Path: utzoo!mnetor!uunet!husc6!tut.cis.ohio-state.edu!uwmcsd1!ig!agate!ucbvax!MATHOM.CISCO.COM!BILLW From: BILLW@MATHOM.CISCO.COM (William Westfield) Newsgroups: comp.protocols.tcp-ip Subject: Re: Conversion to ISO - Number of NCP Hosts Message-ID: <12384429014.6.BILLW@MATHOM.CISCO.COM> Date: 22 Mar 88 20:20:24 GMT References: Sender: usenet@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 38 Does anyone know what the difference in scale is, between these two conversions? How many NCP hosts and routers/gateways/ imps were there at the time of conversion to TCP? And how many TCP hosts and routers/gateways/imps are there now and/or will there be two years from now (assuming that to be the time of the beginning of the TCP->OSI conversion)? I still have an "I Survived the TCP Transition" button somewhere, so Ill take a shot at this... The conversion from NCP to TCP took place on 1-Jan-1983. It was about 6 months after that that most hosts could communicate with each other. As of the cut-over data, most vendor software wasn't quite ready... My March, 1982 Arpanet directory shows 96 imps, and about 300 hosts. (And there were more DEC-20s than there were vaxen.) NCP didn't incorporate ideas like "routers" or "internet". There was just the ARPAnet. If you had a local area network, it was probably a Xerox "experimental" 3Mb ethernet, and it probably spoke PUP protocols. The current NIC host table has 854 Networks, 456 gateways (routers), and 5719 hosts in it. This, of course, does not include isolated places that have set up IP networks without being assigned network numbers by the NIC. It probably does not include gateways that aren't involved with talking to the arpanet. It does not include subnet gateways used within an autonomous system. It does not include hosts whose names are only obtainable only via the domain system. I think current estimates are that one new network is added to the Internet every working day (eg 250/year). Hopefully, there will be a several year period during which ISO protocols and TCP/IP will co-exist, and eventually, one of them will become unused. Bill Westfield cisco Systems. -------