Seagate Kinetic HDD Product Manual, Rev. B
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5.3
K
INETIC
M
ESSAGE
The syntax and encoding of Kinetic Message is defined using Google Protocol Buffers and is specified by the file
kinetic.proto. The top-level message, Message, contains three embedded messages:
1. Messagetype
2. hmacAuth
3. command
5.4
C
OMMAND
E
MBEDDED
M
ESSAGE
Command is transported as bytes for ease of calculating the HMAC.
The command bytes are interpreted by casting them as embedded message, Command, containing three embedded
messages:
1. Header – Contains metadata about type of message command, such as PUT, GET, and DELETE operations.
2. Body – Contains operation-specific information, such as key range information used for the GETKEYRANGE
operations.
3. Status – Contains information about whether an associated operation succeeded or failed.
This is shown graphically in Figure 5.4.1.
Figure 8 Command Embedded Message
As shown in Figure 5.4.1, the Header, Body, and Status messages are all members of the Command message.
