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Modems over SIP

Modems over SIP

Modems over SIP

Well this forum seems to be dead but I thought I would ask what success people are having using dial up modems over SIP. Reason I ask is in Australia we are rolling out our National Broadband Network and people are being forced off the old PSTN and onto SIP and I have a customer who deals with one of his customers in a remote location (Christmas Island) and can only use dial up. So what do people suggest for people who are forced to use dial up in these circumstances?

Thanks in advance if anyone is still out there!

RE: Modems over SIP

I have gotten analog Fax working over SIP, but it sometimes required lowering the baud rate to 9600 or lower.

If the remote device you are dialing in to is Serial only, you could get a Serial to Ethernet adapter, such as one of the many products offered by Digi, then connect to it via a VPN or other method through the internet connection at the far side.

If dial-up is the only internet connection available (No DSL or Cable Modem, you may want to look a Data only cellular connection, and a VPN back to you for remote management. If it needs to be on-demand, you could setup the dynamic DNS for the remote end, and manually initiate the VPN from your end as needed.

Good Luck!

RE: Modems over SIP

Hi OzzieGeorge,

Yes, this forum has quieted down a lot since a few years ago! I'm also to blame since I haven't logged on here for a while!!! neutral

The NBN is definitely annoying a lot of people with faxes, EFTPOS machines and security systems, but it is still possible.

If you really want to avoid problems, you need to get a fax machine that's got the ability to use the T.38 protocol. This protocol was specifically designed for sending faxes over packet-switched networks like the NBN/Internet. I would also set the baud rate to 9600 just to be safe.

I would also recommended getting a data plan that is in the middle or higher.

Let me know if you have any further questions.


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