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[boost]

My VPs have been checked:

Right. There are 8 VPs I can see at your exchange from the report on the 4th Feb.

5 AMBER, 1 GREEN and 2 BLUE.

You're on the GREEN one, so in the date range used to compile the report there was no capacity issues.

I'm going to ask someone more faulty than me to have a look and see what they suggest.

Chris Parr
Plusnet Customer Relations Team

1 month old results mean nothing. Where does this elusive VP spreadsheet exist? What time of day are these VPs polled? etc etc

[tommy45]

Asking mr kennard at AAISP  may yield the info , as i doubt that you would get that from the likes of PN support. BTW you got similar results to me ,I'm on a green VP for what it's worth, thing is though with FTTC i thought it was the SVLAN status that was relevant  and not the Exchange VP's?

[kitz]

As a quick of a post as I can, because its very late... long days and also having to do lots of backend site stuff when I do get home:(...  so Im just going to blurb.


@boost - Theres an explanation and more information on such things as MSILs, APs etc on this page
http://www.kitz.co.uk/adsl/wbc_wbmc.htm

The main Core network is highly unlikely to be congested..ever. Would take a real catatrophic problem to see issues there.  Its highly resiliant and the way its meshed means that all major routes could be re-routed.   
It's unlikely to see congestion on any of the core nodes (think of this as entry point to the core), although this also could become a problem in a major outage (Say for eg when there was the Manchester fire near to / at the RAS many years ago).

Usual points of congestion are either the VP (for 20CN) or SVLAN (for FTTC) OR the ISP Host links (WBMC/IPsC).

OR Another point of congestion could be the MSILs/APs, but since PN is supposedly WBMC - Shared, then its BTw's responsibililty to maintain sufficient bandwidth on the WBC Interconnects. Ive no idea how BTw monitor these and what their proceedure is for upgrading them.


Re the SVLANs - Im not 100% certain on these.

CVLAN is the customer tag (inner), whilst SVLAN is the Service tag (outer).   I think the SVLAN is basically kind of the same as the old VPs and the amount of bandwidth available on that particular tunnel's 'backhaul', ie between the DSLAM and the RAS.

The new MSE bRAS may change things somewhat, because now many of the bRAS are closer to the dslam than they used to be.
It is possible to change SVLANs with much persausion (ie like BT would change you to a different VP if you moaned enough).  AFAIK you cant change your CVLAN, but you can (and will be) be grouped with other CVLANs in to an SVLAN.  There's 2 distinct different types of SVLANs 1)Copper-21CN 2)Fibre- FTTC.  Whatever way, I'm pretty sure that the SVLAN is the backhaul to the bRAS. 

Im unsure on FTTC if its from the DSLAM to RAS, or perhaps because of the fact DSLAM is BTor, then its possible it could be from the OLT to the bRAS.  Thinking about it further probably most likely to be OLT because this is the point where GEA is handed over... and in which case we also have a possible BT Openreach congestion point between the dslam and the OLT. 


Only your ISP or BTw has access to which SVLAN you are on.   The SVLANS are constantly monitored to make sure they dont run hot and are supposed to be upgraded whenever they reach a certain threshold.   The SVLAN status reports are updated twice weekly, but you need to know which SVLAN youre on to be able to check the reports.

[boost]

kitz: Interesting about the BTW managed interconnects. That might make a bit more sense with regard to people harping on about SVLAN issues.

jelv: You're wiltshire based? I wonder if Sheffield appears in your routing?

[jelv]

I know I go through Reading - just done a gateway hop and this is in the router log:

Code: [Select]

<132> Mar 13 09:59:27 PPP link down (Internet) [80.229.*.*]
 
<38> Mar 13 09:59:42 PPP CHAP Receive challenge from rhost ERX18.Reading (Internet)
<38> Mar 13 09:59:43 PPP CHAP Receive challenge from rhost PCL-AG05 (Internet)
<38> Mar 13 09:59:43 PPP CHAP Receive success (Internet)
<132> Mar 13 09:59:43 PPP link up (Internet) [80.229.*.*]

[boost]

I know I go through Reading - just done a gateway hop and this is in the router log:

Code: [Select]

<132> Mar 13 09:59:27 PPP link down (Internet) [80.229.7.240]
 
<38> Mar 13 09:59:42 PPP CHAP Receive challenge from rhost ERX18.Reading (Internet)
<38> Mar 13 09:59:43 PPP CHAP Receive challenge from rhost PCL-AG05 (Internet)
<38> Mar 13 09:59:43 PPP CHAP Receive success (Internet)
<132> Mar 13 09:59:43 PPP link up (Internet) [80.229.*.*]

You, Sir, are on the ball!

What does a trace route to bbc look like out of interest?

[boost]

[jelv]

Plusnet have been using IP Stream Connect for 20CN for a long time.

[boost]

Good to know

Max Premium still has a preferential weighting over WBC; AF31/AF21/AF11 I think so in the case of actual congestion, you are one of the few that should truly benefit.
Although I do seem to remember there being something about the CP having to buy special bandwidth for the Premium users? Can't remember now, will try and find it again.

[guest]

IIRC Plusnet's external (paid) routing is exceptionally limited? ISTR its basically BT public internet service & that's it.

So basically most traffic (60% +)  to/from Plusnet goes via AS2856 (BT public internet service - http://bgp.he.net/AS2856#_asinfo ) and then to AS5400 (BT plc - http://bgp.he.net/AS5400#_asinfo )

Also IIRC Plusnet only have L3 peering with them on AS2856 which caused significant issues last year when the BGP routing table exceeded 512k entries and lots of L3 kit fell over in a heap.

Frankly its pretty goddamn awful connectivity & that's where Plusnet save the pennies IMHO. Were it me I think I'd be looking at the interfaces between AS6871 (Plusnet) and AS2856 (BT Public Internet Service)...

Edit - There are differences in routing between IPv4 & IPv6 traffic from what I can see. If anyone can do a speedtest with both protocols (one after the other) from Plusnet then it'd be interesting to see if there is a difference.....

[Chrysalis]

ipv6 seems to exclusively use one provider trying to remember who they are but forgot the name, the traceroute entries have no rdns.

I agree the lack of transit diversity is an issue, they seem to have the usual peering to things like youtube, netflix, bbc etc.  But when is no peering its nearly always level3.

root@TomatoAC66:/tmp/home/root# traceroute6 google.com
traceroute to google.com (2a00:1450:400b:c02::8a), 30 hops max, 16 byte packets
 1  2a02:16c8:0:1::15 (2a02:16c8:0:1::15)  20.028 ms  39.774 ms  16.588 ms
 2  2a02:16c8:1:2::19 (2a02:16c8:1:2::19)  15.415 ms  15.382 ms  15.430 ms
 3  2a02:16c8::d (2a02:16c8::d)  15.371 ms  15.382 ms  15.017 ms
 4  2a02:16c8:1:2::8 (2a02:16c8:1:2::8)  15.795 ms  15.383 ms  15.805 ms
 5  2001:4860:1:1:0:1ad7:: (2001:4860:1:1:0:1ad7::)  15.818 ms  15.436 ms  15.770 ms
 6  2001:4860::1:0:15f (2001:4860::1:0:15f)  16.207 ms  15.775 ms  15.810 ms
 7  2001:4860::8:0:5bb9 (2001:4860::8:0:5bb9)  15.404 ms  15.394 ms  15.471 ms
 8  2001:4860::1:0:70c5 (2001:4860::1:0:70c5)  24.552 ms  24.225 ms  24.983 ms
 9  2001:4860::2:0:3de7 (2001:4860::2:0:3de7)  25.395 ms  25.379 ms  24.593 ms
10  *  *  *
11  de-in-x8a.1e100.net (2a00:1450:400b:c02::8a)  24.353 ms  24.847 ms  25.026 ms

I think I just remembered, might be hurricane electric.

[tommy45]

In that trace it would appear that Plusnet peers direct with Google,Well according to the reverse look up of the IPV6 , IPV4 appear to be the same routing to google.com  they would appear to of dropped the use of Level 3 peering by a lot recently , replaced by  BT peering now  , as if this will be a permanent thing is anyone's guess

[kitz]

Don't PN peer with TBB..  or at least they used to.   
In which case then there shouldnt be any external transit problems when doing speedtests with TBB

[kitz]

I'm making the assumption that PN is L2TP passthrough

Yep afaik practically all of the BTw based ISPs (aside from BTr) use l2tp.

A quick reminder of which bit of the network we're talking about - BT BRAS to CP BRAS:

Only BT has bRAS.    The bit you highlighted in red (aside from the MSILs) is mostly CORE transit.
SVLAN & VP is the bit before the bRAS. On 20CN, the VPs are definitely MSAN to BRAS location ie backhaul.

[tommy45]

Don't PN peer with TBB..  or at least they used to.   
In which case then there shouldnt be any external transit problems when doing speedtests with TBB

they peer via linx-gw1.thn.ncuk.net