AAISP Hits BT Over Bonded ADSL Bug
Posted: 04th Jun, 2004 By: MarkJ
The UK ISP Andrews & Arnold (AAISP) has today sent us a detailed clarification regarding the impact of 'source filtering' (sf) on bonded IPStream based ADSL services. The method, which helps to prevent IP spoofing, has caused a few problems and AAISP isn't best pleased with BT:
Several smaller ISPs are bonding multiple ADSL lines to provide additional uplink capacity. We (AAISP) have customers with 2 and even 4 lines bonded to provide 500Kb/s uplink or 1Mb/s uplink, including a health authority with several sites. Typically customers have a 2Mb/s line and 1 or more 500K lines for extra uplink. We even have a special low cost tariff for these extra uplink only lines.
The principle is simple - packets are sent on multiple lines (shared out between them), but still use the IP addresses routed down the main 2Mb/s line. The new feature BT have introduced, without any consultation, means packets will no longer go up any of the additional lines.
At AAISP, we have more than one BT Central (our end of the ADSL link) and so we are able to put different lines on different BT Centrals so we can still do bonded uplink - but it has meant a lot of reconfiguration for us and customers to make this all work and placed some limitations on what we can do.
We know of other smaller ISPs with only one link that also do uplink bonding and who will be seriously affected. We also know of end users doing this between different ISPs and now finding they cannot.
What BT have done is a really good idea for most broadband lines, and something we asked about years ago when ADSL first launched. We were told then that BT would/could not do it and security was our problem not theirs.
The problem is that we were not consulted in any way on this, and the planned engineering works stated there would be no customer impact and so was ignored. It came as a bit of a shock and has caused us embarrassment and our customer some hassle. If BT had consulted us we could have explained the issues and at least have been ready. What is needed is some way to disable or restrict this feature on individual lines where there are additional blocks routed via other means. BT have not provided any such means, any consultation or any help.
The latest from BT appears to be a briefing stating that what we are doing is an unsupported feature - yet BT have provided no evidence of what is and is not a "supported" feature to back this up and avoid any future problems.
What makes it particularly strange is that BT have been supporting us as an ISP and FireBrick manufacturer in promoting "uplink bonding", and even hosted a seminar on this topic in a BT building recently. To do all this and then pull the rug from under our feet is just crazy.
At AAISP we can cope with this change, just about, but is this really the way BT should be doing business?
We wholeheartedly agree with AAISP, especially when considering that BT was clearly aware of providers offering this and didnt even bother to consult them, potentially causing loss of business.
Several smaller ISPs are bonding multiple ADSL lines to provide additional uplink capacity. We (AAISP) have customers with 2 and even 4 lines bonded to provide 500Kb/s uplink or 1Mb/s uplink, including a health authority with several sites. Typically customers have a 2Mb/s line and 1 or more 500K lines for extra uplink. We even have a special low cost tariff for these extra uplink only lines.
The principle is simple - packets are sent on multiple lines (shared out between them), but still use the IP addresses routed down the main 2Mb/s line. The new feature BT have introduced, without any consultation, means packets will no longer go up any of the additional lines.
At AAISP, we have more than one BT Central (our end of the ADSL link) and so we are able to put different lines on different BT Centrals so we can still do bonded uplink - but it has meant a lot of reconfiguration for us and customers to make this all work and placed some limitations on what we can do.
We know of other smaller ISPs with only one link that also do uplink bonding and who will be seriously affected. We also know of end users doing this between different ISPs and now finding they cannot.
What BT have done is a really good idea for most broadband lines, and something we asked about years ago when ADSL first launched. We were told then that BT would/could not do it and security was our problem not theirs.
The problem is that we were not consulted in any way on this, and the planned engineering works stated there would be no customer impact and so was ignored. It came as a bit of a shock and has caused us embarrassment and our customer some hassle. If BT had consulted us we could have explained the issues and at least have been ready. What is needed is some way to disable or restrict this feature on individual lines where there are additional blocks routed via other means. BT have not provided any such means, any consultation or any help.
The latest from BT appears to be a briefing stating that what we are doing is an unsupported feature - yet BT have provided no evidence of what is and is not a "supported" feature to back this up and avoid any future problems.
What makes it particularly strange is that BT have been supporting us as an ISP and FireBrick manufacturer in promoting "uplink bonding", and even hosted a seminar on this topic in a BT building recently. To do all this and then pull the rug from under our feet is just crazy.
At AAISP we can cope with this change, just about, but is this really the way BT should be doing business?
We wholeheartedly agree with AAISP, especially when considering that BT was clearly aware of providers offering this and didnt even bother to consult them, potentially causing loss of business.
Latest UK ISP News
Cheap BIG ISPs for 100Mbps+
Community Fibre £21.00
Virgin Media £26.00
Shell Energy £26.99
Plusnet £27.99
Zen Internet £28.00 - 35.00
150,000+ Customers | View More ISPs
Cheapest ISPs for 100Mbps+
Modest Availability | View More ISPs
Latest UK ISP News
Cheap BIG ISPs for 100Mbps+
Community Fibre £21.00
Virgin Media £26.00
Shell Energy £26.99
Plusnet £27.99
Zen Internet £28.00 - 35.00
Large Availability | View All
Cheapest ISPs for 100Mbps+
Large Availability | View All
Helpful ISP Guides and Tips
Sponsored Links
The Top 15 Category Tags
- FTTP (5543)
- BT (3518)
- Politics (2543)
- Openreach (2301)
- Business (2268)
- Building Digital UK (2248)
- FTTC (2046)
- Mobile Broadband (1979)
- Statistics (1790)
- 4G (1670)
- Virgin Media (1625)
- Ofcom Regulation (1467)
- Fibre Optic (1396)
- Wireless Internet (1393)
- FTTH (1382)
Sponsored
Copyright © 1999 to Present - ISPreview.co.uk - All Rights Reserved - Terms , Privacy and Cookie Policy , Links , Website Rules