In the UK, BT are transitioning their entire service platform over to new infrastructure. They call the old platform "20CN" for 20th Century Network, and the new platform "21CN" for 21st Century Network.

The way the upgrade works is that BT install the new equipment in the local exchange (or central office if you're in the US). The ISP and BT then organize migrating the DSL service over to the new platform, which involves BT setting a target date for that to happen. Once everyone has been migrated over, the 20CN DSL support is removed to make room for more new equipment, and BT eventually moving the voice service over to the new equipment.

BT leads you to believe that the migration process takes ten minutes.

They used to have a website which told customers when they planned to switch over and other details, but when I checked it recently, it didn't respond.

This process has been planned for at least the last two years, and our local exchange had the new 21CN equipment installed at the end of January.

Our ISP immediately put in an order with BT to migrating our line and two others on this exchange over to the new 21CN equipment, and BT committed to migrating it over on 27th February, today.

However, at 00:40 GMT today, all connectivity (including DSL modulation) was lost, and some 19 hours later, we are still waiting for progress. However, voice services on the phone line is intact (which basically means that the copper pair back to the exchange is still there). It is almost although someone has pulled the connections to the DSLAM at 00:40 and left it at that.

According to the BT's Install Report for the 21CN service, the migration is still "open" and "committed", and so can't have a fault raised. The ISP has tried to raise a fault report this morning against the 20CN service, but BT has closed this saying that the line is no longer 20CN.

Other people on our local exchange have been migrated within the 10 minute window this morning, so it looks like we've basically been forgotten mid-migration.

Having just spoken with the ISP, they are saying that we need to wait until today has past, by which time BT should have failed the migration to 21CN. At that point, they claim they can raise a fault report (which sounds fishy to me - if BT know it's failed to migrate, why do they need a fault report to fix what is essentially their own brokenness. For more such fun with BT and DSL, see dwmw2's Advogato diary.)

This unfortunately means I find myself in the position where I am unable to work - since I require internet connectivity to receive email containing kernel patches, download kernel tree updates or upload my kernel updates. Great some people may say, but I've already had three (Wednesday,Thursday, Friday) busy non-working days which count as my "weekend" and now when I need to work on the kernel, I'm stumped. Thanks BT.

Update 28 February 2009
The ISP now says "our 21CN migration department is now closed, there's nothing we can do, please call back Monday" which is contary to what was said yesterday.

I enquired about using dialup, and the ISP gave me their dialup number. However, they also explained that BT may have ripped out the 20CN equipment which provides their service. Upon trying it, the modem connects and I see the LCP packets from the remote end. However, the remote end ignores everything that I send. According to the initial LCP ConfReq packets, it strangely wants CHAP authentication which is very unusual in the UK for dialup.

I've confirmed that my end is fine by using a NULL modem cable and setting up my PC with pppd in passive mode, and everything works correctly. So I can only think that the equipment terminating the PPP connection has been deconfigured or somehow blocked. (As I understand it, the dialup connection is terminated in the local exchange.)

Update 1 March 2009
Having walked over to a friendly shop to use their internet connection to look at the latest information on the BT Install Report, it now says that the migration has been delayed. It gives a reason for the delay as well: "DELAY IN PROCESSING". It is obviously left to the reader to work out what that means.

However, you have to ask yourself the question: why, if BT are unable to complete a migration, did they even start the migration process, and why don't they have a method to revert back if they find they can not complete.

Maybe I should start coining dwmw2's very pertinent and relevent three word description of the UK's monopoly telco.