RFC 4251: Section 5 A string containing a comma-separated list of names. A name-list is represented as a uint32 containing its length (number of bytes that follow) followed by a comma-separated list of zero or more names. A name MUST have a non-zero length, and it MUST NOT contain a comma (","). As this is a list of names, all of the elements contained are names and MUST be in US-ASCII. Context may impose additional restrictions on the names. For example, the names in a name-list may have to be a list of valid algorithm identifiers (see Section 6 below), or a list of [RFC3066] language tags. The order of the names in a name-list may or may not be significant. Again, this depends on the context in which the list is used. Terminating null characters MUST NOT be used, neither for the individual names, nor for the list as a whole. Examples: value representation (hex) ----- -------------------- (), the empty name-list 00 00 00 00 ("zlib") 00 00 00 04 7a 6c 69 62 ("zlib,none") 00 00 00 09 7a 6c 69 62 2c 6e 6f 6e