Hitachi GR2000 Series, Руководство по установке

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Product Overview
GR2K-GA-1002 2-31
Rev 6.03
2.4.2.5 Crossbar Switch (CSW)
The CSW provides highspeed packet transfer between the RM and the RP on the
models of GR2000-6H, GR2000-10H and GR2000-20H.
On GR2000-6H, the CSW is included in the RM-CPU board. Its 3-by-3 crossbar
switch performs highspeed packet transfer between RM and up to 3 RPs.
On GR2000-10H, the CSW is included in the RM-CPU board. Its 6-by-6 crossbar
switch performs highspeed packet transfer between RM and up to 5 RPs.
On GR2000-20H, the CSW is implemented as two separate boards (CSWM and
CSWS), one acting as backup. Its 11-by-11 crossbar switch performs highspeed
packet transfer between RM and up to 10 RPs.
2.4.3 Routing Processor Module(RP)
The RP uses the routing table from the RP to perform packet relay, ARP and ICMP
processing, NIF control, protocol handling on the data link layers (for PPP, frame
relay, and ATM), statistics, and fault handling, etc. The GR2000-6H, GR2000-10H,
and GR2000-20H use the load distribution method to allow the use of more than one
RP simultaneously.
The RP contains a packet forwarding engine (implemented by an ASIC), a routing/
QoS and filtering table lookup engine (implemented by an ASIC) that performs
hardware-based routing table lookup, and a filtering table and QoS table lookup.
This hardware-based method allows faster IP forwarding and QoS services.
The RP uses software for network layer handling (for PPP, frame relay, ATM, etc.),
IPX, packet relay on bridges, statistics, and fault handling.
The RP has two types of RPs: RP-A1 and RP-D for low to high-speed line control and
RP-C for ultrahigh-speed line control. Table 2-4 shows the specifications for each
RP.
The GR2000-2S contains an RP-A1 equivalent.