Disconnects

[mirdragon]

Not sure how much access the ISP's have to the network and dslams, but I know with BT they can tell if you are authenicating at the dslam or not - as when I had an issue they confirmed we weren't authenicating past the dslams and that everyone on the one we were attached too were affected. it turned out a number of ports were affected

[jody-ASK4]

We have no visibility of the access network, it's managed by Thales. Customer's circuits are just presented to the ISPs over an Ethernet interconnect so there's no PPP auth done in the DRL side of the network, PPPoE is wholly implemented by the ISPs. The DRL network is there to just send and receive Ethernet frames between the ISP and their subscribers.

What happens with these drop outs is that the Ethernet frames stop getting delivered between the ISP and the affected subscriber(s) in at least one direction for what appears to be a small and random amount of time.

[alexatkin]

Which is basically what we thought. The question of course is WHY the traffic suddenly stalls.

Is this a problem with dropped packets on the VDSL link itself, or even more worrying (and I fear likely) that the packets are being dropped somewhere along the Digital Region backbone on its way to the ISP?

My connection may be the former, because it gets better if I force a resync, yet clearly the problem is not bad enough to cause the sync to drop on its own.

On the other hand, maybe forcing a resync fixes the problem temporarily for another reason - it forces to DSLAM/BRAS to re-establish its session?
As I do not know all the ins and outs of how it routes the traffic over the network (except it involves VLANs), there could be so many places things go wrong that forcing a reconnect might fix - with nothing at all to do with the relatively few errors I get over the VDSL link.

This is why I HATE how Thales do things. If they were willing (or able) to make fine adjustments to the line profile, we could at least eliminate the VDSL link as the cause. We could know for sure I suppose if I were to downgrade back to 40Mbit and see if the problem remains, but thankfully the problem is not bad enough to consider doing that yet.

I certainly do not think people having this in its more severe form are having VDSL problems though, as @mirdragon DID have the profile changed several times to ensure the VDSL link was not the issue.

[mirdragon]

A lot of things were changed on my line, some of it I wasn't privy to - but since moving back to BT I've had a more stable connection

My line has now been up for over 32 days after I was messing with wireless settings and moving access points - see attachment - I think the maximum time i was connected with Ripwire was 10 days.

The longest with BT is 42 days, not sure if this is because they reset things every so often.

I'm still getting good speeds and now on the fully unthrottled system - see the p2ptest

my last speedtest

[john22rob]

i assume the DR network is totally different to any other network. Firstly i have noticed i can use my username and password at a different address, i was surprised. this isnt possible with any other means of internet? this maybe going off topic abit but just with ask4 saying the DR is just an ethernet connection as such. worryingly doesnt this mean people could share a subscription? steal and use at a different location etc

[bgnx]

The above is also possible with some ADSL providers. As long as you are using the PPP details on another connection that is being provided by that same ISP, you'll authenticate and get online.

I don't think this is possible on most of the big ISPs but it has worked for me on a few that I have tried.

You wouldn't really be able to share a connection though; first of all you'd have to physically be connected to the network, as in have paid to be connected to DR and be paying a subscription to continue to be connected to it. You'd also have to be on the same ISP otherwise you'd be in a different vlan and not be able to speak to the correct ISP's authentication server and as soon as you did authenticate, I'd imagine the other PPPoE session would drop?

[alexatkin]

This is what is confusing about VLANs, as we already know that all ISPs have the same VLAN at the modem end which was a huge surprise to me.

I can only guess that the VLAN we see on the modem is merely between the cabinet and your modem. The DSLAM/BRAS presumably then routes your specific line down the backbone VLAN relevant to your ISP.

[jody-ASK4]

(10-03-2013 01:21 AM)bgnx Wrote:  The above is also possible with some ADSL providers. As long as you are using the PPP details on another connection that is being provided by that same ISP, you'll authenticate and get online.

I don't think this is possible on most of the big ISPs but it has worked for me on a few that I have tried.

You wouldn't really be able to share a connection though; first of all you'd have to physically be connected to the network, as in have paid to be connected to DR and be paying a subscription to continue to be connected to it. You'd also have to be on the same ISP otherwise you'd be in a different vlan and not be able to speak to the correct ISP's authentication server and as soon as you did authenticate, I'd imagine the other PPPoE session would drop?

Whether the other session would drop or not depends on how the ISP has implemented their platform. Ours has a single PPP IP bound to each account so you'd get a duplicate IP issue.

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(10-03-2013 10:49 PM)alexatkin Wrote:  This is what is confusing about VLANs, as we already know that all ISPs have the same VLAN at the modem end which was a huge surprise to me.

I can only guess that the VLAN we see on the modem is merely between the cabinet and your modem. The DSLAM/BRAS presumably then routes your specific line down the backbone VLAN relevant to your ISP.

The CVLAN is the same across (most) subscribers however users of different ISPs will have a different SVLAN which dictates which ISP their traffic will turn up at.