Changes to BT Wholesale IPstream max products
Monday 14 May 2007 16:33:04 by Andrew Ferguson
As part of a set of changes to Quality of Service controls on the BT Wholesale IPstream Max and Max Premium products, extra BRAS Data Rate (IP Profile) settings are to be introduced.
The Max product which is used for millions of UK ADSL connections is to have some tweaks that may improve the experience for people who connect in the speed range of 250Kbps to 2Mbps. There is a setting applied to each line, in addition to the basic sync speed the ADSL modem connects at, called the IP Profile (sometimes referred to as the BRAS Data Rate) which controls the speed a which data can be downloaded. It is used both in the dimensioning of the backhaul from the exchange as well as the Quality of Service (QoS) settings which allow an ISP to book an assured rate for a specific period on a line.
Currently there are sixteen IP Profile values possible, with an additional four at 350Kbps, 750Kbps, 1250Kbps and 1750Kbps to be added on 31st July 2007 (the current settings are documented in one of our FAQ's). This should mean that someone now syncing at just under 1152Kbps, e.g 1056Kbps would get an IP Profile of 750Kbps, rather than the 500Kbps they currently get. No changes have been announced to the way the IP Profile waits for three days before increasing to match the setting for your current sync speed.
Any speed boost is a welcome one, and while the changes will not break speed records for those on long lines, any extra speed is welcome. With ADSL2+ pencilled in by BT Wholesale for 2008, we suspect that these tweaks to the IP Profile may be the largest speed boost those living a fair distance from their exchange will see for some time. This is because ADSL2+ will only give marginal improvements on lines over around 4.5km in length, unless options like Seamless Rate Adaption (SRA) and bonding are employed.
The main reason for the changes appears to be that services that make use of the QoS capabilities were wasting more of the ADSL speed than need be. QoS sessions are something broadband consumers do not see much. Generally it is only used by products such as BT Vision, where a stable download speed is needed to ensure a video stream is watchable. When an assured rate session is booked, checks are made to ensure capacity is available on the customers line and the exchange and only then is the assured rate provisioned, after which this reserved bandwidth will become immune to exchange based contention.
Digg this
Add to del.icio.usComments
A useful improvement on longer lines, where MaxDSL has been a lot of benefit since its introduction a year ago.
I wish there could get extra ip profile from 7150k to 7500k and extra uploads from 448k to 700k
staff member)
about 1 year ago
Extra upload is available if you purchase a Max Premium product which offers upstream sync speeds of 832Kbps for an extra £5 per month at the wholesale level.
No point in creating a 7500Kbps IP profile, since with 8128Kbps sync, once the ATM overheads are allowed for 7150Kbps is about the most you can manage.
Hmm, not too keen on the profile sectors above 1152. By which I mean, currently there is a profile at 1152Kbs and 1728Kbs (1Mbit & 1.5Mbit) with two new ones at 1250 & 1750 they seem too close to each other especially when I can sync just below 1728 at times. I would've prefered to see the 1750 one be around the 1600Kbs mark so that there isn't that big drop down to the 1Mbit profile...
staff member)
about 1 year ago
1152 sync gives 1Mbps profile
1440 sync gives 1250 profile
1728 sync gives 1500 profile
2016 sync gives 1750 profile
2272 sync gives 2000 profile
Ah right, that makes it clearer. :o)
Thanks Andrew
I find the last paragraph rather disconcerting. If BTw are ringfencing exchange bandwidth for BT Vision without increasing the overall capacity it will clearly lead to higher contention for others on the exchange.
Considering the number of complaints about BT commencing throttling which coincided with the BT Vision launch I seriously doubt that there will be any such capacity increase.
I thought BT and BTw were supposed to be different companies - how can BTw get away with introducing QoS which appears to only benefit the BT Vision product - unless anyone knows better of course.
Worth a mention, QoS only really kicks in if there's congestion on the uplink circuit...
Presumably BT Vision is based on a wholesale product with Quality of Service conditions, that any ISP can buy.
So years after the introduction of adsl max and quite possibly a big % of consumer fault reports/complaints the slow BRAS profilge increases are not adjusted to 75 minutes.