Bug #276

Seems likely this is some sort of SNMP broadcast protocol being used to discover the printers on the network, according to CUPS documentation.

http://www.cups.org/documentation.php/network.html

Just to verify, the jetdirect protocol itself, works across the networks, it’s just discovery that is borked?

I note that guests should NOT be able to access printer resources on the secure lan.

As for addressing this:

samba can run on the router, providing a central rendezvous point for printer information.
mdns - if implemented, and I thought it was in cups LONG ago, should also be able to do the trick,
but this would be a good test.

It’s the discovery of the printer (via snmp broadcast) that seems to be the problem here, if I read my tea leaves right. The cups configuration stuff on Linux (and maybe mac) seems to use it to find printers when configuring a new printer.

To confirm this theorya, we need to do a little bit of wire sniffing.

This begs the question of how common this use of snmp broadcast is in other applications and operating systems.

I need to sniff to see what is happening when on the same segment so we can figure out what the next step should be. See if SNMP theory of jg is correct….