The GRF uses a crosspoint switch (see Figure 7) instead of an I/O bus to interconnect its adapters. This switch is capable of 4 or 16 Gbit/s (model dependent) and gives better performance than the MCA bus.
IP Switch Control Board |
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| Route |
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4Gb/s | Manager |
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Crosspoint |
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Switch |
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1 Gb/s to each Media Card |
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Switch Engine Interface | ||||
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Route | I/O | IP | LAN/WAN | |
Table and | Buffering | Packet | ||
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Lookup |
| Forwarding |
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LAN/WAN Interfaces |
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| Media Cards |
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Figure 7. GRF 400
In conventional routers, each packet is processed at each gateway (also called hop) along a path. The processing is done at the Layer 3 level (see Figure 8 on page 14) and requires a router’s CPU to process both the packet and the route information. Conventional routers use shared resources, which leads to congestion and poor scalability and performance.
Router Node 13
