Basic MAD Contents

Table 28-1 on page 783 illustrates the basic format of a MAD. The first six dwords (24 bytes) are referred to as the base-MAD header and is the same for all MADs. The fields of the base MAD header are defined in Table 28-2 on page 783.

Table 28-1. Base MAD Format
Dword Byte 0Byte 1Byte 2Byte 3
0Base MAD HeaderBase Version = 01hManagement Class (see Table 28-3 on page 785)Class Version = 01hRMethod (see Table 28-4 on page 786)
1Status (see Table 27-2 on page 776)Only used in directed-route SMP (see Table 28-6 on page 789)
2Transaction ID
3
4AttributeIDReserved
5AttributeModifier
6–63 Data field. Contents is defined by the type of MAD.
Table 28-2. Definition of Base MAD Header Fields
FieldLength (in bits)Description
Base Version8Version ...

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