CARD issue#30: L2 type indicators to be assigned by IANA

One of the comments to the L2 ID sub-option was that
"L2-type" identifiers need to be assigned by IANA.
Now, I assume that in case we ask IANA for type
identifiers, we need to give also a list of interface
types. This lists needs then to be extended later for
future technologies...
I am not sure if this is really required for the
experimental protocol. Take into account that using
the L2-type identifier has been indicated to be
optional.

Comments?

marco