I finished a revision of the SC draft (rev -02) last month. In this
revision, I decided to step-back from the problem of easier allocation
of server ports to Service Codes.
One possibility would be to find a way to allow easier allocation of
DCCP server ports (e.g. also from a specific DCCP Registry covering the
dynamic port range (not allocatable for TCP/UDP, etc)). This does not
seem to cause conflict with the new spec., but has drawbacks....
I now have another proposal for which I'd appreciate feedback:
The specification defines a default server port that is formed from a
specified hash of the SC value to a part of the dynamic range
49152..65535. This method could result in overlapping allocations (but
these would be statistically rare, and not a problem per-se). It would
NOT preclude a server application using a well-known port from the port
registry (as currently), or other value negotiated by some other means
(e.g. SIP, RTSP,whatever...). I suggest that this hash-approach could
eliminate the need for a port registry entry for every SC: all
applications that have SC allocations would immediately have access to a
"well-known" server port.
Does anyone have thoughts?
Does anyone have a hash algorithm to recommend?
best wishes,
Gorry