Merge branch 'cid-len-vn'

draft-ietf-quic-transport.md

@@ -4563,9 +4563,11 @@ connection IDs gives clients some assurance that the server received the packet
 and that the Version Negotiation packet was not generated by an off-path
 attacker.
 
-As future versions of QUIC may support Connection IDs larger than the version 1
-limit, Version Negotiation packets could carry Connection IDs that are longer
-than 20 bytes.
+Future versions of QUIC may have different requirements for the lengths of
+connection IDs. In particular, connection IDs might have a smaller minimum
+length or a greater maximum length.  Version-specific rules for QUIC packets
+therefore MUST NOT influence a server decision about whether to send a Version
+Negotiation packet.
 
 The remainder of the Version Negotiation packet is a list of 32-bit versions
 that the server supports.