[Asterisk-Users] How does Vonage support fax machines?

[Glenn Powers]

Deon wrote:

>My boss is insisting we support fax, and I keep telling him that Fax over
>IP is very unreliable and not recommended and his immediate come-back is
>"Vonage does it." and it's very hard to figure out how.
>
>I don't think Vonage does T.38, the Linksys/Sipura units they're using
>doesn't support T.38 to my knowledge. 
>
>That means they have to be using G.711Ulaw to send faxes. But how do they
>compensate for packet loss/jitter/etc.
>  
>

They don't. I've tried faxing through Vonage. It works *sometimes*. 
Vonage *claims* to do fax, but they don't do it even somewhat reliably. 
If someone thinks differently, have them try it. (Yes, it's just Fax 
over VoIP, ie encode the fax modem in g711u and hope for the best. If 
packets drop, the fax dies.)

cheers,
glenn