| 摘要 |
A system and method for authenticating and encrypting messages for secure transmission is disclosed. A frame to be transmitted between devices comprises a frame header and a frame body. The frame body includes a security sequence number (SSN), frame payload, and message integrity code (MIC). The SSN is incremented by one for each frame transmitted using a same pairwise temporal key (PTK). A nonce is formed using the frame header and the SSN. Counter blocks Ctri and a first input block B0 are created using the nonce. Payload blocks Bi are created from the frame payload. The frame payload encrypted by sequentially applying the blocks of payload data Bi and corresponding counter blocks Ctri to a cipher function. The MIC is computed by cipher block chaining a cipher function applied to blocks B0 and Bi, and counter block Ctr0. The cipher functions all use the PTK.
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