kiessig@mordor.s1.gov (Rick Kiessig) (04/21/87)
Has anyone heard of a device which might be used to allow two remote ethernets to talk to one another? About all I can think of is using serial lines. Is there anything better? The LANs are about 50 miles apart, separated by hills. Thanks, Rick
scarter@caip.RUTGERS.EDU (Stephen M. Carter) (04/22/87)
In article <7381@mordor.s1.gov> kiessig@mordor.s1.gov (Rick Kiessig) writes: >Has anyone heard of a device which might be used to allow two >remote ethernets to talk to one another? About all I can think >of is using serial lines. Is there anything better? The LANs >are about 50 miles apart, separated by hills. Thanks, We use T1. Other choices are 9.6-56kb line(s). Contact Cisco or Bridge (or us) for more info. We use cisco gateways for our T1 connections.
howard@COS.COM (Howard C. Berkowitz) (04/22/87)
In article <7381@mordor.s1.gov>, kiessig@mordor.s1.gov (Rick Kiessig) writes: > Has anyone heard of a device which might be used to allow two > remote ethernets to talk to one another? About all I can think > of is using serial lines. Is there anything better? The LANs > are about 50 miles apart, separated by hills. Thanks, There are two basic approaches, depending on your performance needs, budget, and protocols used. The first is a MAC-layer bridge, which recognizes Ethernet frames not on the local LAN and sends them, via hopefully high-speed lines, to the other LAN. Bridges are transparent to protocols above the link control layer. For performance to be anywhere near transparent, you would want at least 56 KBPS on a lightly loaded LAN and 1 MBPS or more on a heavily loaded one. Vitalink is a major manufacturer of long-haul (i.e., where you can't run cable or fiber between the bridges of each LAN); there are others (e.g., DEC) for cases where you can run your own facilities. Routers are more intelligent than bridges, and might give better utilization of lower-speed lines. They are not transparent to network-layer protocols such as OSI Internet, DDN IP, DECnet routing layer, etc. I suspect your major constraint will be the speed of the line you can get and afford. 56 KBPS is available on DDS, and in some areas as switched digital service on an as-needed basis. For DS1 channels at 1.544 MBPS, you can get T1 carrier from telephone companies (or build them yourself), possibly get CATV-based data if your areas are served by a single cable TV firm, use satellite (probably overkill), or, if you can get rights-of-way and can maintain it, a free-space microwave or laser link.
bsteve@gorgo.UUCP (04/22/87)
kiessig@mordor writes: >Has anyone heard of a device which might be used to allow two >remote ethernets to talk to one another? About all I can think >of is using serial lines. Is there anything better? The LANs >are about 50 miles apart, separated by hills. There is an ethernet bridge for the AT&T ISN that allows up to 1000 miles between bridged ethernets. It can be bridged via 56Kb digital service, though T-1 is preferable, and microwave T-1 is most preferable. Steve Blasingame (Oklahoma City) ihnp4!gorgo!bsteve
phil@amdcad.UUCP (04/23/87)
In article <4192@caip.RUTGERS.EDU> scarter@caip.rutgers.edu (Stephen M. Carter) writes: -In article <7381@mordor.s1.gov> kiessig@mordor.s1.gov (Rick Kiessig) writes: ->Has anyone heard of a device which might be used to allow two ->remote ethernets to talk to one another? About all I can think ->of is using serial lines. Is there anything better? The LANs ->are about 50 miles apart, separated by hills. Thanks, - -We use T1. Other choices are 9.6-56kb line(s). Contact Cisco or Bridge -(or us) for more info. We use cisco gateways for our T1 connections. We bought a bunch of Bridge Comm GS-3 TCP/IP internet routers and we're sorry we did. For example, they claim to be TCP/IP but don't implement ICMP. Let's not even mention network management. Or boxes which crashed several times a day. I suggest you look at Cisco or Proteon. I also know Ungerman Bass was working on a router product, although they didn't seem to use the same words as the rest of the world, it seemed to do the things I would expect from a router. If you want a bridge (lower case b), Translan has some interesting products also. They were working on using an Amiga as a network management console. Might be fun and sexy, etc. -- Phil Ngai, {ucbvax,decwrl,allegra}!amdcad!phil or amdcad!phil@decwrl.dec.com
normt@ihlpa.UUCP (04/23/87)
> Has anyone heard of a device which might be used to allow two > remote ethernets to talk to one another? About all I can think > of is using serial lines. Is there anything better? The LANs > are about 50 miles apart, separated by hills. Thanks, > Rick There is a product available from DEC, called TransLAN (actually it is a joint product DEC and Vitalink). It supports an IEEE 802.3 connection on one side and an RS-232 or V.35 connection on the other side. They have different version that can connect to satellite or terrestrial links. (i.e. local microwave or dedicated line) The two versions I have seen operate at up to 400Kb/s and up to 2.048Mb/s. The latest DECdirect catalog does not have the price in it, and says that TransLAN is serviced and supported by Vitalink. I have not used nor know anyone using this product, but I assume other manufacturers have similar LAN to RS-232 or something bridges available. Norm Tiedemann ihnp4!ihlpa!normt AT&T Bell Labs Naperville, IL 60566
skip@ubvax.UUCP (Stayton D Addison Jr) (04/25/87)
In article <16313@amdcad.AMD.COM> phil@amdcad.UUCP (Phil Ngai) writes: > ... >Proteon. I also know Ungerman Bass was working on a router product, >although they didn't seem to use the same words as the rest of the >world, it seemed to do the things I would expect from a router. If > ... >-- >Phil Ngai, {ucbvax,decwrl,allegra}!amdcad!phil or amdcad!phil@decwrl.dec.com When I became product manager for the internetworking products at U-B, one of the first things I did (effective 1-1-87) was change the name of the software packages. They're now "Data Link Bridge" and "XNS Router". The same hardware runs both software so we still just call it the High Speed Remote Bridge. -- Skip Addison {lll-crg, decwrl, ihnp4}!amdcad!cae780!ubvax!skip or sun!amd!ubvax!skip
kwe@bu-cs.BU.EDU (kwe@buit1.bu.edu (Kent W. England)) (04/28/87)
In article <7381@mordor.s1.gov> kiessig@mordor.s1.gov (Rick Kiessig) writes: >Has anyone heard of a device which might be used to allow two >remote ethernets to talk to one another? About all I can think >of is using serial lines. Is there anything better? The LANs >are about 50 miles apart, separated by hills. Thanks, > Has anyone ever heard of Ethernet over microwave directly at 10Mbps instead of via telco standard T-1? Well, it's here. There are currently three vendors in the field, although I read recently that DEC is coming out with product (I think with Vitalink). The idea is to present an equivalent transceiver interface to a bridge or router and then interface to standard microwave gear maintaining Ethernet signaling. You do the same thing on the other end. The microwave link is the equivalent of a separate Ethernet segment (required because of timing considerations which prevent collision enforcement across the microwave link). You can use repeaters, bridges, routers, or hosts as the system interface on each end. You cannot plug directly onto the Ethernet as with a local repeater. Following is a list of the three vendors I have discovered: Microwave Bypass, Kendall Square, Cambridge, MA 617-494-8700 LAN Connection, Lexington, MA Microwave Networks, Houston, TX If you are interested in further information, contact the vendors or send me mail and I will give you further information. Please note that I have no vested interest in these vendors or their products and that this message in not an endorsement or a solicitation for commercial gain. The cost of Ethernet over microwave is equivalent to the cost of T-1. You can still mux T-1 over the link with the Ethernet so you can also link your PBXs on the same path. Of course, the phone company does not support this service. You must own the entire route yourself, which may be a problem at 50 miles. Also note that this is 23 GHz service. This is better and easier to get for short-haul. I'm not sure about 50 miles, though. -- -------------------------------------------- | Kent W. England | | Network & Systems Engineering Group | | Boston University | | Information Technology | | 111 Cummington Street | | Boston, MA 02215 | | (617) 353-2780 | | kwe@buit1.bu.edu internet | | itkwe@bostonu BITNET | --------------------------------------------