This read-write 20-byte binary OCTET STRING is the local NSAP address for the connection endpoint, structured as 13 bytes of prefix, 2 bytes of Cisco ID, 1 reserved byte, 3 bytes encoding slot and port number, and a final SEL byte; on FRSM12 cards it instead follows the NSAP format required by the PNNI controller. An administrator or the PNNI/PAR controller uses this address to uniquely identify the local end of the connection within the ATM addressing scheme. For example, on a non-FRSM12 card the 3 middle bytes of frLocalNSAP would encode the specific slot and port number hosting this connection's local endpoint.