-----Original Message----- From: Ray Hunter [mailto:[email protected]] Sent: Monday, October 17, 2011 12:33 PM To: Philip Homburg; Hemant Singh (shemant); Ole Troan; Brian E Carpenter Cc: IPv6 WG Mailing List Subject: Re: FW: New Version Notification for, draft-hsingh-6man-enhanced-dad-01.txt
>Would therefore humbly suggest a minimum/ default / recommendation of an >8 octet nonce option (minus the existing 16 pre-assigned bits) meaning >48 bits available for the nonce field, with the option of using longer >16 or 24 octet nonce options if an implementer feels there is higher >likelihood of encountering more than 2^24 nodes on the link (giving >respectively 16*8-16 = 112 bit nonce & 24*8-16 = 176 bit nonce) First humble apologies for suggesting the 62 bits because combined with 16 bits of the Type and Length of the Nonce Option, the option won't align on an octet boundary. As for a minimum default with an option to use 16 or 24 octets in future, sounds fine to myself and Wes. Since the number of bits for the nonce was an open question for the -01 document, we will add text in a -02 version reflecting the closure. So then it should be OK to specify the default to be 48 bits and let an implementation use higher length if the implementation wants to. Also, could folks please see section 4 of the document and see this recommendation. [In a mixed SEND environment with SEND and unsecured nodes, the lengths of the nonce used by SEND and unsecured nodes MUST be identical.] The text above is suggested in case there are sloppy implementations that may overrun a buffer parsing the nonce when working in a mixed SEND environment. Thanks, Hemant -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
