I guess it's donkeys old but still interesting:
The diagram is old, but newer than mine
here which was from back in the days when I was bang up to date with things like centrals and what equipment PN had. I lost track some time around 2009 mostly because I wasn't with PN and lost interest in keeping up to date with what they were doing... it was also a bit harder to get info because they were now owned by BT and most of my contacts had moved on.
I assume the following from the gateway names:
Yep - they've always used that type of naming convention.
PTW = Plusnet Telehouse West
PTN = Plusnet Telehouse North
I always thought that CL = City/Central London. iirc 'PCL' first started when they took over Metronets pipes circa '06. I cant recall for certain, but I think it originally may have been Telecity,
Central
London. Whatever way City Lifeline also fits nicely now.
Prior to that they also had PTH which originally was Telehouse East, later changed to PTE to match the others. PTH (PTE) was the terminating colo for their original centrals when they first started selling adsl.
AG and BNG are presumably two different types of router.
No, the second part (AG/BNG) isnt specific to the make & model of Edge Router.
'AG' simply denoted 'Aggregator' which was followed by the number at that particular location. These were Juniper ERX 1440s (x6) and iirc by about '09 they also had x8 what were at the time shiny new E320's. Going back even further in history, a couple of Redbacks were the original pth-ag1 & pth-ag2. To be more exact their full name as advertised by their manufacturers was Redback SMS 10000 Broadband Aggregator.
BNG = Broadband Network Gateway. Unsure exactly what model they are, but yes Juniper MX is the route they headed after ERX became EOL (end of life).
From a quick scan of the specs for all the MX models then it would have to be at least an MX960, but it could also be an MX2010/2020.
Depends on how how much they budget, what model was available at which date, and when they bought them. PN always used to go for top of the range capacity model when it came to their edge routing. Makes sense I suppose, they have a lot of customers so the larger models work out more economical in the long term as they can cope with more sessions and multiple endpoints. No point having to buy 2 of the cheaper models when you can save a bit of money by purchasing just one of the higher spec.
As regards to the ERX/E320's - Just because a product is EOL doesnt mean that the ISP will replace them. These are very expensive & sturdy bits of kit and have many replacement slot-in parts. Both the E320s and ERX1440's were top of the range in their time designed to last for years and still have plenty of life in them. Because they were top of the range kit in their time, then they will still happily cope with multiple endpoints and be supported by JunOS. I tried to cost up the price of an ERX many years ago and iirc you're easily looking in the region of £500,000. Not something an ISP is going to replace every few years and why there is a market for powerful second-hand edge routers. As an indication Zen have only just replaced their Redbacks (PN replaced theirs 8/9yrs ago).
my extrapolation is BNG = DPI
Procera as you say is into Deep Packet Inspection. This is a bit of a weird one. Arbor Networks aquired Ellacoya Networks, yet there's quite a lot of same staff at Procera who used to work at Ellacoya. Arbor doesnt seem to be into DPI and Procera quote themselves as being the only company that delivers 'Internet Intelligence'. Ellacoya used to be the most advanced and intelligent when it came to DPI.
Plusnet have for years (since 2006) used Ellacoyas for DPI on their E/ERX's and since Procera was recently awarded a major contract with BT for DPI then I would imagine that they are simply using Procera on the 2 new BNGs because you cant buy 'Ellacoyas' any more.
increased latency once load is greater than n
No - The whole idea of using Ellacoyas/Procera, is so that when things do get busy latency does not suffer.
The Ellacoyas are very intelligent, if the network is busy latency should not be affected at all, instead it will start to throttle back on other protocols such as p2p or nttp. Latency is usually given priority over all other protocols because its essential for gaming and VoIP. HTTP (web browsing) and web based speedtests would also not suffer, as http is usually given priority after latency affecting apps such as VOiP and gaming. You'd notice it on p2p for sure though. The intelligence part of DPI is that you cant fool them by changing ports and attempting to make p2p look like http... and why the name Ellacoya is hated by certain communities.
I'd much rather be on a busy network controlled by Ellacoyas than one without. When on Be* there was one episode when we were waiting for our exchange backhaul to be upgraded. Latency goes to pot without proper traffic shaping, http speeds go to pot.. but heck I could still max out nttp by opening 6 threads.
Hmm you have a point there.. it took PN ages to get the ellacoya configs right... I wonder if there could be something in the fact they are now using Procera its another new learning curve.. I dunno.
hmmm again.. I think if it was a config issue then again it would be all users on the BNGs and they'd be complaining about something other than latency and http.
the PN xconnects between PTN/PTW/PCL for any site specific transit.
It had actually crossed my mind the other day, but I soon discarded it because far more users would be complaining - ie all those connected at any PCL or at any PTW gateways would get rubbish speedtests at TBB (Linx @ THN), or out to the Internet via 'x' routing. It would be much easier to spot as it would become more site specific. You'd start seeing silly things like good TBB speeds but poor speedtest.net results and vice versa depending upon location of the gateway you are connected via and which transit/peer was at that location.
found this forum post:
lol it's no surprise that their naming convention is the same... because I know who that is
Gawd am I a mine of useless information or what.
I also just surprised myself that I can remember half this stuff, yet can't recall what I had for tea yesterday.