Re: Question on HDLC and raw access to T1/E1 serial streams.

From: Krzysztof Halasa
Date: Sat Sep 30 2006 - 13:34:54 EST

Ben Greear <greearb@xxxxxxxxxxxxxxx> writes:

> I am looking for a way to bridge a T1/E1 network by reading a raw
> bitstream from one T1 interface and writing it out to the other. The
> application is adding delay and/or bit corruptions for impairment
> testing.
> I have been using Sangoma's drivers and NICs, but I'm having no luck
> getting their latest stuff to work so I was hoping to use in-kernel
> drivers (even if that means writing or hiring someone to write new ones.)
> Is there currently a way to read/write the raw bitstream for a full T1
> or E1 or a subset of channels?

Well, my generic HDLC works with HDLC framing only, T1/E1 is
a layer lower than that... I think Cyclades have (had?) a version
of PC300 card with T1/E1 interface. It at least doesn't require
any "binary blobs", though I think the driver would need some work.

Which line interface do you need? G.703?
Do you need to bridge multiple streams (not slots) over one
interface (internal (de)multiplexer - I mean "more than one
subset of channels")?
Krzysztof Halasa
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