Ran, > Proprietary is a commonly used term to describe something that does >not have a full, complete, and open specification -- which is the >current state of IS-IS. Now folks (including me) are trying to fix >that issue by publishing sundry non-standard RFCs on how the as-deployed >IS-IS really works (which effort is to be applauded). But the bottom-line >remains that *today* the as-deployed IS-IS and the documented IS-IS >aren't the same. I wish they were. I am glad to hear this activity is going on. Regarding your definition of "proprietary". From Merriam-Webster Online at http://www.m-w.com/ : Main Entry: 1pro·pri·e·tary Pronunciation: pr&-'prI-&-"ter-E Function: noun Inflected Form(s): plural -tar·ies Date: 15th century 1 : one that possesses, owns, or holds exclusive right to something; specifically : PROPRIETOR 1 2 : something that is used, produced, or marketed under exclusive legal right of the inventor or maker; specifically : a drug (as a patent medicine) that is protected by secrecy, patent, or copyright against free competition as to name, product, composition, or process of manufacture 3 : a business secretly owned by and run as a cover for an intelligence organization This matches my view that proprietary has more to do with ownership than the availability of open specifications. A protocol can have open specifications, but still be proprietary. For example prior to Sun Microsystems giving change control of NFS and RPC to the IETF, NFS and RPC had open specifications (and there were independent inter-operable implementations), but were still proprietary. IS-IS as deployed on the Internet is an interesting case. It is clearly open and is not proprietary, but as you point out there is no complete specification. I don't think we have a term for this combination :-) Regards, Bob