Hi all,
Here are the other technical corrections, clarifications, and two or
three changes we propose to make in AUTH48 for the DCCP spec.
CORRECTIONS AND CLARIFICATIONS
- Options are explicitly allowed to declare how they behave when
Mandatory.
- The FGSS feature (Section 6.6.4) claimed that retransmitted Change
options always have the same data; this is not true. Correct it.
- (8.5) Explicitly show when packets with short seqnos are dropped
when they aren't allowed.
- (8.5) Explicitly show when short seqnos are extended.
- (13.2) Elapsed Time should be a LOWER bound, not an upper bound.
TECHNICAL CHANGES
- Allow multiple Init Cookies. The server can send multiple options,
all of which the client will echo in the same order. This avoids the
253-byte option length limit.
- NDP Count option can take up to 6 bytes of data (since sequence
numbers are 6 bytes long).
- (7.5.3) We advise Sequence Window be set to the number of packets
in 5 RTTs. This conflicts with the definition of "active
connections" (as receiving packets within 5 RTTs), since it leaves so
little slack. Say a connection is speeding up, and sends Sequence
Window packets in 3 RTTs. This is not insane. Now assume all those
packets are lost. The endpoints can't get in sync for another 2
RTTs, until the connection becomes inactive. For that reason, we
propose to redefine the "active connections" window to three RTTs
rather than five, introducing some slack.
- (8.1.2, IANA) Rather than talk about "ASCII" Service Codes, talk
about Service Codes that follow the guidelines we've laid out for
"SC:". (Mark)
- (Appendix A) Add the "ack_runlen" variable, which is required to
get O(1) acknowledgement processing.
Eddie
