jmg@cernvax.UUCP (jmg) (11/25/86)
I am aware of many implementations offering NETBIOS to application or presentation layer, assuming that we consider NETBIOS as session layer 5. The one that I use for an MSNET implementation sits upon a level 4 Transport Protocol (ISO Class 4), but others do it differently: some seem to combine layers 3 to 5 for efficiency, others use different layered protocols. I understand that VAXmates will use DECNET Transport protocols. I also seem to remember seeing remarks about NETBIOS on top of TCP/IP. What worries me in all this is the lack of compatibility between these different implementations. I realise that where a NETBIOS implementation is a combined level 3/4/5 product, any interworking between different systems is likely to be impossible. However, if one assumes a layering, plus the possibility of gateways (e.g. at Transport Level), are the contents of a NETBIOS message/datagram sufficiently standard that two different NETBIOS implementations could understand each other. Alternatively, is there the possibility of a transportable NETBIOS package with a set of calls to Transport level which could be easily mapped onto any Transport level, or maybe directly onto Network level? To add a bit of reality, many of our PCs have 3Com Ethernet cards, sometimes for historical reasons, sometimes because they need them for particular applications. Many others have BICC cards: European (important to us) and quite performant. VAXmates will certainly arrive soon (if DEC can deliver to Europe). However, if I have some application running on top of NETBIOS (MSNET or PCNET or Tapestry or a gateway to IBM offering 3270 possibilities or a general file server) then each instance of the application would seem to be limited to one particular NETBIOS implementation. It is likely that I have demonstrated a certain amount of ignorance in this article. If the whole problem is a non-problem then I should be delighted to be so told; if not then tell me how to solve it?