5. NLRI Encoding

The Network Layer Reachability information is encoded as one or more 2-tuples of the form <length, prefix>, whose fields are described below:

                   +---------------------------+
                   |   Length (1 octet)        |
                   +---------------------------+
                   |   Prefix (variable)       |
                   +---------------------------+

The use and the meaning of these fields are as follows:

a) Length:

The Length field indicates the length, in bits, of the address prefix. A length of zero indicates a prefix that matches all (as specified by the address family) addresses (with prefix, itself, of zero octets).

b) Prefix:

The Prefix field contains an address prefix followed by enough trailing bits to make the end of the field fall on an octet boundary. Note that the value of trailing bits is irrelevant.