# Voice over IP

## BWoso

I am at school and we have wireless internet and I was wondering if there was a way to use voice over IP on the wireless internet. Thanks, Brandon

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## viperlin

yes

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## UltraN00B

reminds me of the clipper chip

http://news.com.com/2100-1023_3-212492.html

http://209.157.64.200/focus/f-news/1055411/posts

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## viperlin

lol, ok now i'll expand on yes since BWoso hasn't.

if you have access to the wireless network then you can use software over it, VoIP is software so why wouldn't it work? it's like asking if quake would work, of cource ,assuming you've got someone to play with/talk to  :Smile:  and assuming you have some VoIP software

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## TerminalAddict

I'll tell you why it won't work

Wireless IP (as in TCP/IP) send byte packets ranging from 0-1500 bytes, sometimes more ... IP is design to speed the transfer up until it reaches it max, then slow it down a bit .. so when using a data connection often 1500 byte packets result in throughput of 8MBs

Voip REQUIRES 100 byte packets ... over a Radio/Wireless connection, this results in about 8-9kbs (thats kilobits) meaning the voip throughput is SHIT!

this can be fixed  :Wink:  ... put QoS  at either end of the radio link, and use a proper Voip/IP bridge.

A bridge will successfully agregate packets so that the throughput on IP can be imporved. The QoS is used so that the Voip gear gets priority over data connections.

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## BWoso

Sorry about not responding I was having some major problems with Gentoo and still am, so now I'm using Mandrake for the time being.  I will probably be doing this on window machines since that is what most people have, so I will use my roomates box and then whoever we want to talk to. Could someone explain a little bit more on how to do it?

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## mvr_rennes

 *TerminalAddict wrote:*   

> I'll tell you why it won't work
> 
> Wireless IP (as in TCP/IP) send byte packets ranging from 0-1500 bytes, sometimes more ... IP is design to speed the transfer up until it reaches it max, then slow it down a bit .. so when using a data connection often 1500 byte packets result in throughput of 8MBs
> 
> Voip REQUIRES 100 byte packets ... over a Radio/Wireless connection, this results in about 8-9kbs (thats kilobits) meaning the voip throughput is SHIT!
> ...

 

Hi, I think you've got some things confused... IP does not do any kind of rate control, so your 8MBps throughput is bogus.  Rate control is done by TCP and some other TCP-friendly transports, but most VoIP apps run on RTP over UDP, as TCP is not suitable for real--time applications (if packets need to be re sent, they'll surely arrive too late to be useful, and in any case, the resulting jitter would be way too big).

Again, I don't know who told you that VoIP "REQUIRES" 100 byte packets, but that's wrong too. Voice packets usually contain between 20ms and 80ms of coded voice, which depending on the codec used, can take anywhere from 20 to 512 bytes, maybe even more. For instance, with GSM you get reasonably good quality @~13kbps...

Again, I don't know how you came up with your 8kbps limit, but that's bogus too, unless you believe that modern cellphones do not work, that is  :Wink: 

So, to the original poster: go ahead and try it out. It is most probable that  most of the quality loss won't come from the Wireless network, but from losses and delay in the route to the host you'll be talking to. (unless you're thinking about using it in-campus, in which case it'll probably work just fine).

Cheers,

M

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## BWoso

I would probably just be using it on campus because of the fact that it is really hard to people to reach your person computer from off campus, like I would have to do a whole bunch of work to get an ftp server up because of all the the routers and firewalls that the school uses so that you can not abuse the network.  Now that I know that it is possiable can someone send me a link to a good program to use for VoIP or explain to me how to set it up. Thanks

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## TerminalAddict

ok perhaps I missed somethings

the 8MB comes from a 10MB link = 10MB - overheads (wep encryption etc etc)

I have a Voip phone on a 2.4Ghz radio link which agregates packets and sends out 1500 byte packets, which is crap for realtime apps such as Voip

I also have a 10MB 3.2Ghz link which agregates DATA packets, and QoS's Voip traffic, and the Voip phone wortks like a charm.

The experiences I have encountered has been that Voip needs to 100byte (or less) UDP packets, and this dramatically reduces throughput on a radio link, because it overrides the modularisation of the radio.

I purchased a "MAGIC" Voip bridge (pair) and they seem to preform a whole lot better over my 2.4G link, however, still perform much better over my 3.2G link

info:

2.4G is using standard 802.11b orinocco cards with "Turbocell" firmware loaded

link: http://www.karlnet.com/Documents/WhitePaper/TurboCellWhitePaper/TurboCell%20White%20Paper.htm

3.2 is using Remec radios, and is a licensed band here.

link: http://www.remec.com/products/market_results.cfm?market_key=1&category_key=6&type_key=33

I also have a 5.8G link, using Trango radios .. and voip works nicely over that  :Wink: 

link: http://www.trangobroadband.com

Voip bridges are Allied Telesyn VP604 FX0 and FXS

link: http://www.google.co.nz/search?q=cache:QJ_DtygsS9cJ:www.disti.ba/CD/alliedtelesyn_complete_uk.pdf+at-vp604&hl=en&ie=UTF-8

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## etnoy

 *BWoso wrote:*   

> Sorry about not responding I was having some major problems with Gentoo and still am, so now I'm using Mandrake for the time being. 

 

Poor man. I do really feel sad for you

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## BWoso

Yeah, this was posted a long time ago and it took me about a day to get my gentoo system back up and running so I didn't use Mandrake for that long, but still going to Mandrake when broken is better than going to windblows.

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## abzs2k

 *BWoso wrote:*   

> Now that I know that it is possiable can someone send me a link to a good program to use for VoIP or explain to me how to set it up. Thanks

 

 :Very Happy: 

How about this? 

I have the feeling that I will not be liked for this...  :Laughing: 

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## bos_mindwarp

KPhone (emerge kphone)

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## BWoso

Awesome, thanks for the programs.  I had kinda gave up on doing this since it wasn't real important to me and it had been over a month since anyone had posted anything, but I will try those programs.  Thanks again

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## STEDevil

Kphone & Linphone, the current SIP phones avalable in portage, both blow chunks. They are pretty much unusable as phonesoftware IMO.

This soft is a LOT better if you actually want to use it as a phone http://www.sjlabs.com/

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## Deathwing00

Moved from Off the Wall.

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