RFC 2328, "OSPF Version 2", April 1998Source of RFC: ospf (rtg)
Errata ID: 1745
Reported By: Wenhu Lu
Date Reported: 2009-03-27
Rejected by: Stewart Bryant
Date Rejected: 2012-10-26
Section Appendix E says:
In the paragraph that starts with: "The above algorithm assumes that all" The algorithm also assumes that no network exists having an address equal to another network's broadcast address.
It should say:
The algorithm also assumes that if one of the conflicting networks is of IP host mask, its LSA origination is suppressed. The choice of the suppressing algorithm again is a local decision. However, the suppressed LSA MUST be originated if the conflicting network becomes withdrawn.
The current algorithm will derive an unchanged ID
if one of the conflicting networks is of IP host mask.
This will cause problems that the algorithm try to solve.
On the other hand, the perfect algorithm for
LSID collision resolution does not exist in
that a flat address space cannot accommodate
all of the overlaid supernet/subnet IDs.
route1 - 10.0.0.0/32
route2 - 10.0.0.1/32
route3 - 10.0.0.0/31
There is no way to originate 3 LSAs with distinct LSIDs.
Thus though in majority cases, LSID collision even
with host route is resolvable, the suppressing
mechanism is still inevitable.
This text is a change that should be taken through the working group process, as it seems to modify functionality.