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Telebit stac compression incompatibility


I have a very very old telebit router. When I say old, I mean it, even the internal clock in the router was going backwards last time I saw it =)

I have ppp connection with a cisco 3600 router IOS 11.3 and I wanted to try out the compression options.

Telebit supports only stac compression, here is the command output

netblazer:Top>Configure>PPP> compress


Usage: compress default|<interface> [off|stac] [<option> <value>]

## STAC options: history, check

history values: nohistory, single

check values: nocheck, lcb, crc, seq




I tried every different combination of compression options but I could never make it work with cisco. Although both router's agree to work with stac compression. It just doesn't work.

Is there any workarounds for this or this is a known incompatibility? although

I think this should be a standart feature of ppp when you use stac. How can there be incompatibility?



Re: Telebit stac compression incompatibility

First of all, it is possible that there is a bug on our part, so upgrading to more recent code is recommended. With STAC, we will first try to negotiate LZS_DCP, then LZS. We will keep a dictionary, and will use a 1 byte sequence number only for DCP. I'm not sure how the telebit should be configured...if you've tried every combo, there may not be an alternative. Even though STAC is standardized, bugs or implementation issues can still cause problems.

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