Hi,

I have a friend who runs a small charity and may need to move away from
the pabx they have been using, and I am researching other options for
them.

They need 4 handsets and 1 fax/modem line.

Would it be feasible to have a couple of dual terminal adaptors, or 4
VOIP phones plugged into a 10/100 switch along with their 4 computers,
and connect to the internet via adsl.  The concurrent "load"  both in
terms of web/email traffic and data and VOIP traffic would be light.

This would leave the "voice" bit of the ADSL to drive the Fax/Modem.

Most calls would be to uk landlines, so a serice provider would be
needed for the ip-pstn "conversion".

What bandwith would be required on the ADSL in order to get 4
simultaneous VOIP calls in addition to a little data? (This would
rarely happen, but has to be taken into account).

Budget as you might expect is extemely limited, but if the simplest
solution is just a little more expensive, it would be the one to go for
(esp if it means I could handle the install/config without having to
bring in external people).

What equipment/solutions/providers would people recommend?

TIA

Cheers

Chris

[ Post a follow-up to this message ]

You may want to take a look at www.voipfone.co.uk

or read the Virtual PBX section of the user manual here:

http://www.voipfone.co.uk/Voipfone_User_Manual_v1.0.pdf

There's a user forum to chat it though if you need to

http://www.voipfoneuserforum.com

I declare an interest :-)

colin, voipfone.

[ Post a follow-up to this message ]

cjd wrote:
> You may want to take a look at www.voipfone.co.uk
>
> or read the Virtual PBX section of the user manual here:
>
> http://www.voipfone.co.uk/Voipfone_User_Manual_v1.0.pdf
>
> There's a user forum to chat it though if you need to
>
> http://www.voipfoneuserforum.com
>
> I declare an interest :-)
>
> colin, voipfone.

Thanks for that Colin.  I declare an interest too (in as far as it
looks interesting :=))

I must say, VOIP is the first computer/network thing in a long time
that has gotten me excited!

What I couldn't find there was any recommendations as to what "speed"
ADSL line might be required for 4 simultaneous VOIP conversations.

Anyone any idea on this?

[ Post a follow-up to this message ]

A thread was started on that here:

http://www.voipfoneuserforum.com/viewtopic.php?t=104

It's 'how long is a piece of string' question finishing with 'it all
depends'.

The real world effect is very hard to predict from the theory which
would suggest that 4 users should work on a ordinary ADSL link (where
the upchannel of 256kbs is the bottleneck).

Luckily it's something that you can experiment with without making any
serious investment. In practise we have many 2-8 extension users on
ordinary ASDSL lines. As they grow they tend to get a dedicated ADSL
connection for VoIP then move to SDSL.

[ Post a follow-up to this message ]

cjd wrote:
> A thread was started on that here:
>
> http://www.voipfoneuserforum.com/viewtopic.php?t=104
>
> It's 'how long is a piece of string' question finishing with 'it all
> depends'.
>
> The real world effect is very hard to predict from the theory which
> would suggest that 4 users should work on a ordinary ADSL link (where
> the upchannel of 256kbs is the bottleneck).
>
> Luckily it's something that you can experiment with without making any
> serious investment. In practise we have many 2-8 extension users on
> ordinary ASDSL lines. As they grow they tend to get a dedicated ADSL
> connection for VoIP then move to SDSL.

Oh dear!

I really am out of the loop on DSL!

I didn't know that SDSL was available this side of the pond!

[ Post a follow-up to this message ]

In article <1140453161.873113.6650@g47g2000cwa.googlegroups.com>, cjd
<colin@talk21.com> writes
>A thread was started on that here:
>
>http://www.voipfoneuserforum.com/viewtopic.php?t=104
>
>It's 'how long is a piece of string' question finishing with 'it all
>depends'.
>
>The real world effect is very hard to predict from the theory which
>would suggest that 4 users should work on a ordinary ADSL link (where
>the upchannel of 256kbs is the bottleneck).
>
>Luckily it's something that you can experiment with without making any
>serious investment. In practise we have many 2-8 extension users on
>ordinary ASDSL lines. As they grow they tend to get a dedicated ADSL
>connection for VoIP then move to SDSL.
>
I would suggest 3 possibly 4 IP phones on one ADSL, but be prepared for
quality to suffer if all 4 are active at once. - This on an ADSL line
dedicated to the IP phones.
If they are a charity, and hit the phones to generate donations, it will
be worth having 2  BT lines.
Philip Partridge

[ Post a follow-up to this message ]

The thing to do is just try it.

If the ADSL link, PCs and LAN exists, the investment is 4 headsets from
ASDA =A37.00 each (although in the end you'll want to buy real SIP
telephones), four PBX extensions (99p each per month) and whatever
calling credit you want to buy.

The alternative is 2 ISDN circuits and a local pbx switch, which is a
lot of investment and a very high running cost.

[ Post a follow-up to this message ]

cpvh@uk2.net wrote:

> Oh dear!
>
> I really am out of the loop on DSL!
>
> I didn't know that SDSL was available this side of the pond!

It would have to be a pretty small pond, as it's only up to 1.6km from the
exchange ;-)

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This is my BOOOOOOOOOOOOOOOOOOOOOMSTICK

[ Post a follow-up to this message ]

On 20 Feb 2006 02:02:17 -0800, cpvh@uk2.net wrote:

>What I couldn't find there was any recommendations as to what "speed"
>ADSL line might be required for 4 simultaneous VOIP conversations.
>
>Anyone any idea on this?

Regardless of downlink speed, most ADSL has an uplink of 256k. Which
means that you will be OK with three conversations, but if you want
more, you will have to use a codec that uses less bandwidth, probably
at the expense of quality.

Four will run on a 256k uplink, but not on 711u

[ Post a follow-up to this message ]

hairydog@despammed.com wrote:
> On 20 Feb 2006 02:02:17 -0800, cpvh@uk2.net wrote:
> 
>
>
> Regardless of downlink speed, most ADSL has an uplink of 256k. Which
> means that you will be OK with three conversations, but if you want
> more, you will have to use a codec that uses less bandwidth, probably
> at the expense of quality.
>
Or if you're using 726 or 729 at the expense of runtime.

> Four will run on a 256k uplink, but not on 711u

I guess it depends on how reliably you can get 256k to the gateway.

[ Post a follow-up to this message ]