The layout of a UUID is as follows:
TTTL-TM-TH-RC-NNNNNN
Where:
TTTL = 4 hex octets, "time low"
TM = 2 hex octets, "time mid"
TH = 2 hex octets, "time high and version", "version" in 4 most significant bits (0001 = time-based, 0010 = DCE, 0011 = name-based/MD5, 0100 = random, 0101 = name-based/SHA-1
R = 1 hex octet, "clock seq high and reserved", "variant" in 1-3 most significant bits (0 = NCS [1-7], 10 = RFC 4122 [8-B], 110 = Microsoft [C-D], 111 = reserved [E-F])
C = 1 hex octet, "close seq low"
NNNNNN = 6 hex octets, "node"
On the wire, the bytes of a UUID are transmitted in network byte order (most significant byte first)
