How May Voip Calls On Given Bandwith?

[nemo38]

How many simultaneous VoIP conversations could you have on the various internet connections available in Thailand?

For example, on the corporate packages offered by www.maxnet.co.th (dedicated lines, no sharing)

256/256 ?

512/512 ?

1024/512 ?

2048/512 ?

I just have no idea how much bandwith is taken up by decent quality VoIP. I don't know if the 2048/512 can support 1 or 20 conversations. Any ideas?

[Carmine6]

How many simultaneous VoIP conversations could you have on the various internet connections available in Thailand?

For example, on the corporate packages offered by www.maxnet.co.th (dedicated lines, no sharing)

256/256 ?

512/512 ?

1024/512 ?

2048/512 ?

I just have no idea how much bandwith is taken up by decent quality VoIP. I don't know if the 2048/512 can support 1 or 20 conversations. Any ideas?

There's a test and a chart on this website that should help:

http://www.talkswitch.com/voip/voip_test.asp

Entering 256kbps gave this result:

Using codec G.711, you can make up to 2 simultaneous VoIP calls

Using codec G.726, you can make up to 4 simultaneous VoIP calls

Using codec G.729, you can make up to 6 simultaneous VoIP calls

Oh I forgot, raw speed isn't the only criteria since the packets have to arrive in the right order or close enough. So the stability of the connection matters a lot.

Edited August 20, 2007 by Carmine6

[OlRedEyes]

Well I have a 2Mb Cat line, and it supports one conversation, sometimes, sort of

[monty]

In Thailand the upload speed is pretty much always limited to 512 kbps.

So the simultaneous connections possible has to be calculated on that speed!

Not much use if you can hear the other side perfectly, but they can't hear you because of your limited upload capacity!

I would guess on average a single connection would eat between 60 and 100 kbps, so with some spare capacity the maximum on 1 line in Thailand will be 4 or 5 connections!

[gregb]

How many simultaneous VoIP conversations could you have on the various internet connections available in Thailand?

For example, on the corporate packages offered by www.maxnet.co.th (dedicated lines, no sharing)

256/256 ?

512/512 ?

1024/512 ?

2048/512 ?

I just have no idea how much bandwith is taken up by decent quality VoIP. I don't know if the 2048/512 can support 1 or 20 conversations. Any ideas?

There are lots of answers to your questions, but as a general rule, if you are using a Thai based VoIP service that cares about conserving bandwidth, you will get about 1 call per 20k - 22k of bandwidth.

Please remember that your ADSL speeds are wire speed, and do not include the framing overhead. VoIP packets are small, so framing overhead becomes significant. Multiply the lower of the 2 numbers by 80%, divide by 22k, and you get some indication of the best you can hope for. You probably won't get that except at 2 in the morning, but that is the theoretical best you can expect.

If you are using a VoIP service provider in the US who cares nothing about running G.711 without VAD and negotiates it by default, forget about running more than 1 - 2 simultaneous calls over ADSL.

This is overly simplified, as local companies can misconfigure equipment to be inefficient, and US based carriers can be configured to conserve bandwidth if they want to (they usually don't care however.)

Give us more information about your proposed VoIP service and we can be more specific.

[nemo38]

Give us more information about your proposed VoIP service and we can be more specific.

Thanks for your help Greg. Simple application - just contact between Thai office and US office. But this could climb to a few dozen simultaneous conversations.

On the US side someone just answered my question by telling me the VoIP connections would consume from 1.5kbps to 8kbps per call.

Given that the limitation for two way comms is on the up side I would go for 512/512 with perhaps multiple connections added later.

Reliability is very important for me. Otherwise I'd just connect using cheaper non business lines.

Anyone here use a biz rate connection and can tell me how reliable they are?

[technocracy]

One thing that seems to have not been mentioned and probably the most important is that VOIP over the Internet isn't recommended since you have no control over congestion or prioritization of packets. The Internet is a fire it and hope scenario, on route sometimes you might not encounter congestion but alot of the time you will.

DSL is also a contended service (normally 50:1 if lucky 20:1 - but in Thailand . . . I don't know) so if your exchange is a busy one the congestion could well be happening at the first ingress point of the network.

Personally I would never recommend to any client to use VOIP for business use over the internet - only on an network where they can control the priority of the packets.

As for the services that maxnet are offering well looking at the Corporate Biz it doesn't appear to be much different (although I can't read the Thai) other than you get a better router with dial-backup - which is a total waste of time - why would you want to use a 56k dial up after you are used to 2meg!

But as I say regardless of your connection to the internet even if you had a 10Gig Ethernet link once that traffic head into the Internet you are at the will of any service provide and atlantic carrier links along the way to whether your VOIP call will be successful.

[nemo38]

>VOIP over the Internet isn't recommended

VoIP stands for Voice over Internet Protocol. Some companies offer VoIP services over their own backbone. Are you saying that VoIP software, such as skype, is used over proprietory back bones?

>DSL is also a contended service (normally 50:1 if lucky 20:1 ..)

Biz lines are not contended. That is why they carry such a whopping price premium over domestic lines.

Latency and jitter are a concern. But I don't know what the figures are from biz lines on any given ISP.