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Re: TO COMPRESS OR NOT TO CMPRS (please reply)
Dear Angelos:
>... However, just what is the model in mind ? I doubt firewalls need to
>perform compression; most companies have decent speed links to the
>Internet, so compression there wouldn't buy much.
One of the most likely scenarios for the use of IPSEC, I think, is between
an organization's firewall and a dispersed community of users communicating
over public dial-up Internet access services, with physical connectivity
via phone lines or similar. Where the organization runs its servers,
support would tend to be deployed in the firewall, at least initially,
because the firewall represents a single point through which all external
traffic passes.
If compression were done at the Network Layer, then this firewall would
need to "wrap" or "unwrap" the compressed data. If compression were done
at the Link Layer (e.g. PPP), however, then this firewall would never see
it. It compression were done in upper layers, it would pass transparently
through this firewall.
>A couple more points:
>a) i think the only place compression would buy anything, especially
> networks become faster, is the "last mile" (as Steve Bellovin
> said); the 28.8 (or so) PPP link. Now, PPP already has compression
> for that link (or so i remember)...
If the dial-up 28.8 users are doing IPSEC, then the PPP compression will be
ineffective. Not so?
Cheers,
-- Scott
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