Thursday, 2 August 2012

Slow internet?

[Pauline, you can skip to the last paragraph :-)]

The good news, for A&A customers, is that we seem to be coping fairly well with the 'lympic traffic. Yesterday saw the first slow down during the day on some LNSs from around 15:30 to 16:00 with some slight signs of congestion all afternoon. This will not be ideal for our link stats, but does look like we coped quite well. I'll be interested to hear from any customers that noticed any issues.

However, it is easy to forget where we start with the broadband we have in the UK and specifically A&A. We are all used to latency in the 10ms to 20ms ranges. Yes, some are slightly higher if you are on a slow line with interleave, and obviously while filling a link it is a different matter, but none the less, pretty damn good. many customers even have consistently lower latencies these days.

What has surprised me is the Internet we have in this villa in Greece where I am staying. The villa is nice, with wifi all over the place and Ethernet sockets all over the place. But the first hop has silly latency. I am thinking it has to be some sort of mobile connectivity, but have yet to find where the utilities are and take a look.

The latency on 100 pings is like this:

100 packets transmitted, 100 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 79.712/691.432/1382.148/351.071 ms

Now, that is a pain for all sorts of reasons. For a start, much of the time, it is well over half a second, which is enough to make even simple ssh a pain, but it is horribly variable and spiky. Sometimes almost usable (80ms, as you see). I have seen over 3 seconds on occasion too. The throughput looks close to a 1Mb/s but hard to be sure. There is low packet loss (often pings show 0% as above).

I am told that this is the sort of crap that is normal for a lot of people - how does anyone live with this? Our monitoring systems at A&A do not even scale the graphs to show over 500ms and only show that for when there is a fault or a full router queue. We have raised major issues in BT where latency has risen by 50ms on lines for periods of the day. We have raised major issues that BT had to raise with router suppliers for occasional 100ms latency spikes. No idle A&A broadband line could ever look like what I have here in Greece.

Of course, latency is one of those things rarely mentioned. I am sure, if I asked, I would be told how this villa has several megabits of Internet access, and that may even be true.

I should have brought a FireBrick and worked on coding a variable latency link that has local TCP processing at each end.

Anyway, apart from that, it is hot. Seems a nice enough place. Very remote - near Lindos, a village that seems to have no Rhodes^WRoads, i.e. is totally pedestrian. Very nice meal at a local restaurant last night. And the aircon works in the Villa, which is probably more important than the Internet.


  1. >>I am told that this is the sort of crap that is normal for a lot of people - how does anyone live with this?

    If the only viable/affordable alternative is "none" - then the choice is made for you... I'm working with a customer in Africa and normal ping time to him is in the 1000-1500ms range - if the link to him is busy, that can easily double... the alternative for him to the local ISP ($10/mo) would be VSAT (most definitely not $10/mo)

  2. 500ms is about what you'd expect to get via a satellite link, are you sure you are not connected via satellite?

    1. It was way too variable for that