2.2.1 Packet Header

Each packet of the WDS Multicast Application Protocol MUST specify the packet header as follows:

0	1	2	3	4	5	6	7	8	9	1 0	1	2	3	4	5	6	7	8	9	2 0	1	2	3	4	5	6	7	8	9	3 0	1
Packet-Size																OpCode								Packet-specific fields (variable)
...

Packet-Size (2 bytes): Specifies the total length of the packet in bytes.

OpCode (1 byte): A unique numeric value that is assigned to each packet of WDS Multicast Application Protocol and is used to identify the format for the rest of the packet.

Packet-specific fields (variable): Based on the OpCode field of the packet header, additional fields can be specified for each OpCode as shown in the following table:

OpCode	Meaning
WDSMC_PKTYPE_SRV_CIR 0x01	Section 2.2.2
WDSMC_PKTYPE_CNT_CIR 0x02	Section 2.2.3
WDSMC_PKTYPE_SRV_DATA 0x03	Section 2.2.4
WDSMC_PKTYPE_CNT_PROGRESS 0x04	Section 2.2.5