MN63Y1208 Datasheet, PDF (40/120 Pages) Panasonic Semiconductor – Built-in 4-Kbit FeRAM non-volatile memory with fast write and low power consumption

Chapter 4 RF Communication Mode
In addition, for encrypted communication, the structure of data is also slightly different from the JISX6319-4
specification. Figure 4-12 shows the block data structure.
(1) Plaintext (unencrypted) communication treats all block data as actual data.
(2) In encrypted communication, of the number of blocks m, the first block data is IV (Initial Vector) to be used
for encryption, data from second to (m-1)th blocks are actual data, and the last block data is MAC value for
Message Authentication Code (MAC).
Size specified by the number of blocks
(1) Plaintext
(unencrypted)
communication
Data 1
Data 2
Block data
Data 3
...
Data (m-1)
Data m
Actual data
(2) Encrypted
communication
IV
Size specified by the number of blocks
Data 1
Block data
Data 2
...
Data (m-2)
MAC value
IV
Actual data
Figure 4-12 Block Data Structure
MAC value
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