SIB Location and Redundancy
Figure 1 shows the location of the SIBs in the M320 router, T320 router,T640 router, and T1600 router.
Figure 1: M320 Router, T320 Router, T640 Router, and T1600 Router SIB Location
Figure 2 shows the location of the SIBs in the TX Matrix and TX Matrix Plus routers.
Figure 2: TX Matrix Router and TX Matrix Plus Router SIB location
T320 Router SIBs
Three SIBs are installed in the router. The SIBs are located at the center rear of the chassis in the slots labeled SIB0 through SIB2. (See T320 Router SIBs.)
Each FPC has a dedicated ASIC with five high-speed links that connect to the SIBs. Two high-speed links connect to SIB1 and SIB2. One high-speed link connects to SIB0. SIB0 acts as a backup to SIB1 and SIB2. In the event of a complete SIB failure, SIB0 will become active. Because SIB0 has only one high-speed link to each FPC, only three links will remain active. A slight degradation in forwarding capacity may occur. When the failed SIB is replaced, it will become active and SIB0 will revert to backup. The router will regain full forwarding capacity.
T640 Router, T1600 Router, and TX Matrix Router SIBs
Five SIBs are installed in the router. The SIBs are located at the center rear of the chassis in the slots labeled SIB0 through SIB4 (top to bottom). (See T640 Router, T1600 Router, and TX Matrix Router SIBs.)
Each FPC1 and FPC2 has a dedicated ASIC with five high-speed links that connect to the SIBs (one link per SIB). An FPC3 has two dedicated ASICs, and each ASIC has five high-speed links that connect to the SIBs (a total of 10 links). One of the five SIBs—usually SIB0—acts as a backup to the remaining four SIBs. In the event of a SIB failure, the backup SIB becomes active and traffic forwarding continues without any degradation. When the failed SIB is replaced, it becomes the new backup.
The SIBs are hot-insertable and hot-removable.
TX Matrix Plus Router SIBs
In the TX Matrix Plus router, one data switching plane consists of one or two TXP-F13 SIBs connected internally through the midplane to four TXP-F2S SIBs. For the TXP-4 configuration, there are a total of five data switching planes in the routing matrix. One of the five data switching planes acts as a backup spare to the remaining data switching planes. If faults are detected in an active data switching plane, the plane is taken offline, and the backup spare plane is brought online. When a failed component is replaced and brought online, the data switching plane in which it resides becomes the new backup spare plane.
