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x25/qllc to llc conversation without x25 int


i have to following problem:

there is a 3640 router in the distribution-layer, which recives x25 calls over a xot cloud.

that means i have encapsulated x25 (sna/qllc inside) in tcp/ip with xot.

this 3640router decapsulates the xot-data so it has the raw-x25 frame and forwards the x25 frame(sna inside)

over a physical x25 interface to the x25 cloud.

now the idea is, that the 3640 should translate the x25-frames (qllc) to llc-frames.

if this is done, the 3640 could forward those data over dlsw to our cip-router, which forwards the

data to our mainframe.

the reason for this is that i do not need x25-switches in the distribution-layer.



the 3640 receives the xot frame and decapsulates it so that the router has the raw x25-frame "inside".

now - i must have a physical x25 interface on the 3640 where i forward the x25-frame.

==> one x25 interface !

this x25 interface will not go up till there is a second one which generates clock, x25 dce, ...

and receives the x25 call

==> a second x25 interface

so the 3640 receives the xot-frame - decapsulates it to the raw x25-frame -

forwards it out of the first x25 interface - which is connected to another physical x25 interface on the 3640

(over a dce/dte x21 Cable) - the second x25 interface receives the x25-data and could then do a

qllc/llc conversation - which is then forwardet over dlsw to our data-center !

this really complicated and i need 2 interfaces with x25 encapsulated only for that, that the x25 frame

goes out of the first interface and is received on the other interface.


my first idea was to create a kind of loopbackinterface where i can define "enc x25" - but that is not possible.

does anyone in the big world has an idea how this could be made without the 2 x25 interfaces ???

thanks and greetings from austria --


Re: x25/qllc to llc conversation without x25 int

I am of the view that your first option is going to work. I have never seen a case where a router does a second lookup.

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