Detecting Network Attachment in IPv6 Networks (DNAv6) draft-ietf-dna-protocol-05.txt

1. Detecting Network Attachment in IPv6 Networks (DNAv6)draft-ietf-dna-protocol-05.txt S. Narayanan, Ed. J. Kempf, E. Nordmark, B. Pentland, JH. Choi, G. Daley, N. Montavont, N. Moore.

2. Outline • Overview of DNA • Open Issues • Next Steps

3. Link Identification • The set of prefixes configured to be advertised on the routers of the link. • The Complete Set • The smallest prefix could be used to represent the set on the router side • A selected (Landmark) prefix could be used to represent the set on the host side

4. Router Operation • Routers listen to advertisement from other routers and create • DNARouterLearnedPrefixList • Send CompleteRA messages • Respond to Landmark questions • DNARouterList • Order RA messages based on the link-local address • Include smallest prefix in all RA messages except Landmark responses

5. Fast RA • Generate a token based on the link-local address of the routers on the link • A host token is generated using the source address of the RS message • Ranking is decided based on the XOR of the host token and the router tokens • FastRAThreshold controls the number of fast RA messages • Token bucket for rate limiting

6. DNA Host Steps • Mark all the IPv6 addresses in use as optimistic. • Set all Neighbor Cache entries for routers on its Default Router List to STALE. • Send router solicitation. (See Section 5.2.5). • Receive router advertisement (s). • Mark that router's Neighbor Cache Entry [3] as REACHABLE, or add a Neighbor Cache Entry in the REACHABLE state if one does not currently exist. • Process received router advertisement. (See Section 5.2.6). • If the link has changed Change the IP configuration parameters of the host (see Section 5.2.7). • If the link has NOT changed Restore the address configuration state of all the IPv6 addresses known to be on the link. • Update default routers list and their reachability information (see Section 5.2.6.3).

7. DNA Host: Processing RA Perform following checks one after another until a decision is made: • If DNAHostPrefixList and Prefix List in RA overlap • No link change • If RA is Complete • Link change • If RA is a DNA RA • If a DNA RA was received before the link-up event “Link Change” has occurred. • If DNAHostPrefixList is ‘Complete’ • Link Change • Wait for NumRSRAComplete RA messages to complete. • If no overlapping prefixes found • Link Change • If overlapping prefixes found • No link change

8. Open Issues • Flash renumbering • Three possible levels: • do nothing special for flash renumbering and immediate reassignment (other than telling network admin to not immediately reassign prefixes) • do something so that a host can recover, but it might take a while (e.g., 90 minutes) • handle it without any delay • Do we need all of the router configuration variables? • UnicastRAInterval • MaxUnicastRABurst • RASeparation • MulticastRADelay • FastRAThreshold

9. Open Issues (Contd.) 3. All other open issues are about readability/clarity.

10. Next steps • Need volunteers to send modified text for some sections. • 5.1.7 (Smallest prefixes) • 5.3 (Tentative Options) • ??? • Need volunteers to review the document • We would like to last-call around end of April. • ???