draft-engelstad-manet-name-resolution-00.txt

IETF 57, Vienna

MANET WG meeting 16.07.2003

Paal Engelstad, Telenor R&D / UniK

Problem Statement

• Need user-friendly way to address servers on ad-hoc network– Need Name Lookup (e.g. FQDN->IP-address)

• This draft focuses on on-demand ad-hoc networks

• Assumptions– Network is without infrastructure

• DNS not appropriate

• Need something similar to LLMNR /mDNS or Node Information Queries

• Need MANET-specific solution due to multi-hop

– However, network might have external connectivity• Should solution interoperate with DNS?

NOT Integrating Lookup with Route Discovery -> 3 Broadcasts (I)

NR

NS

NameRequestor

NamereSponder

1. Name Requestor broadcasts a name resolution request

1. Name Requestor broadcasts a name resolution request2. Name reSponder Broadcasts a reply (because no return route

has been formed).

NOT Integrating Lookup with Route Discovery -> 3 Broadcasts (II)

NR

NS

NameRequestor

NamereSponder

NOT Integrating Lookup with Route Discovery -> 3 Broadcasts (III)

NR

NS

NameRequestor

NamereSponder

1. Name Requestor broadcasts a name resolution request1. Name Requestor broadcasts a name resolution request2. Name reSponder Broadcasts a reply (because no return route

has been formed).

1. Name Requestor broadcasts a name resolution request.2. Name reSponder Broadcasts a reply (because no return route

has been formed).3. Name Requestor broadcasts a RREQ to find a route to the

resolved IP-address (because no forward route has been formed).

Integrating Lookup with Route Discovery -> 1 Broadcast (I)

NR

NS

NameRequestor

NamereSponder

1. Name Requestor broadcasts a name resolution request, carried by a RREQ routing header, which forms a return unicast route.

1. Name Requestor broadcasts a name resolution request, carried by a RREQ routing header, which forms a return unicast route.

2. Name reSponder unicasts a reply back along the return route. It is carried back by a RREP routing header, which forms a forward route.

Integrating Lookup with Route Discovery -> 1 Broadcast (II)

NR

NS

NameRequestor

NamereSponder

1. Name Requestor broadcasts a name resolution request, carried by a RREQ routing header, which forms a return unicast route.

2. Name reSponder unicasts a reply back along the return route. It is carried back by a RREP routing header, which forms a forward route.

3. Name Requestor may contact the resolved IP address along the forward route.

Integrating Lookup with Route Discovery -> 1 Broadcast (III)

NR

NS

NameRequestor

NamereSponder

RREQ and RREP extension formats

• Forward Lookup (FQDN-> IP-address)– ”NREQ extension” (i.e extension to RREQs):

0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Name (FQDN) ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

– ”NREP extension” (i.e. extension to RREPs): 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Reserved | #Addrs | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : IP Address (list) : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Name (FQDN) ... +-+-+-+-+-+-+-+-+-+-+-

• In addition: Reverse lookup and SRV-like lookup successfully implemented (but not yet in draft)

Interworking with External Networks

• A MANET gateway is a MANET node that is also a router or host on an external IP network

• A MANET Gateways might proxy query to DNS on external network and inject the result back into the MANET

Future work• Response Selection Rules

– Responses from node present on MANET, prioritized over proxy- responses from gateway

– Prioritize resolved IP addresses to which the best route exists

• Caching by intermediate nodes– Intermediate nodes cache name resolution information appearing

in NREPs that they are forwarding.– Only respond with cached information when a route to the

resolved IP address is valid. • AODV: Gratuitous RREP?

– successfully implemented but not yet in the draft

• For other proposed mechanisms and details, please refer to the draftSee also: http://www.unik.no/~paalee/publications/NR_paper_for_ICC2003.pdf

http://www.unik.no/~paalee/publications/NR_paper_for_ICT2003.pdf

Questions?

Thank you for your attention!