A method and apparatus for improved inter-domain routing convergence,
include transmitting reason information associated with a route update or
withdraw. An apparatus receiving the reason information associated with
the update or withdraw uses the reason information to determine which of
its candidate routes are also affected by substantially the same event
that triggered the initial route update or withdraw and which of its
candidate routes are not affected. For example, a candidate route may be
considered to be transient if the apparatus receiving the reason
information determines from the received reason information that a
candidate route is going to be updated or withdrawn in the near future
due. A candidate route considered as a transient route is avoided being
advertised as a preferred route.