HP 5200zl, 3500yl manual Inside the ProVision Asic Architecture, Classification and lookup

Figure 1. ProVision ASIC Architecture for HP ProCurve Switch 5406zl

The diagram above illustrates an example of the logical interconnection of the ProVision ASICs on the 6-slot 5406zl series switch. All of the key elements are connected to the active backplane. The active backplane contains the switch fabric and distributes power to all modules. The HP ProCurve Switch 5412zl, 3548yl, 3524yl, and 6224yl have similar architectural components. The primary difference in the illustration would be the number of ports supported.

Inside the ProVision ASIC Architecture

Each line interface module contains a full ASIC-based Layer 3 routing switch engine as well as Layer 4 filtering and metering. These new ProVision ASICs are HP ProCurve’s 4th-generation switching ASICs. This network switch engine, in the ProVision ASICs, provides all the packet processing: Layer 2 and Layer 3 lookups; filtering and forwarding decisions; VLAN, trunking, and priority queuing determinations. The ProVision ASIC on each line card contains its own CPU. These features of the ProVision ASIC are common for all products in the HP ProCurve Switch 5400zl, 3500yl, and 6200yl series.

Classification and lookup

When a packet first comes in, the classifier section determines the packet characteristics, its addresses, VLAN affiliation, any priority specification, etc. The packet is stored in input memory; lookups into the table memory are done to determine routing information; and a ProVision ASIC-specific packet header is created for the packet with this information. This header is then forwarded to the Policy Enforcement Engine.

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