[Asterisk-Users] Port density: DS3 cards?

[Tilghman Lesher]

On Thursday 04 December 2003 14:06, John Todd wrote:
> Obviously, there are no DS3 TDM cards that are currently compatible
> with Zap channels.  (or are there?)

This isn't so much a technological limit as much as a detail of
implementation, but the current Zaptel drivers have a limit of 252
channels per machine.  This is due to each channel number getting
assigned a device minor number, which has a limit of 256 (4 are
reserved by zaptel for special purposes).

Any attempt to write a driver for a DS3 card should take this into
account.  I don't know if expanding beyond 252 would be an easy change
to the Zaptel architecture or if this would require a major change to
the way the drivers are written; but it is a limitation that needs to
be considered.

-Tilghman