Proceedings of the 4th Gigabit Minijam of the Corporation for National Research Initiatives, January 1994.
Abstract:
The VudBoard is a simple host interface for the DEC Turbochannel which
provides a bare minimum of functionality. On the network side of the
interface, ATM cells are read from the VuNet into small on board
FIFOs. The on-board ASIC designed by DEC provides scatter/gather DMA
capability, and transfers are made over the Turbochannel in half cell
bursts, due to the small size of the FIFOs and a bug in the ASIC.
The device driver implements one-to-one mapping between application sockets and network virtual channels. Checksums and packet reassembly and disassembly are done in software.
The interface has a daughterboard connector, for which a CRC engine is being designed. This daughterboard connector could also be used to implement VCI demultiplexing.
The talk will discuss the performance of the VudBoard DMA interface connecting the Turbochannel in an Alpha workstation to the VuNet.
