Download Cabletron Systems EPIM F3 Specifications

Chapter 5
FDDI RING TOPOLOGY
DUAL RING WITHOUT TREES................................................................................. 5-1
DUAL RING WITH TREES ......................................................................................... 5-2
WRAPPED RING .......................................................................................................... 5-3
SINGLE TREE ................................................................................................................ 5-4
DUAL HOMING ........................................................................................................... 5-4
Chapter 6
FDDI RING OPERATION
STATION INITIALIZATION....................................................................................... 6-1
RING INITIALIZATION.............................................................................................. 6-4
Transmitting the First Token................................................................................. 6-6
Ring Initialization................................................................................................... 6-6
Synchronous Transmission ................................................................................... 6-7
Asynchronous Transmission ................................................................................ 6-7
Token Priorities....................................................................................................... 6-7
Restricted/Non-Restricted Token Mode ............................................................ 6-8
Ring Timing and Latency...................................................................................... 6-8
Maximum Ring Latency........................................................................................ 6-8
Total Transmission Time ....................................................................................... 6-9
Token Rotation Timer ............................................................................................ 6-9
Token Hold Timer .................................................................................................. 6-9
BASIC RING OPERATION.......................................................................................... 6-9
The Beacon Process .............................................................................................. 6-10
Frame Transmission............................................................................................. 6-10
Ring Fault Recovery ............................................................................................ 6-11
OPTICAL BYPASS SWITCH .............................................................................. 6-12
Chapter 7
BRIDGING WITH THE FDMMIM
ETHERNET FRAME TYPES........................................................................................ 7-1
Ethernet II Frame Type.......................................................................................... 7-3
Ethernet “Raw” Frame Type ................................................................................ 7-3
Ethernet 802.2 Frame Type.................................................................................... 7-4
Ethernet SNAP Frame Type.................................................................................. 7-5
FDDI FRAME TYPES.................................................................................................... 7-6
FDDI 802.2 Frame Type......................................................................................... 7-7
FDDI SNAP Frame Type ....................................................................................... 7-8
ETHERNET TO FDDI BRIDGING.............................................................................. 7-9
Ethernet II to FDDI SNAP Frame Bridging...................................................... 7-10
802.3 “Raw” Frame to FDDI MAC Frame Bridging ....................................... 7-10
802.2 Frame To FDDI 802.2 Frame Bridging .................................................... 7-10
Ethernet SNAP Frame to FDDI SNAP Frame Bridging ................................. 7-11
FDDI TO ETHERNET BRIDGING............................................................................ 7-11
Case 1.............................................................................................................. 7-12
Case 2.............................................................................................................. 7-12
Case 3.............................................................................................................. 7-12
Case 4.............................................................................................................. 7-13
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