5.3
K
M
INETIC
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
E
OMMAND
MBEDDED
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.
As shown in Figure 5.4.1, the Header, Body, and Status messages are all members of the Command message.
Seagate Kinetic HDD Product Manual, Rev. A
M
ESSAGE
Figure 8 Command Embedded Message
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