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New Member

x25 asymmetrical w/p and XOT

Hello, I do have a general question regarding X25 asymmetrical packet/window size.

We would like to add on an existing X25 routerA a new conx via XOT to routerB, so we have:


As routerA/B do have asymmetrical w/p size configured I think I need to use the flow-control nerver cmd and the local ack x25 routing?

routerA does not have the local ack configured right now, does this give problems when I add the cmd to routerA for the existing conx ?

Or can I use 'x25 routing acknowledge local' without any problems?

Thanks for help, Thomas

VIP Purple

Re: x25 asymmetrical w/p and XOT

Hello Thomas,

the local acknowledgement is required; since it allows packets to be sent without waiting for an acknowledgement from the remote side; it should usually increase throughput, but should not affect your current connections.

As for flow control, that is an optional feature, and not required.

Have a look at the following documents:

X.25 Switch Local Acknowledgment

Feature Overview

X.25 Asymmetrical Windows and Packets



New Member

Re: x25 asymmetrical w/p and XOT

Thx GP for answer,

I have reviewed your links before but was not quite sure if it has an influence in the exsiting conx.

Up to now we haven't configured 'local ack' and the call from DTE1 fails at routerB side, the call

arrives via XOT, sent out the serial interface to the X25 net, it is confimred by the net and immideatley

is cleared by routerB with cause5,diag64 (call setup problem, Network congestion) and I think

it is due to the fact that the XOT reports other window/packet size than the serial line on routerB is configure.

So I hope with the local ack configuration we will solve the issue,

thanks again for your help, Thomas

VIP Purple

Re: x25 asymmetrical w/p and XOT

Hello Thomas,

the call being disconnected right away indeed sounds like a typical symptom of the differing window/packet sizes. I, too, would guess the local acknowledgement solves this...



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