satam@jambo.ecs.umass.edu (Kirtikumar Satam) (10/02/90)
Hi! I am a graduate student of University of Massachusetts and I need to write (or to specify) protocols for a network architecture using one of the formal protocol specification language. Now, as I understand, there are three FDTs standardised in the world. Estelle and LOTOS by ISO and SDL by CCITT. Unfortunately, I could not get any actual material on it. The only discussion on the above topic that I could find was "IFIP workshops on Protocol Specification, testing and Verification". I also don't have any DPs from ISO on Estelle (DP 9074) and LOTOS (DP 8807) as well as SDL ( Z.100, I think) as of now. I need to first understand the differences between these three and also need to know which will emerge as the "Specification Language" in the future. I also might need to develop a translator for the FDT chosen for simulating the specifications on computer. Thus, I would appreciate all pointers to books, papers, publications personal experiences which will help me in my work. This being a crucial part of my thesis, any help from you will go a long way in helping me. I would appreciate personal e-mails, but if it contributes to a lively discussion on net, please post it on net too so that more people will able to express their opinions and experiences. -satam. ------------------------------------------------------------------------------ Kirtikumar Ghanashyam Satam INTERNET : satam@jambo.ecs.umass.edu BITNET : satam@umaecs.bitnet HOME : #68, Colonial Village, Amherst, MA 01002. TEL: 413-253-0954. SCHOOL : #114, Marcus Hall, Dept. of ECE, UMASS, Amherst, MA 01003. ------------------------------------------------------------------------------
gram@uctcs.uucp (Graham Wheeler) (10/04/90)
Just a brief comment - Estelle (Extended State Transition Language) is a Pascal superset allowing asynchronous concurrent execution of FSM-based processes communicating via message passing. It is an implementation-oriented FDT. Lotos is based on Petri-nets, as far as I can recall. It is much more `academic' than Estelle. I heard (second-hand) that Dave Parnas said (at the 2nd International Conference on FDT's in Canada late last year) that Lotos was popular because it had a lot of scope for making little extensions and modifications and getting publications as a result. Real protocol developers use Estelle (if they use any FDT). Just my two cents worth... Graham Wheeler | "Don't bother me, Data Network Architectures Lab| I'm reading a `Crisis'!" Dept. of Computer Science | Internet: <gram.uctcs@f4.n494.z5.fidonet.org> University of Cape Town | BANG: <...uunet!ddsw1!olsa99!uctcs!gram>
John.DeCarlo@p109.f131.n109.z1.fidonet.org (John DeCarlo) (10/05/90)
writes:
KS>I am a graduate student of University of Massachusetts and I need to
KS>write (or to specify) protocols for a network architecture using one of
KS>the formal protocol specification language.
KS> Thus, I would appreciate all pointers to books, papers,publications
KS>personal experiences which will help me in my work. This being a crucial
KS>part of my thesis, any help from you will go a long way in helping me.
Well, there is an annual conference dedicated to formal specifications, called
FORTE (FORTE '90 was in Vancouver). The proceedings from this conference would
undoubtedly prove useful.
NIST is doing a fair amount of work in Estelle. Most of the LOTOS work I know
of is being done in Europe and most of that is being done in the academic
community. I don't know what is happening with SDL.
I am doing work in LOTOS for the Consultative Committee for Space Data Systems
(CCSDS), if any specific questions on LOTOS arise.
John "You can be formal without a black tie" DeCarlo
jdecarlo@mitre.org
--
John DeCarlo, John.DeCarlo@p109.f131.n109.z1.fidonet.org
via The Black Cat's Shack's FidoNet<->Usenet Gateway
blkcat.fidonet.org and Fidonet 1:109/401enag@ifi.uio.no (Erik Naggum) (10/07/90)
Thanks for your brief comment, Graham. May I solicit one more? How does SDL (CCITT's Specification and Description Language) fit into the Estelle/Lotos picture? -- [Erik Naggum] Naggum Software; Gaustadalleen 21; 0371 OSLO; NORWAY I disclaim, <erik@naggum.uu.no>, <enag@ifi.uio.no> therefore I post. +47-295-8622, +47-256-7822, (fax) +47-260-4427
gram@uctcs.uucp (Graham Wheeler) (10/11/90)
Hi again Erik SDL (Specification & Description Language) is also FSM based, and has both a graphic and a textual form. Probably the best would be for me to quote a few references: "SDL - CCITT Specification and Description Language", Rockstrom and Saracco, IEEE Transactions on Communications, V30N6, June 1982 "A Meta-Implementation for SNA", Pozefsky and Smith, as above (this is about IBM's FAPL) I think the above issue may also have had something on LOTOS. "Specifications of a Simplified Transport Protocol using different Formal Description Techniques", Gregor Bochmann, Computer Networks and ISDN Systems, #18, 1989/90, pp 335-377 The last is a comparison of Lotos, Estelle and SDL. Hope these will be useful. Graham Wheeler | "Don't bother me, Data Network Architectures Lab| I'm reading a `Crisis'!" Dept. of Computer Science | Internet: <gram.uctcs@f4.n494.z5.fidonet.org> University of Cape Town | BANG: <...uunet!ddsw1!olsa99!uctcs!gram>