Description: The type of mapping to be employed to ascertain the SNPA Address which should be used in forwarding PDUs for this Reachable Address prefix. This object follows the manualOrAutomatic behaviour. The following values of mapping type are defined:

none: The mapping is null because the neighbor SNPA is implicit by nature of the subnetwork (e.g. a point-to-point linkage).

explicit: The subnetwork addresses in the object xIsisRASNPAAddress is to be used.

extractIDI: The SNPA is embedded in the IDI of the destination NSAP Address. The mapping algorithm extracts the SNPA to be used according to the format and encoding rules of ISO8473/Add2. This SNPA extraction algorithm can be used in conjunction with Reachable Address prefixes from the X.121, F.69, E.163 and E.164 addressing subdomains.

extractDSP: All, or a suffix, of the SNPA is embedded in the DSP of the destination address. This SNPA extraction algorithm extracts the embedded subnetwork addressing information by performing a logical AND of the xIsisRASNPAMask object value with the destination address. The part of the SNPA extracted from the destination NSAP is appended to the xIsisRASNPAPrefix object value to form the next hop subnetwork addressing information.