8.4 Jitter Attenuator Daughter Card (JADC) ................... 141
8.5 Passive Port Technology ............................ 142
8.6 Active Port Technology ............................. 142
8.6.1 Per-Port Switching on the Active Modules ............... 143
8.6.2 Static Switch on the Per-Port Switching Modules ........... 145
8.7 Signal Flow on the 8260 Token-Ring Modules ................ 148
8.8 Speed Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
8.8.1 Speed Detection on Active Modules ................... 149
8.8.2 Speed Detection on Passive Modules .................. 149
8.9 Beacon Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
8.9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
8.9.2 Beacon Recovery in the 8250 ....................... 151
8.9.3 Beacon Recovery in the 8260 ....................... 155
8.9.4 Beacon Recovery on the Module Switching Modules ......... 158
8.9.5 Beacon Recovery on the Per-port Switching Modules ........ 159
8.10 Address-to-Port Mapping for Module Switching Modules ........ 160
8.11 Address-to-Port Mapping for Per-Port Switching Modules ........ 164
8.12 IEEE 802.5C Recommended Practice for Dual Ring Wrapback
Reconfiguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
8.12.1 Trunk Wrapping on the Active Per-Port Switching Modules .... 168
8.12.2 Trunk Wrapping on the Active Module-Switching Modules ..... 169
8.12.3 Merge Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
8.12.4 Trunk Unwrapping on the Per-Port Switching Modules ....... 170
8.12.5 Trunk Unwrapping on the Module-Switching Modules ........ 170
Chapter 9. 8260 Token-Ring Modules ....................... 173
9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
9.2 Configuring Token-Ring Network Parameters ................ 173
9.3 8260 18-Port Active Per-Port Switching Module ............... 174
9.3.1 Configuring the 18-Port Active Per-Port Switching Module ...... 177
9.4 8260 18-Port Active Module Switching Module ............... 180
9.4.1 Configuring the 18-Port Active Module Switching Module ...... 180
9.5 8260 20-Port Passive Module Switching Module .............. 180
9.5.1 Configuring the 20-Port Passive Module ................ 183
9.6 8260 Dual Fiber Repeater Module ....................... 185
9.6.1 Configuring the Dual Fiber Repeater Module .............. 188
Chapter 10. 8260 RMON Support .......................... 191
10.1 RMON Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
10.1.1 Network Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
10.1.2 RMON Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
10.2 RMON Goals
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
10.2.1 Offline Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
10.2.2 Preemptive Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . 194
10.2.3 Problem Detection and Reporting .................... 194
10.2.4 Value Added Data ............................. 194
10.2.5 Multiple Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
10.3 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
10.4 Managing the Ethernet LAN Environment .................. 195
10.4.1 Managing Ethernet LANs with RMON ................. 195
10.5 Managing the Token-Ring LAN Environment ................ 201
10.5.1 Managing Token-Ring LANs with RMON ................ 201
10.6 Monitoring Functions Supported In 8260 .................. 212
10.6.1 Monitoring Functions Supported by E-MAC .............. 213
10.6.2 Monitoring Functions Supported by T-MAC .............. 214
Contents vii