IBM 9077 manual Some parts in need to be explained

If the temperature exceeds 57.5 °C (137 °F), the GRF does an automatic system shutdown.

•Hot-swappable fan

For the GRF 16S model, the cooling fan can be replaced while the GRF is in operation.

•Hot-swappable adapters

There are two types of adapters on the GRF: the media adapters and the IP Switch Control Board.

The media adapters are independent of each other and can be replaced or removed without affecting any other adapter or the operation of the GRF.

However, the IP Switch Control Board is critical to the GRF. Should this board be unavailable, the router fails.

•Crosspoint switch

The crosspoint switch is a 16x16 (16Gb per second) or 4x4 (4Gb per second) crossbar switch for the GRF 16S and GRF 04S, respectively, see Figure 12 on page 27. It is the I/O path used when the media adapters need to communicate with each other.

Serial Interface

				r	QBRT	RT			r
				fe					fe
			f					f
		B	u					u
T	x						x	B
					CPU
							R
				Media Interface
					ATM OC-3c	MM
					IP/SONET OC-3c	MM

CPU

............

..........

Combus

80 Mb/s bus	User Interface
Out-of-Band

Dynamic Routing Engine (Route Manager)

Configuration/Control

16MB Rx / 16MB Tx Buffers

Speed decoupling

WAN delays

QBRT Route Table Lookup

Times range from 1-2.5 µs

On-Board Processor

IP Header Route decisions

4 Gb/s Switch

Figure 12. GRF Architecture

Some parts in Figure 12 need to be explained:

Router Node 27