3Com manual 2Bridges in the 7600 Card

Bridges in the 7600 Card 12-11

Figure 12-2Bridges in the 7600 Card

The following figure shows data-direct VCCs configured between two

7600 cards:

Cell Switching in the Bridge

Figure 12-3Virtual Circuit Connections

In fact, both Ethernet and ATM switching in the bridge are combined in a single ASIC called ZipChip. Using a technique called cell switching, all data is converted to standard sized cells. The ZipChip’s local memory is optimized for storing these data cells. The data in the memory is either converted to Ethernet frames when transmitted on the Ethernet port or to ATM/LAN Emulation frames when transmitted on a VCC. The cell data need never be copied as it is merely converted to the appropriate format by the ZipChip on its way in and out of memory.