When the subjectAltName extension contains an IPAddress, the address MUST be stored in the octet string in "network byte order", as specified in RFC 791. The least significant bit (LSB) of each octet is the LSB of the corresponding byte in the network address. For IP version 4, as specified in RFC 791, the octet string MUST contain exactly four octets. For IP version 6, as specified in RFC 2460, the octet string MUST contain exactly sixteen octets.