M320 Router Major Hardware Components

Table 10 lists the T320 router major components and characteristics.

Table 10: M320 Router Major Hardware Components                    

Component	Quantity	Function	Redundant	Field- Replaceable	Offline Button
Connector Interface Panel (CIP)	1	Provides ports for external management and alarm relay devices; includes an electrostatic discharge (ESD) point	—	Hot-pluggable	—
Control Board	1-2	Monitors and controls router components (requires a Routing Engine)	Yes	Hot-pluggable (if not redundant)	Yes
Cooling system	2 front fan trays, 1 rear fan tray	Cools router components	Yes	Hot-removable, Hot insertable	—
Craft interface	1	Displays status and provides an interface for controlling router functions	—	Hot-removable. hot-insertable	—
FPC	1-8	Connects PICs to other router components, contains Packet Forwarding Engines (supports FPC1, FPC2, and FPC3)	—	Hot-removable, hot-insertable	Yes
Host subsystem	1-2	Consists of a Routing Engine and Control Board and provides routing and system management functions	Yes	Hot-pluggable	—
PIC	1-4 per FPC	Provides an interface to various network media	—	Hot-removable, hot-insertable	Yes
Power supply (DC only)	2	Distributes needed voltages to router components	Yes	Hot-removable, hot-insertable	—
Routing Engine	1-2	Provides routing functions and routing tables (requires a Control Board)	Yes	Hot-pluggable (if not redundant)	Reset button
SIB	4	Provides switching function to the destination FPC	Yes	Hot-removable, hot-insertable	Yes

Field-replaceable units (FRUs) are router components that can be replaced at the customer site. Replacing FRUs requires minimal router downtime. There are three types of FRUs:

• Hot-removable and hot-insertable—You can remove and replace the component without powering down the router or interrupting the routing functions.
• Hot-pluggable—You can remove the component without powering down the router, but routing functions are interrupted until the replacement is installed.
• Requires router shutdown—You must power down the router before removing the component.