Medium Access Control (MAC) and Physical Layer (PHY) - CISE

4-June-07 P1901_PRO_016_r0
the least significant. The Packet Number sent in the CCMP Header is the one correspondent to the first
packet or fragment of a packet sent in the Burst.
- Rsvd – 8 bits. Reserved bits set to 0 and ignored on reception.
- KeyID - 8 bits. 5 bits are reserved and set to 0. Bit 5 is set to 1. Bits 6–7 of the Key ID octet are for the Key
ID subfield. The Key ID subfield allows for operating with different keys.
The CCMP Header shall be the following structure:
1 byte
PN0 PN1 Rsvd KeyID PN2 PN3 PN4 PN5
Rsvd 1 KeyID
Submission page 282 UPA-OPERA
1 bit
b0 b4 b5 b6 b7
Figure 141: CCMP Header Structure
CCM requires for encryption and message integrity checking, an unique Nonce value, a number which never
repeats during a given life time, for each packet protected by a given temporal key. CCM requires a fresh temporal
key for every session.
The PN is combined with other fields to produce a 13-octet long Nonce as corresponds to setting the parameter L to
2 as indicated in IETF RFC 3610. This Nonce is represented in Figure 142.