90 likes | 395 Views
Ad Hoc IP Address Autoconfiguration. draft-jeong-adhoc-ip-addr-autoconf-00.txt. Jaehoon Paul Jeong ETRI paul@etri.re.kr http://www.adhoc.6ants.net/~paul/ 16 th July 2003 57th IETF – Vienna, Austria. Motivation of the Draft.
E N D
Ad Hoc IP Address Autoconfiguration draft-jeong-adhoc-ip-addr-autoconf-00.txt Jaehoon Paul Jeong ETRI paul@etri.re.kr http://www.adhoc.6ants.net/~paul/ 16th July 2003 57th IETF – Vienna, Austria IETF57 MANET WG
Motivation of the Draft • 4 basic MANET unicast routing protocols will be published as experimental RFC soon. • AODV, DSR, OLSR and TBRPF • Next step? • Addressing is as essential as Routing • Automatic IP address configuration is necessary in MANET, which has dynamic topology. • Various approaches have been suggested in research domain • Stateless vs. Stateful approaches • Strong DAD vs. Weak DAD • Active DAD vs. Passive DAD • Therefore, it is time to develop MANET IP Address Autoconfiguration in engineering mode. IETF57 MANET WG
Framework of the Draft • IP Address Generation • Duplicate Address Detection • Hybid scheme considering MANET partition • Strong DAD • Weak DAD 3. Maintenance of Upper-layer Sessions IETF57 MANET WG
IP Address Generation • Selection of Random IP Address • IPv4 • IPV4_MANET_PREFIX + 16-bit Random Number • 169.254/16 is used as IPV4_MANET_PREFIX. • IPv6 • IPV6_MANET_PREFIX + 64-bit Random Number • fec0:0:0:ffff::/64 is used as IPV6_MANET_PREFIX. • Because of the deprecation of IPv6 site-local address, a new local prefix for local networks separated from the Internet is necessary. IETF57 MANET WG
Duplicate Address Detection • Phase 1 : Strong DAD • Time-based DAD • For detecting IP address duplication in a connected MANET partition within a finite bounded time interval • Strong DAD is performed during the initiation of node’s network interface. • Phase 2 : Weak DAD • Routing-based DAD • For detecting IP address duplication during ad hoc routing • It can handle the address duplication by MANET partition and mergence. • Key is used for the purpose of detecting duplicate IP addresses. • Virtual IP Address = IP Address + Key IETF57 MANET WG
Process of Duplicate Address during Weak DAD • Each node investigates the virtual IP address contained in ad hoc routing control packet • to see if there is the same address with different key in routing table or cache. • If there is the duplicate IP address, • The node sends an AERR (Address Error) message to another node using duplicate address that is associated with a different key. • The node, receiving the AERR message, auto-configures a new IP address • through Strong DAD IETF57 MANET WG
Maintenance of Upper-layer Sessions • Consequence of Address Replacement • When address duplication happens and the duplicate address is replaced with another, the sessions above network layer can be broken. • There should be a mechanism to guarantee the survivability of upper-layer sessions • Announcement of address change to peer-nodes is needed. • It is performed through AERR message. IETF57 MANET WG
Data Delivery after resolving Address Duplication • Data Delivery through IP Tunneling • After receiving the AERR message, the peer node sends its data packets to the node, having announced address change, through IP tunneling. Data Packet Peer NodeAddress : IPpn Announced NodeNew Address : IPnewOld Address : IPold SRC Addr : IPpnDEST Addr : IPnew Outer IP Header SRC Addr : IPpnDEST Addr : IPold Inner IP Header Payload IETF57 MANET WG
Discussion • This draft can include Passive DAD (PDAD). • PDAD does not need key unlike Weak DAD • It is the work of Kilian Weniger. • How about MANET wg draft? • In order to develop a MANET IP Address Autoconfiguration • Any questions or comments? IETF57 MANET WG