我看了一下G.8264中有对ESSM的一般要求，具体如下：Table 11-3 – ESMC PDU format
Octet number Size/bits Field
1-6 6 octets Destination Address = 01-80-C2-00-00-02 (hex)
7-12 6 octets Source Address
13-14 2 octets Slow Protocol Ethertype = 88-09 (hex)
15 1 octet Slow Protocol Subtype = 0A (hex)
16-18 3 octets ITU-OUI = 00-19-A7 (hex)
19-20 2 octets ITU Subtype
21 bits 7:4 (Note 1) Version
bit 3 Event flag
bits 2:0 (Note 2) Reserved
22-24 3 octets Reserved
25-1532 36-1490 octets Data and padding (See point j)
Last 4 4 octets FCS
NOTE 1 – Bit 7 is the most significant bit of octet 21. Bit 7 to bit 4 (bits 7:4) represent the
four-bit version number for the ESMC.
NOTE 2 – The three least significant bits (bits 2:0) are reserved.