Subject: New MADCAP draft -05

From: Steve Hanna <[email-masked]>
Date: Tue, 25 May 1999 11:45:08 -0400

As you have seen, a new version of the MADCAP spec has been posted at

http://www.ietf.org/internet-drafts/draft-ietf-malloc-madcap-05.txt

This version reflects the outcome of discussions with our Area Directors
and others. A list of significant changes is included below. Many minor
changes were also made, such as fixing typographical errors.

Please review these changes and send email to the malloc list or the
authors if you have any concerns.

Thanks,

Steve Hanna

---------------------

* Renamed Client Identifier to Lease Identifier.
* Changed INFORM's code to 8 throughout the document. It used to be
  0 in some places and 8 in others.
* Changed SHOULD to MUST and MAY to SHOULD in several places to
  improve probability that conformant implementations will interoperate
  successfully.
* In section 2.2.8, changed text to say that Minimum Lease Time and
  Maximum Start Time MAY be included in a RENEW message. Also
  mentioned that if Start or Max Start is included, Current Time MUST
  be. Also explicitly described defaults if options are missing. These
  defaults are different than what was implied (but not explicitly
  stated) before. For instance, Lease Time defaults to max available
  instead of whatever's remaining in the current lease.
* INFORM messages now MUST include an Option Request List
  option. Before, this was optional.
* In Table 5 (Options allowed in MADCAP messages), ACK in response to
  RELEASE MUST NOT include Current Time. ACK in response to INFORM
  still MAY include Current Time, since the client may have requested
  Current Time using the Option Request List.
* Described risks of making it easy to guess a Lease Identifier.
  Suggested using a cryptographically random number generator.
* Added new Error option. Only allowed in NAK. See section 3.17 for
  details.
* Servers SHOULD NAK errors unless this might cause a NAK loop. See
  section 2.6 for details.
* All constants are now listed in a new Appendix B. All constants now
  have RECOMMENDED values that should work nicely together.
* Added more discussion of clock skew. There are separate constants
  for [CLOCK-SKEW-ALLOWANCE] and [EXTRA-ALLOCATION-TIME] now. These
  MUST be configurable.
* [RESPONSE-CACHE-INTERVAL] MUST be no more than 5 minutes now.
  This allows the client to safely reuse an xid, msgtype, Lease ID
  combination after 10 minutes.
* Mention server doesn't need to cache a packet if it ignores it.
* Recommended retransmission algorithm is RECOMMENDED now, not just an
  example. Also, reduced the number of retransmissions to three.
* Added a RECOMMENDED technique for choosing xids. Start with a random
  number when you boot and increment to reduce chances of collision.
* Added an overview section at the beginning and a section with
  definitions of terms.
* Removed the requirement that a multicast REQUEST MUST have the same
  xid as the multicast DISCOVER that it is following up on.
* When using the Feature List option, servers now use the required
  list to indicate which features were implemented in processing this
  message. The supported list indicates which features the server
  supports (as before).