Re: rfc 1122 and ICMP SOURCE HOST ISOLATED

[Gabriel Montenegro <[e-mail]>]

> If there is no carrier on your ethernet interface should your kernel
> synthesize Dest Unreachable code 8 when you try to send out that ethernet
> interface?  Does anyone actually do this?

That's what we're trying to do. We're thinking of nomadic
or portable hosts. This implies intermittent network connectivity
so it would certainly help to have a *hard* indication of when
no network interface is available--and won't be, perhaps for the entire
duration of the user session. The system can then take this as a hint
not to wait forever when it tries to access the network, expecting
the server or target system to eventually respond. Instead, a quick
failure with the indication that the network is down/not available
is the best course of action. As a user, I'd rather get a quick error
message than a system hang.

Nomadic software can also use this as a hint to use local caches,
log network activity to be replayed when reconnected, etc.

-gabriel montenegro