Siemens CP 1515 User Manual
Page 189
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Industrial Ethernet Wireless LAN RLM Manager, CP 1515 Manager
C79000-G8976-C171-01
189
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Table 6 Alternative Schemes gives a scheme where at each period two keys
are in use; at the end of each period, the oldest key is no longer valid and
needs to be replaced at all stations. Advantage of this scheme versus the
scheme in
Table 5 Single Key - Transition Period
is that it requires less
frequent configuration changes at all Radio Link Modules.
Period
AP Configuration
Out-
ward
STA
Configuration(s)
In-ward
#
Description
Keys 1-2-3-4
Tx
Key
Keys 1-2-3-4 Tx
Key
0
Main life key A
A-0-0-0
1
A
A-B-C-D
1
A
1
Main life A+B
A-B-0-0
2
B
=
1|2
A | B
2
Main life B+C
0-B-C-0
3
C
=
2|3
B | C
3
Main life C+D
0-0-C-D
4
D
=
3|4
C | D
4
Main life D+E
E-0-0-D
1
E
A-B-C-D
E-F-G-H
4
1
D
E
5
Main life E+F
E-F-0-0
2
F
E-F-G-H
1|2
E | F