OSI/MHS Configuration and Management Manual

Routing in OSI/MHS
OSI/MHS Configuration and Management Manual—424827-003
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Trace Information and Internal Trace Handling
Trace Information and Internal Trace Handling
OSI/MHS handles external and internal trace information as described in the 1988
X.400 recommendations (Blue Book, Recommendation X.411).
Internal trace information is added to a message every time a route retry is attempted.
This action results in an increase in the size of the message with successive retries.
The amount of the increase is modest and will not cause a resource shortage unless
serious congestion results in a large number of retries.
Loop Suppression
OSI/MHS handles loop suppression within a domain and between domains as
described in the NIST Stable Implementation Agreements for OSI, Part 8. Specifically,
OSI/MHS supports the recommended mapping between 1984 and 1988 versions of
the internal trace information, to permit the detection of routing loops in mixed-version
networks.
Partially and Fully Wild-Carded O/R Names
OSI/MHS can route messages to routes or users whose terminal address or numeric
user identifier has been partially or fully wild-carded. OSI/MHS searches for wild-
carded names if no precise, specific match can be found. It directs messages to these
routes rather than using general or catch-all routes, or overspecified or underspecified
names as described in Underspecified and Overspecified O/R Names.
Partial wild-carding means that part of the name is supplied but the rest of the name is
represented by a trailing asterisk (*). For example, if a message is being routed to a
recipient at network address 4938541 and no specific route is found, OSI/MHS checks
the partially wild-carded O/R addresses. If there is a partial route defined for network
address 493, and the other O/R elements for that recipient match (country, ADMD, and
so on), the message can be routed.
Full wild-carding means that a double asterisk (**) replaces the entire network address
or numeric user identifier. Any legitimate network address or numeric user identifier in
an incoming message is accepted as a match. If the remaining route O/R attributes
match those specified in the message, the message can be routed to the wild-carded
address.
Only network addresses and numeric user identifiers can be wild-carded, and only one
of those elements at a time can be wildcarded within a given ROUTE or APPL object.
Underspecified and Overspecified O/R Names
OSI/MHS handles underspecified and overspecified O/R names as described in the
NIST Stable Implementation Agreements for OSI, Part 8.