appn Cos Tg Min Security

1.3.6.1.2.1.34.4.1.5.10.10.1.7

During route computation, APPN determines the optimum route through a network in the following steps: - obtains the required route characteristics from the COS database using the mode name specified in the session request - determines all possible combinations of transmission groups and nodes that form a route to the destination database - the actual characteristics of the Nodes and TGs in these routes are compared against the COS tables that contain the required characteristics of the session. A weight is assigned based on how well the actual characteristics meet the required characteristics. Where there is no match between actual and required characteristics, the route containing the node or TG is excluded from further computation. - Each possible route is quantified by adding the weights assigned to the node and TGs in the route. The route with the lowest weight is the one used for the session. This attribute is part of the COS tables and specifies the minimum level of security protection required for a TG to be allowed to route session traffic. The security values are architecturally defined to provide continuity across all networks. Currently, security is encoded as one of the following seven values: guardedRadiation - guarded conduit containing the transmission medium; protected against physical and radiation tapping. encrypted - link level encryption is provided guardedConduit - guarded conduit; protected against physical tapping secureConduit- secure conduit, not guarded; e.g. pressurized pipe undergroundCable - underground cable located in a secure country publicSwitchedNetwork - public switched network; secure in the sense that there is no predetermined route that traffic will take nonSecure - all else, for example satellite-connected, located in a nonsecure country.