Technical Summary
OSPF-MDR is based on the
selection of a subset of MANET routers, consisting of MANET
Designated Routers (MDRs) and Backup MDRs. The MDRs form a connected
dominating set (CDS), and the MDRs and Backup MDRs together form a
biconnected CDS for robustness. This CDS is exploited in two ways.
First, to reduce flooding overhead, an optimized flooding procedure
is used in which only (Backup) MDRs flood new link state
advertisements (LSAs) back out the receiving interface; reliable
flooding is ensured by retransmitting LSAs along adjacencies.
Second, adjacencies are formed only between (Backup) MDRs and a
subset of their neighbors, allowing for much better scaling in dense
networks. The CDS is constructed using 2-hop neighbor information
provided in a Hello protocol extension. The Hello protocol is
further optimized by allowing differential Hellos that report only
changes in neighbor states. Options are specified for originating
router-LSAs that provide full or partial topology information,
allowing overhead to be reduced by advertising less topology
information.
Working Group Summary
The OSPF WG was unable to reach concensus on a single MANET OSPF
approach
and agreed to go forward with the three competing approaches as
experimental RFCs.
Document Quality
Passed review and idnits
Personnel
Dave Ward