VOIP and BT Infinity 2 traffic shaping

Hi,

I am looking to sign up to the Infinity 2 plan but wanted to know if people have had experience with using VOIP on these plans. My main concern is that I don't know how the traffic shaping works and don't want the shaping to affect the call quality/latency. Previously I was on a Virgin adsl plan and there was always a bit of lag during calls. I am currently with Zen and the call quality is pretty good. Any comments from VOIP users would be much appreciated.

Thanks

Infinity should have plenty of bandwidth to be able to support VOIP with ease, however using the default modem and router, they seem to apply shaping almost randomly using the TR069 interface.

It is possible to replace the modem or even load hacked firmware, in order to close off this potential shaping vector, but as I say it appears to be random and may not affect you anyway.

Not come across the use of the remote config TR069 interface for traffic management/shaping usually this is the job of much more expensive hardware in the central network.

Where is the use of tr069 for throttling documented?

You should ask BT about that

I will do, just curious to find out what the Internet people have to say about it first.

TR-069 is normally used for remote configuration of hardware, i.e. you plug in router and DSLAM sees it and configures router and can do remote firmware upgrades etc via the XML SOAP interface.

There is of course the use of reserved bandwidth that BT Vision has had with various versions of hardware over the years, which I presume is still in place. But not sure how that pertains to a VoIP enquiry and BT Infinity 2 which should be running a LOT LOT faster than any BT Vision/YouView IPTV content.

One of the problems BT would face doing shaping using expensive hardware in the central network is that they use centralplus which is straight onto the internet, so no opportunity to shape there.

Incorrect, Central Plus (which is not really used now) had the perfect setup for this, in that there was 16 to 22 nodes where servers such as the Ellacoya's (which they had and used and probably still are) could be place, and thus reduce the amount of Internet bandwidth that had to be purchased.

You really need to speak to BT, I'm sure they would be surprised to learn Centralplus is not really used now.

Central Plus is the IPStream based system, and thus only relevant in the 15% or so where the WBC network is not available, and even then IPStream Connect product lets them handle the old exchanges via the newer WBC network

I use VOIP on a BT Infinity business connection and it barely dents the available bandwidth even when using two lines. Even if you were dramatically shaped as VOIP is prioritised you will not see any difference in quality or latency - The latency is not noticeable - I do a lot of work on remote satellite comms and am very aware of latency be it just a fraction of a second or two to three seconds.

I'd better go read SIN 472 then http://www.sinet.bt.com/472v2p0.pdf

In reply to a post by musicaddict:

wanted to know if people have had experience with using VOIP on these plans.

I've just closed my SIPgate account but was using it through my Draytek 2820Vn router with a basic telephone attached. Calling friends in the US it was fine, no issues.

Yes I replaced the BTHomehub with the Draytek, WAN2 port connected to the Openreach VDSL modem.

We've used quite a bit of Skype and a little VoipStunt. Plenty of issues with Skype calls to Malai, but I don't think that was Infinity's fault! Otherwise, no problems. That was all with the regular HomeHub (3B), and on the stadard unlimited home Infinity plan.

Edited by StephenTodd (Wed 12-Dec-12 10:31:45)

In reply to a post by MHC:

I use VOIP on a BT Infinity business connection and it barely dents the available bandwidth even when using two lines. Even if you were dramatically shaped as VOIP is prioritised you will not see any difference in quality or latency - The latency is not noticeable - I do a lot of work on remote satellite comms and am very aware of latency be it just a fraction of a second or two to three seconds.

Are you on the 100gig business plan or the unlimited. Do they shape/ traffic manage on the business plans?

Edited by musicaddict (Wed 12-Dec-12 10:02:12)

Currently on an old unlimited business plan which is changing next week to the new unlimited plan.

There is no traffic shaping as far as I have experienced on the business services. There is always traffic management on any service - for example ensuring VOIP services have a higher priority.

So your experience on the business plan with no shaping will be very different to the standard residential plans. I see your point about the traffic management and that is fine. My whole concern is that the shaping that happens on the residential plans might add latency or interfere with the voip call in some way.

In reply to a post by jchamier:

Yes I replaced the BTHomehub with the Draytek, WAN2 port connected to the Openreach VDSL modem.

Did you have issues with the BTHomehub or just wanted a better router?

My whole concern is that the shaping that happens on the residential plans might add latency or interfere with the voip call in some way. Just edited my post above, to comment that my VOIP has been working fine on the standard Infinity home plan.

My latency is not very good (29ms to bbc), partly because of interleaving and partly because of silly BT routing. However, very little jitter and no observed bad effect on Voip.

Edited by StephenTodd (Wed 12-Dec-12 10:35:35)

I have tried running some very large downloads - GigaBytes and at the same time using the VOIP connection. I notice no change in the quality for maybe 99.99% of te time and no additional lag/delay. Yes a packet may get lost/delayed which could result in a small error but very small.#

looking at the various stats for Jitter, Loss, One-way delay, Round trip time shows nothing significantly different from a call with no traffic running. So, even if you are managed/capped in any way, I would doubt that there would be any perceptible problems.

The whole point of the traffic shaping, or at least a major part of it, is to ensure that latency for gaming and VOIP is maintained at a decent level, by restricting torrents and suchlike loads on the network.

The whole point of traffic shaping is to allow BT Vision to work given that BT have made a huge investment in Premier League football for next season. I think congestion tends to happen at the cab which is why BT employ shaping using TR069 - at a very granular level.

The advantage of a BT Business connection is that they guarantee a certain throughput, maybe 15 or even 30 Mbps. No such guarantee applies to BT Residential however, and everything is on a Best Effort basis including VOIP - not so comforting when Man U are playing Arsenal.

So still waiting on you explaining how TR-069 is doing the traffic shaping?

BT Vision is more about QoS controls, than the traffic management that is used for P2P throttling.

I think you are mixing and matching the BT Wholesale Best Efforts and Assured QoS options with what Retail do to traffic themselves.

http://www1.btwebworld.com/sinet/483v1p1.pdf

Remember that the Assured session booking actually costs money too.

In reply to a post by MrSaffron:

So still waiting on you explaining how TR-069 is doing the traffic shaping?

I've already suggested you ask BT. Did you?

Not yet because its the sort of thing I need to discuss offline with them, as many more questions to be asked.

Why don't you just explain then everyone can learn.

The FON set aside will require changes to the router configuration and as such I expect these parameters for the upstream QoS control to be sent across when FON channel is enabled, but the day to day traffic management relating to P2P and VoIP are not going to use TR-069 because the obvious way around the restrictions would be for a customer to use a router other than the HomeHub.

All I can say is what happened to my connection and the steps I took to fix it. The bottom line is that I noticed TR069 entries on my router log corresponding to when my speed was reduced. I stealthed the open port on the modem and I haven't had a slow down since. I asked BT but received no response.

So you are saying that you now get full speed all the time on all protocols by simply stealthing the port used for TR-069?

Or was this an across the board type speed drop?

Certainly on all the protocols I use. I don't use P2P however so I don't know about that one. I mention P2P as that's the only one BT admit to throttling.

Edited by BatBoy (Wed 12-Dec-12 15:15:02)

In reply to a post by musicaddict:

Did you have issues with the BTHomehub or just wanted a better router?

I already had the 2820Vn and the HomeHub is a very very simple router. Functional but nothing special.

There's no reason to go for the business plans over the domestic, we have business ADSL at work as work needs them to bill under the big BT contract, and so we can't get the domestic tarrif level - we have no need for the "business add ons" that BT are selling. Not noticed any difference in the IP connection apart from my domestic Infinity is capable of higher speeds.

In reply to a post by BatBoy:

All I can say is what happened to my connection and the steps I took to fix it. The bottom line is that I noticed TR069 entries on my router log corresponding to when my speed was reduced. I stealthed the open port on the modem and I haven't had a slow down since. I asked BT but received no response.

I wonder if that's an artefact of using the Huawei as a router - rather than the Huawei passing PPPoE through itself from the external router. Could be a Huawei firmware issue perhaps.

In reply to a post by jchamier:

... we have no need for the "business add ons" that BT are selling.

What about the faster fault fixing?

In reply to a post by RobertoS:

In reply to a post by jchamier:

... we have no need for the "business add ons" that BT are selling.

What about the faster fault fixing?

Nope, we don't need that - if its out for 3 days or so we are ok. They won't do a real service level on any of the products.

(This is for a test/dev system, not our corporate internet).

In reply to a post by jchamier:

Not noticed any difference in the IP connection apart from my domestic Infinity is capable of higher speeds.

That is due to the line, not the service.

In reply to a post by jchamier:

In reply to a post by BatBoy:

All I can say is what happened to my connection and the steps I took to fix it. The bottom line is that I noticed TR069 entries on my router log corresponding to when my speed was reduced. I stealthed the open port on the modem and I haven't had a slow down since. I asked BT but received no response.

I wonder if that's an artefact of using the Huawei as a router - rather than the Huawei passing PPPoE through itself from the external router. Could be a Huawei firmware issue perhaps.

Unlikely, as that was part of the solution rather than the problem.