I am impressed he realised this, and he has managed to find a reference in the transaction which is the same on both sides (a p2p transaction id). So he can de-dup that. He even worked out that matching by amount and parties and time is a really bad idea to de-dup this stuff.

2. He also realised that he might get the two sides of a transaction concurrently and so code that checks for it existing, and if it does not, goes on to add the transaction, could happen concurrently and add both. This can be solved in many ways from locking around the transaction handling script, to table locks in SQL, to unique keys on tables. But the fact he worked out it was a risk is excellent. So many people do not understand "real time" coding and race conditions, and he spotted this as an issue, and once again did so before it happened.

So, well done, my mini-me is growing up.

Thursday, 8 December 2016

2FA on A&A control pages

I think we have 2FA sorted nicely on our accounts pages for A&A.

We have taken on board some constructive comments, and done things like "you can't set paranoid mode until you have confirmed that the app has been installed and used a code", and also not showing the QR code or seed again, once installed.

The trick to both of these was to use a different seed for codes sent by SMS than codes from the authenticator - that way we can tell if the authenticator has in fact been used and not just an SMS'd code. Obviously we did have to allow for the remote chance of code matching both seeds and ask for a new code in such cases.

I event made a video showing how to set it up!

The next step is 2FA on our control pages. But first it is worth explaining - yes, I know that really what you should do is identify a specific living individual in some way, and separately have associations of accounts or logins that they are allowed to access in various ways. The system we have does not do that, I know - we have the accounts logins and the control pages logins. The system we have also has a complex set of linkages such as dealer logins on control pages, and, of course, staff logins. Changing to a "single sign on" is a good idea, but a big step we'll tackle another day.

The plan is to use the same library and tools, and almost identical set up processes, as the accounts 2FA system. Indeed, some of the pages/scripts will simply be copied and amended for the different database structures in use on the control pages.

There is, however, one extra trick we can do, and it will be an extra button. As we have the "seed" for the 2FA on the accounts, we can simply have an option to "Copy 2FA from account" for an associated control pages login - why not? Obviously we will ask for password and a new code at the time to confirm you have the authenticator, and there is no reason to show a QR code when doing this. But this would reduce the number of authenticator entries you need installed and will be ideal for cases where it is one person handling accounts and technical issues - like most of our home customers.

This would just be an option though - customers can have separate control for accounts and technical, and have separate people and hence separate authenticators for the control pages if they want.

I hope that sounds sensible. However, I do plan to "let the dust settle" a bit, and see how the accounts 2FA works out before working on the 2FA on the control pages. Feedback welcome, as always.

Tuesday, 6 December 2016

Security is a battle on two fronts

As an ISP, A&A are obviously quite concerned with security. Many ISPs have had leaks, and we hope never to be among them.

But "security" is far from being an absolute. It is a battleground, and whilst some part of that is the general battle for privacy and the stupidity of UK law, the main battles we face fall in to two areas...

1. The bad guys
2. The users

New hashing algorithm

The battle with the bad guys is hard and never ending. Every step you take is a mitigating factor. We have a dedicated ops team and part of their remit is security so they are constantly finding things we should improve to be best practice, or more often beyond best practice, if we can.

Some time ago we instigated a password hashing improvement programme. At the time, the password hash competition was not complete so we went for a heavily salted SHA256 hash. However, the main change at the time was not choice of hash but choice of a system of automatic upgrade. All of the systems we use, where possible, not only use the latest preferred hash but update the hash we have when someone next successfully logs in.

This meant that at the time our accounts and control pages and several internal systems moved to that SHA256 hash very quickly. However, we know that SHA256 was not the best approach as it is a cryptographic hash and not a password hash. There are different types of hash that have different objectives, and a password hash is designed to be time and memory consuming where as a cryptographic hash is designed to be quick but impossible (for some values of impossible) to reverse.

So, having put this all in place some time ago, we recently moved the the competition winner, Argon2. This is a specifically designed password hash, so any successful login will move your hash to this.

Why is this important? Well, it relates to the risk that our database is ever compromised. Obviously we work hard to avoid that, but if it happens then the hashes will not easily be crackable to find passwords. That is the plan. Not all systems allow passwords to be held as a hash, but our various web site logons do.

But tackling the bad guys is not all technology - it is also the social engineering. The call we get at 10 past 5 from someone that is as nice as pie and visiting his parents house for his fathers funeral and does not have the details and just needs this minor change done over the phone. The bad guys are good at this shit, and we have to be vigilant but somehow also allow for the customer that in genuinely in that situation!

But that leads me on to the other battle - that with the users (aka customers).

Bear in mind some ISPs store such passwords in plain text and show to support staff!

Battling customers?

OK that sounds unfair, we should never be battling our customers, but the real battle is human behaviour. People will re-use passwords or use dumb passwords. This is why our password setting system is hard to not accept the pre-set random one we offer. We don't quite make it impossible to pick your own password, because we know of people that do run password apps that provide individual and very secure passwords to use on our system. Sadly, ultimately, we cannot tell such people from those that want to re-use a password or set to "PA55W0RD".

But even then the battle is more subtle - people will store passwords in their browser and then get hacked and passwords collected. People are inherently lazy, and we all know it. We are all the same.

So, our latest initiative is allowing two factor authentication on our accounts system web login. This is an extra step that is not possible (in theory) to store in the browser - a code that changes every 30 seconds from an app or device you have, usually a mobile phone app.

But as part of that we need to also allow people to have trusted browsers that stay logged in, or trusted browsers that do not ask for the code (usually). If we ask for the code every time people will turn off the feature. Remember, people are lazy. Security is always a compromise with convenience.

So we ended up allowing a paranoia setting. Customers can, if they wish, set so the code is needed every time, and even staff will not talk about the account unless you can quote the code over the phone (or irc, or web chat or whatever). But people can set less severe modes where the code is needed on login only if not your usual machine or a recent bad password entry.

We have decided that if you have set up 2FA then we do insist on the code on all orders, even if over the phone. But ordering is rare enough that people can cope with that, we think. The whole 2FA remains optional.

We think we have the right balance of convenience and security now on the accounts web site. Next step is our to our "control" pages. But behind the scenes we are working on more more systems to improve security all of the time.

Monday, 5 December 2016

Investigatory Powers Act - devil in the detail

It is published (here). It is an interesting read, so here are some initial observations...

I have been trying to focus on the bits that could impact us (A&A and FireBrick) mainly, and I am very happy to have had help from a friendly lawyer on this matter. I am the first to accept that I am not an expert on reading legislation, but getting better as the years go on.

So, some observations, in no particular order...

Can a retention order be placed on BT Wholesale to monitor A&A traffic?

We think no - surprisingly. This is because of 87(4): "A retention notice must not require an operator who controls or provides a telecommunication system (“the system operator”) to retain data which relates to the use of a telecommunications service provided by another telecommunications operator in relation to that system".

So that should mean, we think, that BT Wholesale or Openreach or BT plc as "the system operator" cannot be ordered to retain data which relates to the use of the telecommunications service provided by A&A in relation to that system. We see that as meaning BT provide PPP and we provide IP, and so BT cannot be ordered to log IP (or above), only PPP which is basically their RADIUS logs, because IP is related to what we provide via that system.

Good and bad - good is it means, in theory, if we say we have no monitoring (we don't) and we can assume BT do not, then there is no monitoring (same logic to LINX and transit providers). Bad news is that they may be more inclined to ask us to do retention as a niche ISP.

But it gets more fun - given that this now covers private as well as public telecommunications services, it is easy to say that every single one of our customers is a telecommunications operator even if only running one router to provide service to one person. So we can argue that we cannot be expected to retain data relating to our customer's use of the IP - you have to ask each and every one of them to retain data and not us.

We'll see how that plays out if ever we are asked to do retention (which we, A&A, have not been).

Can FireBrick be forced to add a back door?

We think no, thankfully. The definition of a telecommunications operator, which we thought could cover FireBrick would require that FireBrick is providing a "service", which we are not, we are providing a product, and that the FireBrick itself is a "system", which it is not, it is apparatus.

Even so, we still have standing order that if asked to back-door FireBricks then the UK company FireBrick Ltd would be dissolved.

In short, you can trust FireBrick!

Is FaceBook a telecommunications operator?

Well, this is tricky. Home office think so, apparently. An operator offers "services", and services means a service consisting of access to or facilitating making use of, a "system". A system is something allowing transmission of communications by electrical or electromagnetic energy.

So a system is wires and fibres and radio; A services provides access to that or making use of that; An operator offers a service to do that.

I think the wires, and fibres, and radio, facilitate the use of FaceBook, not the other way around. The "make use of" may be the sticking point.

I think it is badly drafted! FaceBook may want to argue on that definition.

What are Internet Connection Records?

Something much hyped in the process of this becoming law, but relegated to a small part of the Act.

It is a narrow and specific definition, "In this Act “internet connection record” means communications data which may be used to identify, or assist in identifying, a telecommunications service to which a communication is transmitted by means of a telecommunication system for the purpose of obtaining access to, or running, a computer file or computer program, and comprises data generated or processed by a telecommunications operator in the process of supplying the telecommunications service to the sender of the communication (whether or not a person)."

So it is just stuff to identify the service used by the sender, nothing more. But why does this narrow definition matter?

Well, retention can cover all sorts of data, anything that is not "content", which is "meaning of the communication". And that can be way more than ICRs. It is clear that ICRs are a subset of that data.

However, requests for this data to be acquired (e.g. from retained data) can cover anything.

There are restrictions on "local authorities" getting ICRs, but as that is a subset of the data ISPs may be forced to collect. So that is a less than useful constraint. Local authorities could ask for all sorts of non ICR data an ISP was required to "retain"!

How serious is "serious crime"?

Some aspects of the acquisition of data have restrictions for "serious crime", and that covers stuff with long prison sentences. Good. But, oddly the section also covers "relevant crime" which is rather fun as it covers offences that are "by a person who is not an individual, or which involves, as an integral part of it, the sending of a communication or a breach of a person’s privacy." This means things like failing to put your company number on your letterhead (a crime by a company) is lumped in with "serious crime"!

And the irony that you can get all this data which is a huge invasion of privacy to investigate a breach of a person's privacy is not lost on me.

Can the food standards agency get browsing history?

Well there are caveats, but yes, they are in the list and not even covered by the "local authority" exception to getting ICRs.

Does this mean back-doors can be mandated?

Well, yes, to any "service" which can be ordered to maintain a capability to decrypt stuff and even notify if new services are planned to ensure they have the back-door.

But not if you do the encryption yourself, using PGP or your own apps or pen and paper! Criminals can do this and do so legally with no interference by this Act. Well done!

Friday, 2 December 2016

Two factor authentication

I am working on some new two factor authentication for our systems.

Before I even started this, I actually updated the systems we have in place for managing password hashes to move to the password competition winner Argon2. It updates the hash on next login to our various systems.

However, a big step forward would be two factor authentication where in addition to a username and a password we ask for an extra bit of information.

From various research the way to do this is using TOTP (which is a timed OTP using OATH hashing system). Basically you have an app or device that provides a code every so often, and when you log in you have to enter the current code. We are using the default of 6 digit codes created ever 30 seconds.

There are quite a few issues with this, and a scarily large number of OTP and OATH and TOTP applications available. It is a well published standard.

The challenge is getting the "seed" or "key" in to the device, or if it is a hardware device, then from the device to us. The latter is something to tackle later as most people use a mobile app these days, so we make the seed/key and it has to get in to the app.

The answer is a QR coded URI and there is a "standard" for this. It encodes the settings in a standard format with the seed/key in BASE32 which can be read by various apps including Google Authenticator. Once read, it provides a code every 30 seconds.

At our end we need to store the seed, which ultimately has to be readable. But we have hash for password and a readable OTP seed, so two factors, which is a good start. There is no real way around storing the seed in a readable format, sadly.

But it does get quite complex, and this is what I am working through now.

1. How do you make sure setting up or resetting the TOTP is safe / authenticated. Current plan is texting a code as an alternative two factor authentication before we can disclose the seed/key as a QR code. Some actions need to be properly two factor authenticated.

2. Do we allow changes of password if not already TFA, and what of lost password - is that independent?

3. What access do staff have to reset or clear the TFA system? How do we defend against social engineering whilst not locking out genuine customers? How much staff training on social engineering can we do? Ho much staff time will this take?

4. What levels of control do we offer to customers, what degrees of paranoia do we support?

5. What of ancillary systems such as ordering or the CHAOS2 API? Current plan is ordering will require the TOTP code if that is set up at all, even if normal logins not requiring as "trusted browser".

It is never as simple as it sounds when looking purely at the technical side. Systems like this extend in to social engineering!

Anyway, we are starting with staff logins, and then moving to end user logins on our various systems offering, and even recommending, two factor authentication.

P.S. Yes I waited more than 5 minutes after taking that picture so that even if you know my username and password you cannot use the code. And yes, we also protect against replay attacks on the code.

P.P.S. After some feedback we now only show the QR code until the installation has been confirmed, then it is no longer shown. That means the SMS codes and the authenticator codes use different seeds so we can tell which was used (and check for a clash just in case). Thanks for the feedback, this helps security.

Tuesday, 29 November 2016

Evaluating a VPN provider

At A&A we are looking in to how we can best help customers exercise their human rights for privacy and rights to net neutrality and to access to legal content.

The IP Act puts in place horrendous snooping powers, and the DE Bill as proposed puts in place a new national censor with the job of blocking porn sites - legal porn sites. We can all imagine how much further such proposals could go.

At present there is no ban on operating a VPN - it would be hard to ban without also banning https used by many web sites and businesses and banks and the VPNs used by industry and even parliament.

There are VPN providers now (sensibly) targeting the UK market - they provide an VPN endpoint which you connect to from your computer or using a router that can do VPN for your whole house. They make a point of having equipment and legal entities in countries that do not require logging and snooping, and make a point of not recording anything or accepting orders from governments like the UK.

So, the next question is how we evaluate VPN providers and even make some recommendations. We may even set up a VPN operation ourselves (well, not ourselves, a foreign company with foreign servers, so no subject to UK jurisdiction).

These are this obvious aspects I can think of, but keen on other comments.


One simple aspect of the service and the devices you choose to operate the VPN at your premises is whether the service can keep up with the speed of your Internet connection, such as an 80Mb/s VDSL service.


Obvious one, but you want a reasonable price. Free is great but there has to be a catch some how, so you expect to pay a few dollars a month at least for any reasonable service.


Are they really not logging anything, do they have a clear history of refusing information requests?


Can we really trust them? Very hard to be sure but reputation and how long they have been in business are key factors.


Can they have your traffic look like UK traffic (if that is what you want)? This may be tricky and without it things like netflix may not even work. If someone sets up a service specially for UK use they may be able to convince netflix and others that it is UK IP addresses even if plugged in via another country.


MTU issues, latency, transparency of IP protocols and ports and so on, IPv6. All things that matter from a technical point of view. Ironically, maybe even fixed IP - if blocking/censorship is your main concern.

Openreach/BT Split

As reported by BBC, OFCOM are getting Openreach split off as a separate legal entity from the rest of BT plc.

What do we think of that?

To be honest it is tricky - A&A deal with BT plc for both BT Wholesale and Openreach departments. The latter is for phone lines to support the broadband services we sell. Mostly we are dealing with the BT Wholesale part.

A lot of the reasons behind this are coming from some of the larger operators who have to deal with the Openreach part of BT much more. They are concerned that BT Retail get some preference of some sort. There are concerns over whether BT are investing enough in infrastructure.

I am not at all convinced by some of the arguments, as Openreach had 86% coverage of UK premises for VDSL (FTTC) back in April, and are pushing hard on this. So there seems to be quite a lot of investment in infrastructure. Also, we don't really see much in the way of preferrential dealing with BT Retail at all - it seems they, and Plus net, have as much hassle with Openreach as anyone else.

But the devil is in the detail, and it looks like the new Openreach will be owned by BT Group plc, so there is a source of investment via that route. But this also means one of the big issues still exists - if BT Retail pay lots to Openreach, that has no impact on my BT Group plc shares.

In practice, Openreach is already operated like a separate company - annoyingly so on occasions. This split will actually remove one useful aspect of being one company. At present, when dealing with BT Wholesale they will often blame Openreach (or "their suppliers") for a failure. Legally that could be force majeure (matters beyond their reasonable control) if they were not in fact the same company and in fact blaming themselves. Being able to throw that back at them can be useful and force them to do their job and not just blame someone else.

But otherwise I would be surprised if we see any difference at all from this move - apart from new contracts which gives them a chance to screw us over somehow.

Wednesday, 23 November 2016

Human Rights

The BBC did a good article on the Investigatory Powers Act (which oddly has yet to appear on the web site).

But there is one aspect they did not make that clear...

The headline was :-

"Tech firms seek to frustrate internet history log law"

It should have been

"Tech firms seek to help people exercise their basic human rights"

We all have the right to a private life and family and correspondence,  and that is all people are after here. Nobody is aiming the thwart the law, unless, that is, if the law is trying to take away that basic human right.

So please, BBC, report it correctly. Nobody is trying to break laws, or frustrate them - we are just trying to exercise our human right in EU and UN declarations of human rights - a right to a private life - that is all.

Sunday, 20 November 2016

First they came for the porn sites

If it was not bad enough with the Investigatory Powers Act passing in to law, we are now facing another wave of stupid and dangerous law - the Digital Economy Bill.

Several people have written some good pieces on that - see one of the latest by Jim Killock of Open Rights Group.

What problem are they trying to address?


Seriously, it is not clear what the specific problem is here - but the Government have been after porn sites for a long time. Those of us that are cynical see this as just one more step in censoring the Internet, one small justification for more filters and laws to back them, so that more and more can later be added to the filtering lists over time.

I will be delighted if someone reading this has some concrete evidence of studies showing what problem exists to be solved. Are there any MPs that did not see porn before 18 (or a pig's head maybe?).

Personally I see two issues, the first is younger children inadvertently encountering unsavoury content on the Internet. This is easy to address with existing tools and some education of parents. The second is older children that want to access porn on the Internet but are not yet 18 (e.g. people that are 16, can fight in the army, and can get married and have sex, those sort of people as well as those a few years younger). This is not a "problem" to solve - teenage kids have accessed porn, probably forever, and long before the Internet. The only problem is where they see porn as "reality" rather than "entertainment and fiction", and that is solved by education. No amount of blocking will ever stop a teenage kid accessing porn if they want to and that is a simple fact!

What is the solution they propose?

There are two key parts here, both of which have huge issues.

1. Age verification on porn sites. Unlike whisky selling web sites that have "Are you over 18? Yes/No", they mean something that can actually validate that you are over 18.

This is serious - a lot of people (adults) access porn. It is not unusual. However, the fact that people access porn, and the specific preferences for people's fantasies is very personal information - sensitive personal information which is valuable to criminals, may be very embarrassing, and usable for blackmail and who knows what else. Remember, until surprisingly recently a preference for same sex relationships would make you a criminal suspect! If anything, it is one's sexual preferences that are perhaps one of the main reasons for the basic human right to a private life.

The only real way to do any sort of age verification is to identify the user somehow. This is a huge challenge to do "over the Internet". Almost anything that can be used to identify a person can be copied and used by their teenage kid - and something like a credit card is one of the easiest. Also, bear in mind, kids as young as 8 can legitimately get a pre-payment visa/mastercard now.

No matter how you try - the system will be flawed somehow (what can an adult type or do on a computer that a child cannot copy?).

But no matter what you try - there will be an association of the web site access with the identity of the person accessing it. Steps can be taken to try and avoid this linking together cleanly by some means, but ultimately there will be a link somewhere, and that allows for a huge database of sexual preferences for adults in the UK. That will get hacked or sold or both.

We are talking about a database of the sexual preferences of every UK adult! But I suppose the Investigatory Powers Act allows such a database to be created as well - at least tied to an Internet connection if not a person. This database will tie to specific people.

2. Blocking of porn sites. Only UK sites would have to comply (putting them at a commercial disadvantage and hampering minority groups), so they propose that sites that do not comply can be blocked by an order on UK ISPs.

There is plenty of evidence that trying to block illegal sites that assist in copyright infringement in some way simply does not work. It is a massive game of "whack-a-mole" at best, and totally pointless at worst. This has been tried, and it simply does not work.

But trying to censor completely legitimate and legal web sites, which have financial and legal resources, is going to be a much bigger challenge. For a start, there are a lot of them, a hell of a lot. We are not talking of blocking one web site like piratebay, we are talking every single non UK porn web site that is not going to pay for UK age verification services - they would be much more successful investing in ways for UK "users" to bypass government censorship.

But as Jim Killock points out - the second "age verification" becomes the "norm" for UK porn "users", we see massive opportunity for fraud - porn sites that insist you have to enter card details to proceed and even quoting the UK law on this. Quote a law and link to it and the request seems legitimate. If all of the free sites vanish (unless you try a little to find them), then we will be swamped by the bogus sites collecting personal information. And there is almost no end to how much personal information they can ask for in the interests of "age verification" and a promise not to actually charge your card or log the details. There is no way for people to tell the "real" (and supposedly safe) age verification requests from the bogus ones, and there is a massive incentive for people that are defrauded to keep quiet rather than own up to the site they were trying to access. It will be a secret and undercover fraud that will be a nightmare to track down.

What is the right answer?

You have to assume there is a question/problem in the first place, which is not clear, but assuming there is one - what is the answer.

I think it is simple to say - education is the answer, not censorship.

But I'll try and be a tad more helpful.

For young children you need education of parents and guardians on how to use the many tools available to them, and some education that the Internet is not the ultimate baby sitter. There are many tools - just installing any operating system these days will offer a range of "parental controls". There are safe-search settings on search engines and there are controls that can be set in most ISPs systems that offer filtering as an option. ISP filters tend to be whole house and so a tad crude but there are DNS based systems which are easier to set on a per computer basis and provide controls not only on content but times of day, etc. Lots of tools exist, in the control of the parent/guardian. Yes, they are easy for some teenage kid to bypass, but we are talking here of young children not trying to access porn, and for that all of these tools work well.

For older children that want to assess porn the first thing to realise is that there really is no point trying to stop them doing so - it will never work, sorry. But education matters. Along with sex education you need education for teenagers about porn! I know it seems odd, but teenagers need to know porn exists, and that every type of porn and sexual preference you can imagine (and many you cannot) exist somewhere. They need to now that porn is entertainment and not reality. That it is fiction. That there are many things out there, with which they may feel uncomfortable, and that they have the choice of what they look at and what they do not. And that most of all they need to understand that it is not in any way a guide to any real relationship, just as many fictional and entertainment films are not a guide to real life. With some basic education people can enjoy porn, avoid things they do not enjoy, and still have meaningful sexual relationships in the real world.

Saturday, 19 November 2016

IPv6 and Zen

With my FireBrick hat on for a change, one of our customers has a Zen line with IPv6

He was surprised to find the IPv6 was not working when using a FireBrick FB2700, and so was I!

As usually, within a couple of hours of reporting the issue, we have new code that solves it, even on a weekend. I have to say though that I was impressed that Zen looked at the FireBrick web site and manual in an effort to help their customers with this. Well done guys.

For so long FireBrick has been used on A&A lines for IPv6, it is nice to see how other people do it.

The problem is that the protocols used for this are horrid. I think I mentioned this before. I really think a PPP level negotiation would make a lot more sense. I even have my name on a draft RFC, but no luck on that.

What happens is, after the IPV6CP negotiation for a 64 bit interface address, you can then send IPv6 using the FE80:: based address. To get any real IPv6 addresses works a lot like a LAN but with extra bits. You can get Router Announcements on the PPP, and pick an address and you can use DHCPv6 to request an address and prefixes for your LAN.

Traditionally, as it seems the most common way, FireBrick used the latter - expecting the DHCPv6 to allocate a "real" address on the link itself (maybe) and a prefix for LAN. We actually ask for one or more /64 prefixes for different LAN interfaces as configured, but by default it is all of the interfaces we have. You can configure which interfaces to use with which PPPoE links though, if you want.

We have a bug where the IPV6CP forced a new interface address, which Zen do, specifically 00:00:00:00:00:01 for some reason. We were not then using the right FE80:: address for DHCPv6, or rather not accepting replied to the address we were using due to a silly mismatch of the two.

It also looks like Zen do RA for the PPP side address, and DHCPv6 for Prefix Delegation, which sort of almost worked. We had some bugs. For a start, we did not handle "infinity" as the validity for these (even though that is what we requested), silly error, but it meant we expired every allocation one second before we got it! Took me a while to worth that one out...

We also did not handle a case of asking for a prefix even if no interfaces are set up to use it (e.g. where Zen is a secondary ISP on separate routing table).

However, with a few tweaks we have it sorted, only using DHCPv6, not RA, but picking an address for PPP link from the delegated addresses and requesting at least one /64 by default.

Obviously, we are happy to test with other ISPs and make sure we work. IPv6 should "just work" with a default config with any ISP, not just A&A.

Our customer now says IPv6 wastes a lot of time - not because of any difficulty setting up, but because he just spent an hour playing which is only on IPv6.

Well done Zen, the world is gradually moving forward. A&A started doing IPv6 in 2002.

Friday, 18 November 2016

Snooper's Charter and A&A

First off - I appreciate that my blog is not an official statement for A&A, but I have linked the status page here to give you an idea of my thoughts on the matter and how that may play out for A&A in due course.

Summary: Watch this space - more to come over coming weeks.

I have commented many times on the Investigatory Powers Bill, and submitted written evidence to parliament as well as oral evidence to the committee. I have attended meetings with privacy groups and legislators. I have spent a lot of time on this. I have tried very hard to try and get some degree of sanity in to this legislation, and I am sorry to say that on the whole I have failed to make any real changes, sorry.

Once we see it, I am planning to go through the final wording of the Act, with a lawyer friend of mine, and we are going to try and make sure we understand the nuances that finally made it in to law. Once we have done that I do plan to write up something much more comprehensive.

But how does this impact A&A and the services offered.

As I say, this is not an official statement yet - we'll be posting more details of what we are doing and when as time goes on. At this stage there is nothing that needs doing urgently - it will take time for anything to happen in relation to the new Act and a lot of time (and money) for the monitoring and logging to get in to place.

It is also worth pointing out that I don't really have a real problem helping the police investigate crimes as long as there is a proper oversight and control.

In practice a lot of the Act relates to the intelligence agencies, and whilst there a lot of problems with this, it is unlikely we can do much now, or that we would be impacted by this aspect of the Act. However, some of the steps we can take for privacy thwart those parts of the Act too!

The real issue we see is the huge invasion of privacy in collecting and storing data on innocent people - and the bulk powers for "data retention" do just that. They are designed to allow lots of personal information to be gathered on everyone - so mostly people completely innocent and almost entirely people not even suspected of a crime in any way. This is compounded by systems to search through that data over many ISPs and provide it to a wide range of people including the police, without a warrant of any sort.

We expect that it is very unlikely A&A will be asked to do anything - this is because companies like BT and Talk Talk will be asked (ordered) to and that will allow deep packet inspection in the back-haul networks that are used by A&A (and most ISPs).

So what can we do about that?

One of the biggest things we can do is provide information and advice about exercising your basic human right to a private life. This will take some time to put together in detail once we fully understand the legislation. We will start a specific section of the wiki pages as well to cover ideas people have. We are interested in suggestions people have too.

There is also a good possibility that we can engineer some services that operate in a way that bypasses the logging. A simple example would be an outgoing email server that is esmtp only (encrypted) to a service that is outside the jurisdiction of the UK and new law. This would be servers outside the UK and also set up in a way that A&A, or any people in the UK, technically have no control of them. This means that nobody under UK law could be required to comply with an order to include logging on those servers. As an ISP we, or BT/TT, would only see encrypted esmtp traffic to that server and hardly any useful meta data on the emails and nothing on the addresses involved.

Of course, even something simple like this suffers the big problem that the person at the other end of such communications (e.g. emails) will not have the same degrees of security and hence allow logging of meta data at that end. This is always a problem with any communications.

There is also a lot of advice on the use of tools and apps that help - like signal and tor. Sadly even tor has limitations and performance issues.

One answer is VPN services with endpoints outside UK jurisdiction but still reasonable latency. This is hard to scale up - but we are already talking about this in the FireBrick dev team about this.

In the short term we are seriously considering a trip to Iceland to investigate data centres and transit there - perhaps installing some tin that can run VMs as needed - but we also have to investigate the exact way such servers can be outside our control and hence not subject to orders on us to add data retention or intercepts under UK law.


It is, of course, right for everyone to expect to be able to exercise their human rights, including the right to privacy. There are a lot of people, in light of this incredibly intrusive new legislation, that wish to do so, and so there will therefore be a lot of companies working on ways to provide (sell) services to help people do that. These services will have to be designed to be outside UK law, obviously. But this means they are also outside the law where there is a specific suspect of a crime, and a more reasonable justification to provide intercept or collect data to help law enforcement (with suitable warrants). So by encouraging people to need privacy and encouraging companies to offer privacy you actually make fighting crime harder. It is worth bearing in mind that serious criminals have always been able to avoid this type of monitoring, but more and more normal people and, occasionally, those committing minor crimes will find it easier and easier to use services offering privacy now.

Wednesday, 16 November 2016

More on Live TV from my man cave

SkyQ is fucking useless - it did not record tonight's live RT UK News interview. It is a heap of shit is so many ways.

Update: Someone managed to record it - thank you.

However, I am pleased to report that doing a live Skype TV interview worked well.

They texted me with around 30 minutes notice - the Skype login did not work - the camera was not set up and then did not see the lens but instead of telling my it just caused the app to freeze, the headset cable did not work, and I had to reboot the Mac, and well, those 30 minutes were busy.

However, the good news is that, in the end, the audio worked properly simply by selecting 48kHz as a USB audio device. The room is a tad echoey, so that needs improving but the H4n pro worked for audio.

Also good news is that the 1DX MkII with a 24-70 f/2.8 L lens worked well with the BlackMagic HDMI box to provide full HD. The picture, as broadcast was crystal clear and clearly HD and looked excellent.

I am well underway to having a decent studio here in the man cave for TV interviews, and I think I did quite well being live on air at 30 minutes notice to be honest.

Only snag was audio in my earpiece went to zero just as we went live, I wonder if the volume control caught on my collar or something, fixed, and was live a few minutes later. Well done coping RT...

The only sad part was that the topic was the IP bill finally becoming an Act. Sad days. More on that when we have reviewed the final text.

Tuesday, 15 November 2016


Dreams are weird shit, aren't they. This is one of those areas where different people can be very different, as I understand it. I am one of those people that can occasionally remember dreams - usually if I somehow wake up during a dream. My latest medication woes have meant different sleep cycles and dreams, but overall for the better I think.

I have to say that I do wonder what the underlying evolutionary process is that created the state of dreams we experience, and as I understand it is experienced by animals as well. There is some logic in the idea that it is a way for us to review our experiences and "safely" try many possible strategies and see how they play out. This makes some sense, but dreams have a whole load of sanity checks turned off.

Obviously, the most basic disconnect in a dream is our actual control of our body - we may move our eyes, but for most of us we are not actually moving our muscles otherwise and getting up and walking around and doing shit - we un-plug our brain from the world for a while. Errors in that process lead to sleep walking, and the rather odd moments we can experience as we wake up some times.

To some extend that makes sense - if this is the ultimate role playing experience to try out scenarios and work our strategies for the future. I have dreams of upcoming events, whether a meeting with BT or a live TV broadcast or, well, anything new that I know is going to happen. I expect these dreams help me prepare. I also have dreams of coding and solving puzzles. Some times (as I have blogged) theses really work to find the answers. The other day I was designing an XML system in great detail for creating a comedian's script to tell jokes, in a dream - I have no idea why!

But what puzzles me is how dreams (at least for me) also un-plug so many "sanity checks" on reality. So many things can happen and not be questioned.

So, one of my latest dreams for amusement:-

The idea of flying is not uncommon - but for me this is a recurring theme where I cannot actually fly but, with a lot of mental concentration, I can sort of hover several cm over the ground and then sort of "glide" along the ground.

In this dream people can do that - not many, but I can. It is seen a lot like skateboarding - something some people can do well (not me!). There are kids that do it recreationally, in like skateboard parks, but if you saw someone doing it in the street you would think a bit childish and maybe even a bit dangerous.

In this context the fact I can do this is a bit of showing off, occasionally, but not seen as a very useful skill. Obviously someone doing the long jump would be cheating when using this skill, but that was about it.

Now, the weird bit is that in the dream I realised it was impossible - it made no sense in terms of laws of physics, and it dawned on me that it meant that the universe in which I lived was fake!

I was realising that the universe was some sort of simulation or something fake and not real as I had an impossible ability!

What was strange is that in the dream I did not make the leap that the reason the universe was fake is that I was in a dream! I was thinking simulation with a bug in it somehow.

As I awoke I had what seemed like several seconds of dread that the real universe was fake because I could do something impossible, and a sort of double take that no I cannot really float a few cm over the ground.

So yes, some times dreams can be fun!

P.S. I like someone commenting to me of dreams of "no pants", not a dream I have ever had, having spent some of my youth living in a naturist club where such was clearly not an issue!

Saturday, 12 November 2016


We live in a strange world where some times we share personal information and sometimes we don't and sometimes it is a problem and sometimes not. There are those that will say I should not have said I was diabetic in a previous blog post.

To be honest, I find the lack of information, and/or overwhelming information, on the Internet to be an issue when facing some of the challenges of growing older and more broken over time. So I hope these occasional health related blog posts can be of interest to those who find themselves in the same boat as me in the future.

For a little while I have been on some blood pressure medications. I was originally not at all keen on this, but apparently high blood pressure is a "silent killer" and so it is important. The thing that swayed me was when I realised that my higher blood pressure was actually related to some headaches. I found I could not drink more than a certain amount without suffering with a crippling headache all night - nothing like simple de-hydration, and very binary - below a certain level was fine, above it was agony. Being a tad scientific I got an optic for my whisky bottle so as to understand how much I was drinking, and over time the amount I could "safely" drink got lower. Only when I was put on blood pressure medication did I realise the connection - some Perindopril and now Ramipril made all the difference. But over the years things have progressed, and so something more was needed.

I was put on Indapamide 2.5mg which works somewhat differently, and, well, works well on the blood pressure - too well in some ways! I have my first review of this with the diabetic nurse this week, and we'll see what she says - I'll add to this post.

Yes, I can drink what I like, but there have been a few odd effects. To start with, as they suggested, a lot more going to the loo, but that settled down. Headaches for a couple of weeks, but that has cleared up. Initially blood pressure somewhat all over the place, nearly passed out at one point. Again, settled down.

Overall, after a few weeks all I am left with is issues with low blood pressure (100/70) which mean standing up quickly, running up stairs and cycling up hill, are causing me problems. I hope we can address this with review of the medication and dosage.

But there is one really weird change - my blood sugar rising (one of the listed symptoms) meaning I have gone from 38 units a day to 56 units (so far) to try and address high blood sugar some of the day. However, oddly, I am actually finding myself much more awake and "with it" all day now, and sleeping just as well at night.

So overall, if you are put on Indapamide, I would say you may well have a few weeks of hassle in various ways. I got through quite a lot of ibuprofen in the first few weeks, but overall, it really works.

I hope this post was of some use...

Update: They don't have 1.25mg available, but do have a combined perindopril 5mg and 1.25mg indapamide combination - so trying that. Wish me luck :-)

Wednesday, 9 November 2016

Brick wall BT

Hurry up and build that wall, Trump, I want to bang my head against it as it would be easier than BT...

So, simple BT fault, suspected issue on fibre back-haul from an FTTC cab, started after MSO, so probably damaged to dirty fibre. Not a complicated fault at all.

Symptoms are idle levels of packet loss all day, sometimes peaking to 20%, that is shitty!

The dialogue sort of goes back and forth, but we finally go somewhere, after escalation, with a clear statement from BT:

'We have run diagnostics and can see numerous code violations which will require an engineer to liaise with 2nd line DCoE if the fibre escalation team are unable to assist.'

That is pretty clear, so we ask them to fix it.
  • Us: Please fix the fault.
  • BT: You need to book an SFI
  • Us: An SFI is an optional service to check the metallic path to SIN349, nothing wrong with the metallic path here, so silly, just fix it
  • BT: No, you have to book an SFI, that is the process
  • Us: OK, what is the process for fixing this fault without ordering an optional service.
  • BT: There is no other process
  • Us: Are you really saying BT have no process to fix this fault without ordering an optional extra service - if so that is breach of contract as contract says you will investigate and fix faults
  • BT: We don't see a BT fault
  • Us: OK, so you are saying a line with constant loss peaking at 20% is acceptable, is that the formal standard BT work to?
  • Us: What actual investigation did you do, and to what standard or reference did you test the line so as to decide there was no fault?
  • BT: If you want us to investigate the fault report you raised further then please book an SFI
  • Us: No, the contract says you will investigate and fix faults, are you refusing to?
  • Us: Repeat of questions about this being "not faulty" at 20% loss?
I'll add some more as it goes. But it goes round in circles.

Either BT

(a) consider this to be acceptable level of service, in which case, especially with ideas of universal broadband service obligations and automatic compensation, we need to take this up with OFCOM, BIS, and the Digital Economy Bill parliamentary committee as a matter of urgency.

(b) accept that this is a fault and BT are breaking contract by refusing to investigate and fix it.

BT just need to pick one and stick with that story to the end. Either that or just damn well fix the fault!