#5 Transmission of pktmetas

[Marco Canini]

There's no way to share the mapping between pktmeta
names to pktmeta types in two como nodes.
In the case the mapping is not the same you'll get
weird things.
It's important that when a como node contacts another
como node it receives a mapping of pktmetas in use by
the second como node.
This mapping should be used for the packets received
from that node.
The mapping could be cached but it shouldn't affect
performance anyway.
If cached you have to make sure you get a new one when
updated.
Also the mapping might change during the query, that
might be hard to handle. It's probably better to
enforce the module to declare all the pktmetas that are
used.