Annex M on Market 1 exchange

Hi all,

BT Wholesale's checker says ADSL2+ is now available from my local exchange (some 4 months ahead of the RFS date on Sam Knows - well done BT). The exchange (Kilmacolm - WSKIM) is market 1 with no providers other than BT and no cable either.

My current connection is 8128/832k unlimited via Talk Talk Business (my old ISP, F2S was merged with TTB, I'm not actually a business customer). Not at all happy with TTB so I'm looking to change to another provider as part of upgrading to ADSL2+.

I regularly have to send hefty files so I'm looking to get Annex M to maximise upload speed. But finding an ISP that will provide it without requiring an expensive business package is proving to be a chore. Need a download cap of no less than 30GB/month also.

Any pointers to an ISP that will do this without wanting an arm and a leg in return would be very welcome!

http://www.plus.net/business/broadband/

Option 2 seems ok.

If you have 21CN active on your exchange then Annex M should not be a problem, most providers should be able to offer it (as long as they know what they are doing) to give an example, we can add annex M to any of our BT Based products for an extra £10.20 per month (inc VAT)

Welcome to the forums .

We need to see the line stats from your router if you can find and post them. Those will tell us fairly accurately what Annex A speeds you could expect from ADSL2+, and those in turn will tell us whether Annex M will be worth having.

In general, with an Annex A downstream connection of 16Mbps or less you lose about 2.5Mbps downstream by going to Annex M, with no significant upstream increase above the 1.1 or 1.2Mbps you will get on Annex A. As the Annex A downstream rises towards 20Mbps the loss on Annex M is less and the upstream increase is greater.

The short explanation is that Annex M pinches the lower downstream frequencies to add to the upstream ones, and at high attenuations there is insufficient capacity in the additional (ADSL2+) downstream ones to compensate for the loss, and the pinched ones have a similar effect when used for upstream - they may hardly contribute.

Edited by RobertoS (Fri 08-Jun-12 18:16:52)

Considering the costs that Annex M incur, versus the gains (which are different for each connection), is line bonding an option?

Thanks for the comments everyone, much appreciated.

RobertoS, the line is nice and short so hopefully shouldn't be an issue. Router stats are:

ADSL Link Downstream Upstream
Connection Speed 8128 kbps 832 kbps
Line Attenuation 9.0 db 6.0 db
Noise Margin 8.6 db 11.0 db

I'm leaning toward Vivaciti's Home 100 package at the moment, will probably go for that if nothing better pops up by time I can squeeze a MAC code out of TalkTalk.

You would benefit greatly from Annex M as you line is capable of the max 24 Meg Downstream on ADSL2+.

Agreed. Downstream won't be affected, and as near as dammit the full 2.5Mbps upstream will be there.

Bear in mind that in Market 1, the cost of option 2 is £23/ month. I'm not sure if Annex M makes it cost any more.

To the OP: You need minimum 30GB, but how much of that usage is required when you're sat at the computer, and how much could happen, say, overnight? I certainly use a fair bit each month but the vast majority is transferred overnight.

When I put my number in Option 2 actually comes back as £26pm or £36pm with Annex M, which seems like fairly poor value.

My daytime use is hovering around 13GB/pm right now, I already queue large uploads and downloads overnight to leave the connection free in the evening (for gaming mostly). There doesn't seem to be much money to saved going for an off-peak unmetered package unless its one where the peak allowance is something silly like 3GB.

The switch from TTB and ADSL Max to Viviaciti and ADSL2+ has gone through. Yay! Well, actually just half a yay.

I held off going for Annex M to see what kind of speeds plain ADSL2+ would give me first. And these are the new router stats:

ADSL Link Downstream Upstream
Connection Speed 22886 kbps 888 kbps
Line Attenuation 10.0 db 3.5 db
Noise Margin 4.9 db 9.5 db

I'm a bit underwhelmed, to be honest. Downstream is fine, but upstream seems far too low. I expected rather more than an extra 56kbps upstream, having seen lines much longer than mine doing 1Mbit+. The router (DGN2000) is connected directly to the test socket.

Is this likely to be a router issue? Happy enough to buy a new one if it'll improve upload speed. Or should I prod Viviaciti about it?

In reply to a post by DrBC:

Connection Speed 22886 kbps 888 kbps

That 888 K up is a peculiarity of BTw's DLM which caps it at that when on Interleaved. Dunno how Annex M would affect it but as it's designed for high upload it must uncap it.

If you can get full router stats via TELNET (see http://www.kitz.co.uk/routers/netgeardg834_interleav... ) look out for a line like:

D: n 1

n > 1 Interleaved; n = 1 Fast Path.

Or ask ISP to turn Interleaving off and you should get about 1.2 Meg up.

Ahh, that does make things clearer. Thanks.

The router reports 'D: 160 8'. Ran DMT and it confirmed interleaving is on, both upstream and downstream.

I hope you haven't done lots of dis/reconnections.

Not even one so far. Router synced up after the changeover and that's it.

Very nice stats

once annex m is active i would suprised not to see around 2500 upload.

I would very much hope so, but things tend not to be quite that straight-forward!

Opened a ticket with Vivaciti about the interleaving, which they promptly disabled. Router is now syncing at 1027Kbps upstream and downstream has nudged upward too:

ADSL Link Downstream Upstream
Connection Speed 23245 kbps 1027 kbps
Line Attenuation 11.0 db 3.6 db
Noise Margin 5.8 db 6.7 db

But 1MBit is still rather less than I expected from this line, which makes be wonder if Annex M would actually deliver 2Mbit+ speed. And on the subject of Annex M, Vivaciti have informed me that it is not available with the package I'm on and I'd have to switch to a peak-time metered package in order to get it. Ho-hum.

We can do Annex M on your package, but it's quite expensive to sign up to or migrate to so we do not offer it, but we can do it is you want, I think from memory the fee is £75.00 + VAT just to connect to it.