I am glad you said its unlikely to be the same gateway
Actually come a new day and Im absolutely certain its not the same gateway. Do a google on
central10 and plusnet and you will see from the tracert results that come up, that just about every gateway has its own 'central10'. Because the gateways are scattered in various locations, then its physically impossible for it to be one and the same. Making it look like my assumption last night that its just a naming convention for the endpoints at
each gateway.
I think I remember reading somewhere tho that the 655mbit centrals are history with 21CN, now its gigabit. 10xgige etc
Yes thats correct.. theyre long gone - When I wrote
this in 2009 the host links & MSILs were 1Gb or 10Gb, with BT looking at providing 100Gb links at a future date.
Its pretty damn obvious that the bng gateways are supporting larger host links than the ag gateways. Remember though that the ISP doesnt have to light the full link and they just pay for the portion that they need. Theres a lot of public confusion over the MSILs, which is why I specifically added a section on
how the MSILs, APs and EPs slot togetherI would guess some of the pipes feeding the (older) gateways may be 655mbit but they would be for 20CN users only like Jelv.
Nope - all of the 155's & 622's are long gone.. they are using
IPStream Connect (IPsC) for all the 20CN exchanges and steering those Gb host links to specific gateways.
The BNG's have a load of around 45-53k which I think is lower than at start of week.
REALLY!! you know I think your right, I hadnt noticed todays reduction - werent at least 2 of them showing a max at circa 66k yesterday? Hmmmm.. earlier this morning, I made a post on the Plusnet forums and I really wish Id spotted that reduction before making that post. Why the heck would Plusnet reduce the subscriber session limits.. unless it really is what I theorised in that very same post that the gateways really do fall over when they reach a certain maximum figure of sessions.The important thing to remember here is that subscriber sessions and bandwidth arent the same thing.
I did think it was pretty weird this morning that the surplus sessions were only 9k. Yet I had thought the other day when I looked that there seemed to be plenty especially on the 2 bngs that had new endpoints lit last week. I hadnt twigged that theyd reduced the max sessions.. yet the bandwidth will still be there. I honestly cant think of any other reason why they would reduce this figure unless it was a physical limitation of the gateway not being able to cope with a certain number of simultaneous sessions.Edit - the max figure was a red herring, based on the way Id read the graph
It does seem the BNG's are lower weighted now I only needed 4 attempts to get a non BNG gateway whilst before the crash I needed over 30.
I suspect that may more have to do with
session steering. Last week for sure they were steering towards the new endpoints... meaning they were setting a preference which pipe a user attempted to connect to first. They were pushing the BNGs as a preference for [fttc] users which will be why you had a harder time to get a non BNG gateway. If you look at todays graph everything seems nicely balanced, so they will have turned off the preference steering. Obviously the IPsC steering will still be in place though.