Support: End,L2
    Default: X.121         	Value: Manual or X.121

    Type of mapping used to determine the SNPA address to which a
    call should be placed for this address prefix. You can modify
    this characteristic only when the entity is disabled. If the
    circuit is a broadcast circuit, this attribute must have the
    value manual.

    manual  The mapping uses the set of addresses in the
            characteristic dte addresses or the address in the
            characteristic LAN address.

    X.121   The mapping uses the X.121 address extraction algorithm.

    This characteristic is supported only if either of the following
    conditions is satisfied:

    o  The node is a level 2 router or an end node, and the owning
       circuit's characteristic type is one of the X.25 circuit
       types; or

    o  The node is a level 2 router, the owning circuit's
       characteristic type is csma-cd, and the reachable address's
       characteristic type is outbound.

    set [node node-id] routing circuit circuit-name reachable -
        address simplename mapping manual_or_x.121

    Example:

    set routing circuit csmacd-1 reachable address to-area4 -
        mapping manual