SIP/GSM Gateway

[ritsadmin]

ok - am waiting delibery of the Nicherons product suggested. Will let you know how I find it. Thanks for the suggestions.

[davrays]

A major problem with VoIP generally is echo. Echo is most noticeable when there is delay.

The idea if you can reduce delay, even if there is echo, it may not be objectionable, if the delay is small.

So, at every stage, look at reducing delay. This means using g711 CODEC.

g729 introduces too much delay and the voice quality is just that little better using g711 which important for business where you may need to quote letters and numbers for orders etc.

Daryl, although I am generally agree to you about the echo, but there is something new to me in this post.. Why do you think the G.729 adds delay? I have never listened this and didn't experience too, and also I don't see any reason why it should do so (given that RTP is configured to have standard 20msec packetisation interval). Just curiuos...

[KSComs]

Daryl, although I am generally agree to you about the echo, but there is something new to me in this post.. Why do you think the G.729 adds delay? I have never listened this and didn't experience too, and also I don't see any reason why it should do so (given that RTP is configured to have standard 20msec packetisation interval). Just curiuos...

My gutt tells me that perhaps the delay is more to do with the GSM network than anything else ???

I have found that depending on the carrier it can take from 5 to 12 seconds for a call to be established, and because of the transcoding involved at which ever point, could also add further delay...

That said.... traditionally the GSM network is full of points of latency and it doesnt matter what codec is used... there will be delays...

GSM / Mobile network can have up to 300ms + latency... it has nothing to do with the telephone system that the GSM Router is plugged into..

Try this...

From your own phone ... call your mobile.... and speak into the mouth piece of the phone and hear it in the mobile... latency occurs and in Oz ..

In Oz we have 3 / Vodafone / Optus / Telstra and every other man and his dawg offering GSM calls...there are distinct differences in the GSM networks... you will hear the difference... but you pay for what you get. !!!

Kev

[ritsadmin]

I received the Nicheron product and I am pleased to say that in a lab it seems to work very well. I do have one slight issue (relating to outbound authorised voip lists - it seems not to care about only allowing the sip callers I have authorised) to be able to call over the g/w - probably something stupid in my config) but that aside I think it looks pretty good.

Thanks Daryl for the recommendation.

[edgarlopes]

Hi every one

It's very easy to solve all the poor quality problems with the portech Gateways

Just instal an internal STUN server, configure the portech to use it and... Voilá

No more problems

Best regards

[colton1237]

It is good and works well... just a crappy gui that doesnt work with the latest browsers / java .. and a console program that is designed for pre windows vista / Win 7 etc... apart from that it works a treat...

[shandy7894]

I have decided to chance it and test a portech - they are less than 200 euros and the only limitation I understand with the unit is that they don't like 3g/hspda enabled sim cards.
I'll let you know if I need to order an alternative !

[joebloggs]

Hi All,
I’m due to set-up my own telesales business and have heard about gsm gateways (www.packetmedia.co.uk/gsm_gateways.html) and that they can reduce you landline to mobile calls down by at least 50%. I’ve found these guys Packet Media (www.packetmedia.co.uk) and they seem to install them free on a contract term?? Anybody had any experiences with GSM Gateways???

[joebloggs]

Hi All,
I’m due to set-up my own telesales business and have heard about gsm gateways (www.packetmedia.co.uk/gsm_gateways.html) and that they can reduce you landline to mobile calls down by at least 50%. I’ve found these guys Packet Media (www.packetmedia.co.uk) and they seem to install them free on a contract term?? Anybody had any experiences with GSM Gateways???

[lunacom]

I recommend TOPEX MobiLink GSM gateways (problem zero with pbx Epygi), if you have the QuadroCall Pro (Ver.3.10) software, you can send SMS from PC!