Tuesday, 13 December 2011

Unhooking BRAS

That got you :-)

Looks like our favourite telco are no longer running the silly BRAS rate system on 21CN lines. Not seen a briefing yet, but it was mentioned in an ISP forum some time ago.

Previously the BRAS rate was set by some config which was based on a back end system that sent updates based on changes to sync rate. The system could take hours to apply changes, and the rates were from a set of fixed values (in some cases in 1M steps). This meant people had delays getting updates after a sync change and meant losing up to 1Mb/s because of the steps. There were also issues where the databases did not agree or the updates did not happen.

What seems to be happening now is that the BRAS rate is set based on the sync rate on every connection. We have updated our systems to match this.

So, they have finally unhooked the BRAS on 21CN.



  1. Hi - been runing KBD on various lines this morning, still seeing profiles applied - how are you identifying the lines where BRAS profiles are no longer applied? Does they dsplay something different in KBD results from BT?

  2. Only for 21CN, and we are seeing BRAS for KBD as just a number, close to the sync rather than the usual adsl5500 or some such you see on 20CN.

  3. Good, that finally has my FTTC profile speed saying something sensible on clueless.

    Interestingly I parsed "Unhooking BRAS" title as having to do with telecoms, not female garments until I looked at the "that got you" comment. Context is a wonderful thing....

  4. Wow, my line FTTC line has gone from 23M to 38.9M. Just a 'bit' of an increase there!

  5. The last line in the article says "These changes are particularly useful when they apply together as we have seen FTTC lines gain significant speed (e.g. 30M to 39M) and not update BRAS rates."

    So we're getting bigger BRAS then... :-D

    (I'll get my coat)

  6. Well, I can't argue with that :-)

  7. Just gone from 3.5M to 4.64M, which is the best ever seen from my house :-)

    [As for 38.9M, well UFO abduction is more likely round here]

  8. Seeing as I work for those who may be at fault I never see the word BRAS as anything else. Especially when I am doing research (of the correct work type) using my work laptop and keep hitting the firewall telling me I am searching for inappropriate content! Also my exchange area is fully FTTC enabled apart from my CAB even though it has some 300+ workers served by it and virtually all are ADSL enabled, a certain company in its wisdom thought the CAB us uneconomical to provide FTTC service (and its around 300 metres from the fibre spline – all ducted! :-(

  9. The FTTC speed upgrades are not related to this change. We have deployed a new band plan that doubles the speed for most people on FTTC. More to come on band plan bandwidth options in the new year.


  10. That is cool, Neil. If there is any briefing you can send us that would be nice.