alistair@microsoft.UUCP (Alistair BANKS) (07/31/90)
In article <japi811g3@tmsoft.uucp> mshiels@tmsoft.UUCP (Michael A. Shiels) writes: >Can one lan manager server with 2 or more cards work as a bridge between >the different networks on each card? Ie another server on card A provide >services to a work station on card B? It seems that you are talking about using the multi-network capability of LanMan (i.e. defining more than one net in the [networks] section of your lanman.ini file). If so, the answer is no. The server or workstation that defines multiple nets can talk to each of them, but resources cannot be made visible ACROSS that machine. It is theoretically possible to write a software-only bridge that would reside in a LanMan server and use the same NDIS drivers, but Microsoft has no plans to do this at present. I don't know of any 3rd party developers who are working on such a product, but it is possbile there are some. Alistair Banks OS/2 Group Microsoft
alistair@microsoft.UUCP (Alistair BANKS) (08/02/90)
In article <56187@microsoft.UUCP> alistair@microsoft.UUCP (Alistair BANKS) writes: >In article <japi811g3@tmsoft.uucp> mshiels@tmsoft.UUCP (Michael A. Shiels) writes: >>Can one lan manager server with 2 or more cards work as a bridge between ... >It is theoretically possible to write a software-only bridge that would >reside in a LanMan server and use the same NDIS drivers, but Microsoft >has no plans to do this at present. I received more flames than usual about LanMan internal bridging as part of the LanMan product, so I'm posting some extra thoughts. LAN Manager networks can be connected today by a number of 3rd party products at the BRIDGE and ROUTER level. Microsoft's own world wide LAN is a good example of this: our international subsiduaries and field offices are connected to the campus net using leased telephone lines with bridges and routers from Ungerman Bass. These devices contain both hardware and software, and they connect directly to the LAN cable. Routers (and most bridges) do provide effective network traffic isolation, yet give good performance (line speeds up to T3/20 Mbps); the technology is mature and fairly inexpensive. The disadvantage of briges and routers is that they are topology and protocol dependent; Microsoft's internal net relies on the fact that all locations are wired with Ethernet and that the protocol used when crossing routers is XNS. Leased lines can also be costly if the remote connections are needed only occasionally. Note that not all protocols support routing which is the more effective way to isolate LAN traffic. Netbeui which ships with LM 2.0 supports routing only on Token Ring; but note that Novell's IPX/SPX or 3Com's NBP do not support source level routing at all. The problems with bridges and routers can be solved in a general way only with a transport level gateway and that is our approach at present. Microsoft LanManager is a network built on an open transport interface - thus bridging & routing is left as a feature of the transport - so LanMan on TCP/IP would use TCP/IP routers, LanMan on XNS would use XNS routing. So there are many, open, solutions for LanMan, but what doesnt exist today is a Microsoft product, which lives on the Lan Manager server, which does brindging and/or routing. But then this doesnt exist for our major competitors either. Alistair Banks OS/2 Group Microsoft
jb@mytardis.UUCP (John Bartas) (08/02/90)
In article <56187@microsoft.UUCP>, alistair@microsoft.UUCP (Alistair BANKS) writes: > In article <japi811g3@tmsoft.uucp> mshiels@tmsoft.UUCP (Michael A. Shiels) writes: > >Can one lan manager server with 2 or more cards work as a bridge between > >the different networks on each card? Ie another server on card A provide > >services to a work station on card B? > > It seems that you are talking about using the multi-network capability > of LanMan (i.e. defining more than one net in the [networks] section > of your lanman.ini file). If so, the answer is no. The server or workstation > that defines multiple nets can talk to each of them, but resources cannot > be made visible ACROSS that machine. > > It is theoretically possible to write a software-only bridge that would > reside in a LanMan server and use the same NDIS drivers, but Microsoft > has no plans to do this at present. > > I don't know of any 3rd party developers who are working on such a > product, but it is possbile there are some. > > Alistair Banks > OS/2 Group > Microsoft I missed the original posting somehow, so I hope what I have to say is relevant. Both TCP/IP and OSI protocols support routing across separate nets as described. TCP/IP is available from several vendors for OS/2 now, and I suspect OSI is too. The drawback is that I don't know of any Lan Managers that are shipped with these protocols as part of the basic package. 3com has a TCP/IP product, but I *think* it costs extra. I'm sure all the others do; these companies don't like to work for free :-). Some TCP/IP products for DOS do not support routing in order to reduce the size of the TCP/IP TSR (and for a variety of other reasons). There is no reason to do this on OS/2, but you should verify that routing is supported before you spend your money. If you mail me directly,I can provide a few vendor names. -JB- ----------------------------------------------------------------------- John Bartas | "We have met the enemy, and he is us" -Pogo NetPort Software |