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We operate in an office building very close to the Sydney CBD and as a result our office currently uses a direct fibre connection at the cost of $1000/month for 2Mb/2Mb (yes, I realise how stupidly expensive that is, but that's how much fibre costs in Australia) and a very very low contention ratio (like, almost 1:1).

The connection was sold to management with little/no input from the IT team, based on the fact that "oohh, it has almost 1:1 contention, we're not going to be sharing our bandwidth with anyone" and admittedly yes, it's been rock solid, but c'mon - it's only 2mb.

They've finally come to the realisation that $12,000/year is too much to be paying for a 2mb link, and we're investigating business-grade ADSL2+ connections, as other people in our building achieve sync speeds of over 20Mb.

What are people's experiences with ADSL2+ in an office scenario (I've only ever used it at home, with suitable experience)? We have a site-to-site VPN to a datacenter and do a lot of heavy file transfers over the VPN but other than that it's a pretty normal office. We currently lease a few dozen lines for a phone system which we're hoping to move to VoIP in the next 12 months.

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With a theorethetical maximum upload speed of 1.4Mbit (and I doubt they're going to give you that) I would be wary of this. You need synchronous, especially if the disparity is 20 to 1, with VOIP and other bandwidth intensive operations.

Having a home connection with such a disparity might be fine - you spend 95% of your time downloading, but with a business you upload just as much as you download. It appears that SHDSL is coming your way... maybe it would pay to wait a short while. $700 a month for 5Mbit synchronous DSL (5Mbit up/down) seems a much better deal than you have now

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Ooh, SHDSL is a term I havent heard before, I'll need to look into it, thanks! – Mark Henderson Jul 7 '09 at 2:25
You definitely need to look into a synchronous solution. I'd say SDSL, but that's just 2mbit up/down and you're already not happy with that (although it would be cheaper than your fiber). SHDSL for the win – Izzy Jul 7 '09 at 2:33
Hmm, for $1000 Internode (who I use at home) offer SHDSL 10Mb/50Gb. Given apples:apples that makes fibre seem even more rediculously over-priced. – Mark Henderson Jul 7 '09 at 2:41
You think you'll go for SHDSL when it's available then? Think you could get them to stretch to the one of the unlimited plans? – Izzy Jul 7 '09 at 23:37
Interestingly, 2 years after posting this, we did move from a bonded ADSL connection to a 10Mb SHDSL link. It's like you could see into the future! – Mark Henderson Aug 31 '11 at 11:47

My small office group is located in the Brisbane CBD.

We originally had OptusNet cable (when I arrived), and were paying a premium for a simple cable connection.

When ADSL2+ was rolled out I started a proposal followed by a massive cut over plan to an Internode ADSL2+ connection.

In the end we now have a SOHO plan with 25GB, look below for speeds as I just ran a test.

Download increase was fantastic to have in the office. However our upload is not much better but since we are small it dosnt matter that much. It also comes with all the bells and whistles of the unmetered services from Internode. (Which is a lot)

ADSL2+ is a little bit of a gamble because it heavily relies on your distance to the exchange. Best way to figure this out is to use Google Earth and measure the distance (but you must remember that it is cable distance not building distance). Work out the signal attenuation and match it up to see what you might get. (line attenuation is also a factor).

With upload speeds you might be a little starved. I am not fully knowledgeable on the actual max upload speeds of ADSL2+ but this discussion seems to estimate it at 1024 =~ 128KB/sec. This might not be suitable for your situation but I think you should be able to get a better deal than $12,000/year now days...

See Whirlpool Sync Speeds for more information. You might even find people who have submitted their own sync speeds with you exchange that are nearby to you.

Not to only praise Internode I recently upgraded my home ADSL to iiNet ADSL2+ with Voip and it has been a complete blessing. In my opinion if you go with iiNet or Internode you have picked a winner.

Also I just located the old Internode Sync Speeds graph (a little old but it is a nice graph).

Hope this info helps, it isn't easy figuring these things out, (especially with Australian Internet >_< ).

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We are within 500m of the exchange, so we should get good sync, and with M-Annex we should get 2mb up or thereabouts... thanks for the info! – Mark Henderson Jul 7 '09 at 2:22
Do remember that latency will generally be higher with DSL than Fibre - that may or may not be important to you. At my previous employer, we (company of ~20) used DSL quite happily, had ~15Mbit/1.5Mbit or so IIRC. – mibus Jul 7 '09 at 2:39

I would be careful with ADSL2+ in conjunction with VOIP. We had this setup at two small offices; one of them had issues, the other one didn't.

Consider having bonded T1's or fiber for the VOIP, and use ADSL2+ for other traffic. I would also double-check the ADSL2+ SLA to make sure that it is truly business grade.

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We just have a second ADSL1 connection for VOIP - 1mbps upload suffices. – TRS-80 Jul 7 '09 at 5:23

ADSL(2) is poor at uploading. In particular as soon as you saturate the upload link the latency goes through the roof. If you don't do much uploading maybe that's not a problem, but wherever we've had sites that have to send out lots of data we've had to switch to SDSL or wireless (wireless Internet is becoming quite common in the UK).

We've had lots of pain running VOIP over ADSL unless the VOIP has an ADSL line of it's own i.e. no other traffic on that line. I suspect this is because of the poor upload performance. When someone sends out a large e-mail the resulting high latency on the ADSL line kills the VOIP connections.


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There are other alternatives like the trunked SHDSL known as "ethernet in the first/last mile".


Another thing to look at is IP bandwidth in Australia retails ~$300/Mbit (you can get a bit below $200, but you need to be in the 100+ range) so the fibre isn't that overpriced.

I have a quote for a 10Mbit service to an inner-city Melbourne address for ~$3500/month (High quote as fibre is getting dug for this)

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In my experience, ADSL2+ works well for light loads. My experiences come from SOHO environments where one VoIP line has coexisted with up to five workstations over adsl2+ and medium size business over 8/8 shdsl with heavy restrictions on allowed traffic.

The key to getting away with ADSL2+ is high quality QOS. I'd recommend l7-shaper as a cheap and efficient option and Gentoo as the base OS for the shaper, because gentoo has the required patches in the infrastructure. You can of course buy a good shaper if you have the budget.

Bonding ADSL2+ connections is a completely different scenario, but I'd go for fibre or VDSL2 if available.

In any case I'd recommend a good shaper, commercial or not, to prioritize connections depending on content instead of port-based shapers.

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