GR2000 Installation Guide
2.3Device Configuration
All of the GR2000 models have the same architecture and share common components, including: Routing Manager (RM), Routing Processor (RP), Network Interface Unit (NIF), power supply subsystem (PS), and cabinet. In addition, the mid-range and high-end models (GR2000-6H, GR2000-10H, GR2000-20H) implement a highspeed RM–RP connection by means of the Crossbar Switch (CSW). The device components are collectively called the Basic Control Unit (BCU). A brief description of each component is given below:
Routing Manager: The RM manages the entire router and processes routing protocols. The routing processes include creation and update of routing tables and forwarding routing tables to the Routing Processor (RP). In the GR2000-2S, the Routing Manager/Processor (RMP) integrates the functions of the RM and RP. In all other models, the RM is made up of two separate units: RM-CPU and RM-IO.
Routing Processor (RP): The RP provides wire speed packet relaying in accordance with the routing table information supplied by the RM. It also performs ARP/ICMP processing, control of Network Interface Units, processing of network interface protocols (e.g., PPP, frame relay, and ATM), statistic functions, and error handling. In the GR2000-6H, GR2000-10H and GR2000-20H, an additional RP provides load balancing and faster processing speeds.
Network Interface Unit (NIF): The NIF provides Layer 1 and Layer 2 support for various interfaces. Since the NIF is separate from the RP and provides for specific interfaces, a high degree of flexibility is achieved, meeting a wide range of user needs.
Power Supply Unit (POW): The POW uses external power to generate a stable direct current for the internal units of the router. In the GR2000-4S, GR2000-6H, GR2000-10H and GR2000-20H, an additional POW provides a duplexed power supply configuration that improves the systems availability.
Crossbar Switch (CSW): The CSW provides highspeed packet transfer between the RM and RP for the following models of GR2000-6H, GR2000-10H,
GR2000-20H, GR2000-4, GR2000-10, and GR2000-20.
Basic Control Unit (BCU): In the GR2000-2S, the BCU consists of an RMP (a duplexed BCU configuration is not available). In the GR2000-4S, the BCU consists of the RM (a duplexed BCU configuration is not available). In the GR2000-6H, GR2000-10H and GR2000-20H, the BCU consists of the RM and the CSW; a duplexed BCU configuration option is available and is independent of the duplexed power supply configuration. The BCU also contains the default memory on the RM, flash memory cards, and software.
Ease of operation and maintenance is achieved by the hot-swapping capability of components. On GR2000-2S, the NIF is hot-swappable when more than one NIF is installed; on GR2000-4S and GR2000-4, the NIF and the POW are hot-swappable when more than one NIF is installed, or when the power supply is duplexed. On the rest of the models, the BCU, RP, NIF, and POW are hot-swappable when the BCU is duplexed, more than one RP is installed, more than one NIF is installed, or the power supply is duplexed.
Figure 2-26, Figure 2-27, and Figure 2-28 show the block diagrams of the GR2000 models. A brief explanation of each model follows.
2-20 | GR2K-GA-1002 |
| Rev 6.03 |
