DUMAS@SUMEX-AIM.STANFORD.EDU.UUCP (02/24/87)
Thanks to all people who took the time to answer to my request for informations on Satellite gateway. We are an educational and research institution in France, and we intend to develop a satellite gateway (based on earth ...) .Our purpose is to interconnect baseband Ethernet networks using TCP/IP, and later ISO Transport Services on top of the Tcp. The hardware, that we shall use is a French 68000 based machine with a specific bus, running Unix sys 5. We shall send later a brief description of our own developments for peoples interested by the subject. I have summarized the answers. They were very useful for us. ================================================================== Date: 29 Jan 87 10:53:46 EST (Thu) From: Robert Hinden <hinden@ccv.bbn.com> Jean-Pierre, What is a Satellite gateway? Is that a gateway that is in a Satellite? We sell,supply, and operate earth based gateways for several clients, including DARPA and DDN, which are DOD IP Internet gateway which connect to a variety of networks, including DDN (1822 and X.25), Ethernet, Satnet, Wideband, and gateway trunks. The gateway is based on the BBN Butterfly Multiprocessor. Currently we have 19 installed in locations from Calf. to Europe. We will be installing an additonal 25 in the next year or so. ==================================================================== Date: Fri, 30 Jan 87 12:19:32 MST From: haas%utah-gr@utah-cs.arpa (Walt Haas) I believe that Vitalink makes some earth stations you could use with TCP/IP. They can be reached at 1350 Charleston Rd. Mt. View, CA 94043 (415) 968-5465 ===================================================================== Date: Tue, 3 Feb 87 09:48:38 pst From: hplabs!cae780!ubvax!dcrocker@ucbvax.Berkeley.EDU (Dave Crocker) Ungermann-Bass has a collection of TCP/IP products, including intelligent PC cards and async terminal concentrators. IP Routers (gateways) are in the offing. The product line includes the ability to down-load the hardware from a network management center. This has been used over a satellite link. Dave Software Development 408-562-7678 ==================================================================== Date: Tue, 3 Feb 87 12:05:37 pst From: Robert Michaels <michaels%hplrkm@hplabs.HP.COM> Hi: I saw your message on the TCP-IP mailing list asking about experiences with satellites. We recently made use of a satellite link to connect IP networks which I think may be of interest. Our Internet: HP has built a small internet using cisco AGS gateways equipped with their 56Kbit serial interface. The network connects divisions in the bay area via HP's Bay Area Microwave network. It also ties in divisons in Oregon and Colorado via a 56kbit channels on our leased T1 lines. In Palo Alto the various buildings are interconnected via a broadband system. The Satellite Link: It was the above network we wanted to connect to the show network at the UniForum trade show in Washington DC two weeks ago. We contracted VitaLink to provide the dish and technician at the convention and used HPs own equipment here in Palo Alto. The link was 56Kbit, running on KU band. In Palo Alto we have a 3.7m dish and at the convention they used a 1.8m dish. All hardware including modems and RF amp are built by Vitalink. The modems have a simple V.35 connection - which meant all we had to do was convert the V.35 to RS232 so it could connect to the cisco AGS. The link worked very well - delay was not objectionable. The only problem we had was snow, however, VitaLink has a dial in system via land lines to their modems and was able to detect the attenuation of the signal and alert the technician to sweep out the dish. (permanent installations have shields to protect against snow and ice). About the cisco boxes: The access control features of the gateway were very useful in controlling who had access to our internet. The lack of a V.35 interface is annoying but Black Box makes a good little hack. I see this TransLAN (DEC Bridge100) thing as a major loose. At the convention we also used a 9600 baud dial up modem as a back-up if the satellite link failed. We ran both links simultaneously - something we could never do with TransLAN. Well, that's not true, we could connect both links but TransLAN would detect the a "loop" and promptly shut down one of the links. Hope this is of interest to you. Regards, Robert Michaels ================================================================ +--------------------------------------------------+ | Gerard H. Gaye | | CEN Saclay | | | | gaye@frsac11 (bitnet) | | gaye%frsac11.bitnet@wiscvm.wisc.edu (arpanet) | | | | also: dumas@sumex.stanford.edu | +--------------------------------------------------+ -------