LYMAN_CHAPIN@ICE9.CEO.DG.COM (03/31/88)
This just in from Juha Heinanen in Finland: >> In article <8803261505.AA04812@wb6rqn.UUCP> brian@wb6rqn.UUCP (Brian Lloyd) >> writes: >> >European attendees. The consensus was that OSI really wasn't happening >> >and that they were all planning to go the TCP/IP route. I guess that >> >the ISO/OSI hard-sell has created a market that only TCP can currently >> >fill. >> >> Pretty much a correct observation. The POLITICAL plan is to go the >> connection oriented (X.25) OSI route that doesn't care about local >> area networks (it only cares about the profits of PTT monopolies). So >> if you want to build a LAN and connect it to another LAN what else >> have you got except TCP/IP? Evidently there are still people who see "OSI" and hear "X.25" and "connections". ** THIS IS NOT A VALID ASSUMPTION! ** You can have OSI with a Transport protocol similar to TCP (ISO 8073) and a connectionless internetwork protocol (ISO 8473) even more similar to IP. You do not have to have X.25. You do not have to have PTTs. You do not have to have network connections. There is NO part of OSI that requires X.25 (although if X.25 is all you have, you can use it to support OSI). OSI loves LANs. The OSI IP likes nothing better than to connect LANs together (or to any other type of subnetwork). With the ISO IP, you also get a host-gateway routing protocol (ISO 9542), and you will soon get a gateway-to-gateway routing protocol (a link state routing scheme based on DECnet Phase V routing). If you need X.25 to get across a PTT (or for any other reason), you can run ISO IP on top of it (it looks like just another point-to- point link), keeping the connectionless internet intact. ALL OF THIS IS AVAILABLE *NOW*. The Transport, Internet, and host- gateway protocol standards are done. They are not "working drafts". They are being implemented. They are already available in commercial products from at least one large computer manufacturer (DG). You can get copies of the standards from your local national standards body. In Finland, call Esko Ojanpera at (+358)-0-456 65-6. ----------------------------------------------------------------------------- Lyman Chapin lyman@ice9.ceo.dg.com Data General Corp. [lyman%ice9.ceo.dg.com@relay.cs.net] (617) 870-6056 -----------------------------------------------------------------------------
CERF@A.ISI.EDU (04/01/88)
Not to put too fine a point on it, how many different vendors have implementations which are either known to interoperate or have been through COS certification? I'm glad to know the specs are finished. I will be even more happy to know that there are implementations for many operating system and hardware bases which can work together and which you can buy off the shelf. Vint
schoff@A.NYSER.NET ("Marty Schoffstall") (04/01/88)
ALL OF THIS IS AVAILABLE *NOW*. The Transport, Internet, and host-
gateway protocol standards are done. They are not "working drafts".
They are being implemented. They are already available in commercial
products from at least one large computer manufacturer (DG). You
can get copies of the standards from your local national standards
body. In Finland, call Esko Ojanpera at (+358)-0-456 65-6.
Is it interoperable with anyone else's? Does it work in an OSI internet?
[ let's say 4 ethernets, a 802.5, and a X.25 interconnection
for simplicity sake].
Or is it the standard:
It Talks To Itself on a Single Cable
Martyjh@tut.fi (Juha Hein{nen) (04/02/88)
Evidently there are still people who see "OSI" and hear "X.25" and "connections". ** THIS IS NOT A VALID ASSUMPTION! ** You can have OSI with a Transport protocol similar to TCP (ISO 8073) and a connectionless internetwork protocol (ISO 8473) even more similar to IP. You do not have to have X.25. You do not have to have PTTs. You do not have to have network connections. There is NO part of OSI that requires X.25 (although if X.25 is all you have, you can use it to support OSI). OSI loves LANs. The OSI IP likes nothing better than to connect LANs together (or to any other type of subnetwork). ... I fully agree with all you are saying about ISO IP/TP4 supporting LANs. The problem is that according to EC politics, you are NOT allowed to run ISO IP in the European academic OSI network!!!! Instead you have to run CONS and they even force you to run X.25 on your Ethernet. This is THE European OSI. Of course we in Finland and even wider in Scandinavia don't accept this bullshit and are just now in the process to set up an Internet using multiprotocol routers that soon will support ISO IP. Because of this, the leaders of the political OSI migration are saying that we are non European heretics. Hope this clarifies my earlier comment. I have nothing against OSI but European OSI politics. Juha Heinanen
LYMAN_CHAPIN@ICE9.CEO.DG.COM (04/06/88)
>> Not to put too fine a point on it, how many different vendors have >> implementations which are either known to interoperate or have been >> through COS certification? I'm glad to know the specs are finished. >> I will be even more happy to know that there are implementations for >> many operating systems and hardware bases which can work together and >> which you can buy off the shelf. Amen! OSI has a LONG way to go before it even comes close to the level of real-product availability of TCP/IP. It would be very difficult (although not impossible) to go out into the world today & put together a fully OSI network using commercially available hardware & software. And, more to the point, there would be very little reason to go to the trouble of doing so - TCP/IP products are readily available, they do the job, and they are (after years of experience and engineering) both efficient and reliable. I am not suggesting that the moment an OSI product becomes available, it is ipso facto preferable to its TCP/IP counterpart! But sooner or later everyone (well, almost everyone) is going to have to figure out how to make OSI networks work. Unfortunately, while a few people have been working to factor the advantages of TCP/IP internetworking into OSI (via ISO TP/IP) in an effort to make OSI viable (i.e. not just X.25 and PTTs), too many other people have been just bashing it (and OSI, like most network architectures, is highly bashable), on the assumption (presumably) that they would never have to live with it. Which brings us to the current state of affairs: commercial OSI gear is X.25-based (and most of it is in Europe), because the people with a vested interest in TP/IP-based OSI haven't been working on OSI - they've been working on TCP/IP, and taking pot shots at OSI whenever possible. Perhaps OSI will fail worldwide, thereby keeping the world safe for TCP/IP. Or, perhaps OSI (based on X.25) will quickly become the norm in the rest of the world (thanks to various combinations of PTTs), while we play catch-up. I like TCP/IP a whole lot better than X.25-OSI; but I would like an internationally viable TP/IP-OSI even better. ----------------------------------------------------------------------------- Lyman Chapin lyman@ice9.ceo.dg.com Data General Corp. [lyman%ice9.ceo.dg.com@relay.cs.net] (617) 870-6056 -----------------------------------------------------------------------------
rajaei@ttds.UUCP (Hassan Rajaei) (04/08/88)
In article <76.008873@adam.DG.COM> <LYMAN_CHAPIN%ICE9.CEO.DG.COM@adam.DG.COM> writes: > >Evidently there are still people who see "OSI" and hear "X.25" and >"connections". ** THIS IS NOT A VALID ASSUMPTION! ** > >You can have OSI with a Transport protocol similar to TCP (ISO 8073) >and a connectionless internetwork protocol (ISO 8473) even more similar >to IP. You do not have to have X.25. You do not have to have PTTs. >You do not have to have network connections. There is NO part of OSI I am really glad you mentioned this. There has been a confusion between OSI model and X.25 protocol for a long time just because X.25 was the only available implementation of OSI. The OSI model is so general that you may do any thing with it (except the overhead!). If there is not an standard protocol available for your need within the model, that doesn't mean the model itself is incapabel of doing that. In spite of many standard protocols available for OSI at present time, I believe we need many new ones in future even for the low layers like physical, link and network. The existing standars for low layers are incapable of handling the ultra super speed networks of the future (FDDI can handle just 150 Mbps). The same is true with X.25 and its IP X.75 which are not only limited by speed but rather make the network very vulnerable because of their connection- oriented behaviour throughout the network (internetworks). As Lyman Chapin said the limitation is not in the model but in the protocols. There is much to be done for OSI model to be accepted (or rejected!) world wide, both with new standard protocols and implementations. Hassan Rajaei The Royal Inst. of Technology Stockholm Sweden rajaei@tds.kth.se
erik@retix.retix.COM (Erik Forsberg) (04/12/88)
In article <1157@ttds.UUCP> rajaei@ttds.UUCP (Hassan Rajaei) writes: >I am really glad you mentioned this. There has been a confusion between >OSI model and X.25 protocol for a long time just because X.25 was the only >available implementation of OSI. > >The OSI model is so general that you may do any thing with it (except the >overhead!). If there is not an standard protocol available for your need >within the model, that doesn't mean the model itself is incapabel of doing >that. In spite of many standard protocols available for OSI at present >time, I believe we need many new ones in future even for the low layers >like physical, link and network. > >The existing standars for low layers are incapable of handling the ultra >super speed networks of the future (FDDI can handle just 150 Mbps). The >same is true with X.25 and its IP X.75 which are not only limited by speed >but rather make the network very vulnerable because of their connection- >oriented behaviour throughout the network (internetworks). As Lyman Chapin >said the limitation is not in the model but in the protocols. > >There is much to be done for OSI model to be accepted (or rejected!) world >wide, both with new standard protocols and implementations. > Please make a distinction between the OSI MODEL and the protocols specified by ISO that implements services defined by the ISO model. I don't think you can do anything with the OSI model. Just because you invent your own protocol, which happens to provide some service defined by the OSI model, doesn't really make this new protocol an OSI protocol. There will be just confusion and interoperability problems if every new protocol claims to be an "OSI protocol". Before it could be considered as a protocol to be used to implement a service as defined by OSI, it should become an ISO standard. Otherwise, it's not too useful for the majority of the worlds data communications users. Anyway, there certainly is a place for new protocols for new, higher performing LAN technologies. But, even the existing ISO 8073/8473 protocol combinations are quite performing. (This is the ISO Class 4 Transport protocol operating over a connection-less network service, almost identical with DoD IP). For example, by eliminating overhead imposed by non-perfect hardware, this protocol combination has proven able to have a substained transport layer user data throughput of more than 2000 packets per second (each packet 1024 bytes) which is approximately 16 Megabits/second (this is measured on a VAX 8650). Now, if you add some well-known, supposedly reasonable Ethernet controllers on an otherwise idle Ethernet network, performance drops to a measly 60-180 packets per second, it is my opinion that controller hardware technology, computer buses and software used to interface with the host operating system needs some large improvements. I do not understand why so many believes that X.25 is the only way to implement OSI. It is certainly true that the european continent started work in ISO, specifying the Connection-oriented network service as examplified by X.25, but I think the US has been as successfull in providing equally good protocols when Local Area Networks are the primary technology of interest. Now, there are very reasonable standards in how to inter-connect multiple Local Area Networks using these venerable and perfectly working X.25's as provided by any Public Data Network service provider (in most any country of the world). One of the major problems is that there is no natural way to interoperate between networks using ISO 8473 (IP) or ISO 8208 (X.25) as the network layer. There will always be limitations when such attempts are made (there are several proposals discussed as of this time). -- ---------------------------------------------------------------------------- Erik Forsberg, Retix, 2644 30th Street, Santa Monica CA 90405 (213) 399-2200 UUCP: {cepu,ttidca,rutgers,oliveb}!retix!erik, erik@retix.com