T320 Switch Interface Boards (SIBs) Description
The Switch Interface Boards (SIBs) provide the switching function to the destination FPC (see Figure 1). The SIBs create the switch fabric for the router, providing up to a total of 385 million packets per second (Mpps) of forwarding.
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 (top to bottom).
Each Type 1 FPC and Type 2 FPC has one dedicated ASIC with five high-speed links that connect to the SIBs (one link per SIB). SIB0 acts as a backup to SIB1 and SIB2.
- Two high-speed links connect to SIB1 and SIB2.
- One high-speed link connects to SIB0.
A Type 3 FPC has two dedicated ASICs, and each ASIC has five high-speed links that connect to the SIBs. One of the three SIBs—usually SIB0—acts as a backup to the remaining two 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.
SIBs are hot-insertable and hot-removable.
Figure 1: T320 SIB
Each SIB consists of the following components:
- Switch Fabric ASICs.
- High-speed links (HSLs) to each FPC.
- Three LEDs located on the SIB faceplate that display the status of the SIB.T320 SIB LEDs describes the functions of the SIB LEDs. If all three LEDs are off, the SIB is not receiving power. The OK and FAIL LEDs are replicated on the craft interface.
- SIB online/offline button, located on the SIB faceplate.
