gary@ACC-SB-UNIX.ARPA.UUCP (05/16/87)
Heinz, For connecting 3B2/400's to either a serial line or an X.25 network using TCP/IP protocols you can purchase a board developed by ACC for AT&T which provides both the capability of supporting point-to-point X.25 as well access to an X.25 style network. The board, termed the ACP 2250, is based on a 10 Mhz CMOS 68000 controller and uses the Motorola 68605 X.25 Level 2 chip to support data rates in excess of 64Kbps. The board interfaces directly to the 3B2 Input/Output bus and as such will work with all 3B processors. Additional capabilities include, support for 64 SVC's, DTE/DCE programmable, internal/external programmable clocks and baud rates. Electrical interface support for RS232 or RS422/449. The ACP 2250 has been integrated with AT&T's Streams-based TCP/IP product, WIN/3B (Release 2.0) under Unix System V Release 3. The board is an exclusive product from AT&T and is available from them; however you may contact me directly for detailed technical information. In terms of Ethernet, AT&T has a product called 3Bnet. The hardware portion of the product, ie the hardware interface to the Ethernet has been integrated in to the aforementioned TCP/IP software package. Finally, AT&T's "Cheapernet" is called Starlan. And as of this writing I am not aware of an ability of supporting TCP/IP over that net. What AT&T is recommending is the use of their ISN as a bridge from a Starlan network to an Ethernet running TCP/IP and then out an X.25 line via the 2250. I hope that helps. Gary