To introduce a transition period between the main life of the successive
keys, the scheme has to be changed as shown in Table 5 Single Key -
Transition Period.
Period
#
Description
0
Main life key A A-0-0-0
1
Transition A-B A-B-0-0
2
Main life key B 0-B-0-0
3
Transition B-C 0-B-C-0
4
Main life key C 0-0-C-0
5
Transition C-D 0-0-C-D
6
Main life key D 0-0-0-D
7
Transition D-E E-0-0-D
8
Main life key E E-0-0-0
9
Transition E-F
Notice that in the transition periods 1, 3 and 5 the end users can switch over
from one Txkey index to the next. At the end of this period, all stations must
be over to the new key index. Transition period 7 includes the transition to a
new set of keys as well. The total length of time a key is used consists here
of the main life time period and two transition periods. Assuming the main
Industrial Ethernet Wireless LAN RLM Manager, CP 1515 Manager
C79000-G8976-C171-01
AP Configuration Out-
Keys 1-2-3-4 Tx
1
2
2
3
3
4
4
1
1
E-F-0-0
2
STA Configuration(s) In-ward
ward
Key
Keys 1-2-3-4
A
A-B-C-D
B
=
B
=
C
=
C
=
D
=
D
=
E
A-B-C-DE-F-G-H 4
E
E-F-G-H
F
=
Tx
Key
1
A
1|2 A | B
2
B
2|3 B | C
3
C
3|4 C | D
4
D
D
1
E
1
E
1|2 E | F
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