@cam routing


PPSW uses a CDB table
data from Jackdaw

Most @cam email comes from Hermes
and then goes straight back

Exim on Hermes and CUS uses the "iplookup" router to query Jackdaw directly about how to route an @cam address.
reduces load on PPSW and Hermes
falls back gracefully to routing via PPSW if Jackdaw is down