As I say I don't think its as simple as a disconnect reconnect because BT routing is a law unto itself from what I've read.

While ISPs can and do hassle BT over individual customer issues I don't think they have the influence on BT to change their business processes or network unless they all band together and threaten to switch to a different supplier, this cannot happen until LLU becomes as ubiquitous as BT so for the moment BT can adopt a take it or leave attitude because no ISP can really afford to exclude customers on BT only exchanges.

In reply to a post by mixt:

What caused an hour of 'dead lines' ? Was it the BT outage? (which for me, only lasted 20 mins) or was it Zen performing the load balancing after the BT outage? What is happening for lines to remain 'dead' for hours? Is it the fact routers land up with one of the 172.* IP addresses from BT, think they are connected, and so don't log back in?

Zen's Load Balancing.

Basically leaves the sessions stuck. Even full power cycling a router doesn't fix it (so it's not the stupid BT auto-assign 172x stuff (although I hear rumour it is only supposed to keep that session for 15 minutes)

You power cycle, sync comes up, PPP refused.
OR
PPP accepted, but then dropped shortly after before any packets are transmitted.

Stale sessions would occur no matter when the load balancing was done, due to a BT issue.

Ahh yes, I think I know what you mean now (I remember something similar from when I worked at a small ISP up north).

Basically, the routers keep trying to reconnect (in the case of PPP sessions which connect, but then drop) or, in the case of being assigned a 172.* address, BT's systems will then drop the connection again after 15 or so minutes (I have also been told this) forcing the router to reconnect to hopefully login correctly.

But, if the actual session becomes stale, the router can attempt reconnection again, and again, and again, for up to something like 20 or so minutes, before it then clears within the BT system, and then things return to normal. I suspect this is what you are talking about, right? Stale sessions within the BT network itself. We were always told that leaving the modem off would clear stale sessions after 20 mins. But what we usually did was call some special BT support number, give them the broadband/land line number, and they would clear the stale session for us. Either way, a right royal PITA to be honest.

I agree, it's all a bit of a farce to say the least. I don't think I've yet to experience a stale session (have they resolved them on 21CN? Is it still mostly a 20CN problem?), but the way my Linux router behaves, it basically aims to keep the PPP session up, continuously. If it drops, it will attempt reconnection. If it times out, it will drop, and attempt reconnection again. If it connects, and gets a 172.* address (I check this every minute via a crontab), it drops, and reconnects again. It basically does everything it can to bring the link back up, checking that it is connected to A&A as expected.

I guess other off the shelf routers aren't as smart as this, and I appreciate how this can create the issues you describe. I can't offer any advice other than - my take on it all is as I've stated before: BT is the lowest of the low, it is the broadband infrastructure for the masses. I do genuinely expect it to be below par (or for what of a better word, s**t) compared to other offerings from other providers (like LLU etc). But I can live with the outages and PEWs (which are rare, or performed at night). But I guess other's can't, and that's understandable if you are a business where your only option is BT based connection, with 20CN being an even worse deal!

In reply to a post by techguy:

Stale sessions would occur no matter when the load balancing was done, due to a BT issue.

Yes, thanks for stating the obvious (seriously, I KNOW this)

The issue isn't the problem Zen can't control, so much as knowing it happens and choosing WHEN more carefully to minimise the real impact.

Other ISPs do something about this. See AAISP.

In reply to a post by mixt:

But, if the actual session becomes stale, the router can attempt reconnection again, and again, and again, for up to something like 20 or so minutes, before it then clears within the BT system, and then things return to normal. I suspect this is what you are talking about, right? Stale sessions within the BT network itself. We were always told that leaving the modem off would clear stale sessions after 20 mins.

Nothing changed there, still the same, although it STILL doesn't always clear it even then.

Plus, as I said before, that all lines came back at the same time tells me that the true issue was elsewhere (I've been told it was Stale Session but I don't agree frankly). I still vote Zen had some other undisclosed issue too, given they also lost phones, but nobody wants to mention it.

I agree, it's all a bit of a farce to say the least. I don't think I've yet to experience a stale session (have they resolved them on 21CN? Is it still mostly a 20CN problem?),

No, still the same old.

I guess other off the shelf routers aren't as smart as this,

It's not a matter of being smart is it - although we're veering off the original issue, BT shouldn't be giving these valid PPP sessions and IPs - they should just refuse the PPP session, but apparently it makes more sense (to them) to stop the reconnect attempts by simply giving a useless session instead.

BT is the lowest of the low, it is the broadband infrastructure for the masses. I do genuinely expect it to be below par (or for what of a better word, s**t) compared to other offerings from other providers (like LLU etc).

Except in coverage, where only BT services are available almost universally. Everyone else plays the only the most profitable game and doesn't play the "overall revenue/profitability" game.

with 20CN being an even worse deal!

Actually I'll have 20CN back if you don't mind. It works, it almost always worked, and if it did go wrong, it was relatively easy to sort (and ISPs had a bit more control). Under 21CN it often breaks, ISPs get forced into situations where they cannot have as much redundancy against relatively common issues and we all suffer. All to have supposedly better speed.

In reply to a post by techguy:

While ISPs can and do hassle BT over individual customer issues I don't think they have the influence on BT to change their business processes or network unless they all band together and threaten to switch to a different supplier, this cannot happen until LLU becomes as ubiquitous as BT so for the moment BT can adopt a take it or leave attitude because no ISP can really afford to exclude customers on BT only exchanges.

I think ISPs could do a lot more, but the problem is that everyone went for a rush to the bottom (for cost to consumer) which now means that there is sod all margin and everyone plays the frankly nonsensical card of "ah well it is cheap and you need a leased line" thing.

If we were all still paying more per month, the overall pool of money would be better and more redundancy and such could have been afforded. The desire for paying sod all has taken away the sensible margins.

In reply to a post by therioman:

given they also lost phones, but nobody wants to mention it.

We didn't lose 'phones. All lines were busy due to the volume of customers calling about the problems being experienced, hence customers hearing the engaged tone when they attempted to reach us. Unfortunately that was unavoidable as customers were attempting to get through on multiple different numbers and teams.

regards,
Phil.

Hi Phil,

Um, no you did lose your phones, your status said so.

And I certainly couldn't even get engaged (otherwise I could have left it redialling), the numbers were NU.

Can you point me to the status message please?

I can only find this one which states callers were hearing the engaged tone and this was due to the volume of calls. Initially it was investigated as a possible fault (first note) but the second states it was due to volume, rather than a fault.

Calls were continuing to enter our queues throughout the issues.

I don't know why an engaged tone wouldn't be heard though.

ta,
Phil.