In article <fg1qee$10u$2$8300dec7@news.demon.co.uk>,
kevin bailey <kbailey@freewayprojects.com> wrote:
>Gordon Henderson wrote:
>
>> In article <fg0a71$ln2$2$8300dec7@news.demon.co.uk>,
>> kevin bailey <kbailey@freewayprojects.com> wrote:
>>>Hi,
>>>
>>>I'm looking to use mobile handsets to make/receive VOIP calls back to our
>>>VOIP server.
>>>
>>>This would mean that the handset would need to have a SIP client installed
>>>- and for the network provider to allow VOIP calls over the data network.
>>>The phone should also be able to connect via wi-fi.
>>>
>>>Currently I've been advised that using E65's on Three's network works in
>>>this way and this is looking like the choice I'm going to go for.
>>>
>>>Just thought I'd check to see if there were any other combinations to
>>>compare this to.
>>
>> I've been using a Nokia E90 to asterisk servers via Wi-Fi and it's
>> working well. Not tried it via packet-data yet though, as I'm on O2
>> and not signed up to a nice data package yet....
>>
>> Gordon
>
>Thanks for that - gives me another option on the phone side.

I have to say I'd never personally recomend using Wi-Fi for VoIP
though. Just too many things to go wrong with it, and too easy for an
access point to be abused by someone else using it to download or upload
large data streams rather than VoIP.

Don't forget that Wi-Fi is half duplex - and VoIP is full duplex. No
issues if the bast station and handset can do the link turn-around in
a timely manner, but VoIP is typically running at 50 packets per second
each way - with 160 byte packets. That's almost at the limit of what most
Wi-Fi AP's are capable of as they were really designed with streaming
a lot of data in one way, so large 1500 byte packets...

It's usable, but I'll never sell any Wi-Fi systems to clients!

If you need a mobile handset in a fixed, small area, then use DECT, or
use a mobile phone as a mobile phone with the GSM/GPRS/3G voice network.

Gordon