OverviewThe Warren switch has 6 ports, and no processor. i.e. Its functions are implemented entirely in hardware. VCI remapping and VCI to route mapping are setup by sending special 'PEEK' and 'POKE' cells to the switch which cause read and write operations on the switch SRAM.
Application ExamplesHome Area Network
Desk Area Network
ATM Cell FormatHeader : GFC=0, VPI=X, VCI=1-1023 , PT=0-3, CLP=0-1. The Warren Switch handles standard ATM cells and performs VCI switching (VPI is ignored). PT is modified by EFCI marking and CLP is used for selective discard.
Options- Plastic Optical Fibre
- Power on each port
- Increased Cell Buffer
- Stackability to 12 ports
Priority and Cell BufferingEach port has a high priority output queue of 4 to 6 cells and there is a shared, central cell buffer for low priority traffic of 16 to 48 kilobytes.
The Warren ProjectThe ATM Warren switch is an experimental hardware device being developed at the University of Cambridge Computer Laboratory as part of the Warren Project. The Warren project is funded by Virata and has the aim of developing a set of low-cost ATM devices, including an ATM switch.
Pin ConnectionsRJ45 modular jack:
1 RX +
2 RX -
4 DC 0 Volts
5 DC +7.5 to 15 Volts
7 TX +
8 TX -