The NSAP RRs require the following RDATA fields:

• <length> (an unsigned 16 bit integer that specifies the length in octets of the RDATA field)
• <NSAP-address> (a variable length string of octets containing the NSAP, the value is the binary encoding of the NSAP as it would appear in the CLNP source or destination address field)

More information on the NSAP record is documented with RFC 1706.