[asterisk-dev] Alternative Clock Source

Michael Cargile mcargile at explido.us
Mon Jun 11 06:15:50 MST 2007

> Also, I need to clarify what do you mean when said "to provide
> channels". Could you please?

What I mean by providing channels it that zaptel hardware not only
provided a timing source to Asterisk but also a channel driver for tdm
devices such as FXO ports and T1 cards. We are planning on being able to
specify in the host operating system which virtual machine to pass spans
to. That way we can divide an eight port T1 card up amongst 4 Asterisk
instances. We plan on doing this in a similar fassion as Zaptel over
Ethernet. Technically you could do this anyways by running an Asterisk
instance in the host and the VMs, then use ZOE between them, but that
basically defeats the idea of running Asteirsk in a VM which is to
seperate instances from each other. Plus you would not get the timing
benifits from the physical zaptel device in the VMs.

So anyways I am of the opinion that if the device you are using to get
your timing is able to place a phone call to the PSTN in some fassion
you should create your own zaptel driver. If not just create a patch to

Michael Cargile
Explido Software USA Inc.

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