Path: utzoo!attcan!uunet!yale!husc6!bu-cs!kwe From: kwe@bu-cs.BU.EDU (kwe@bu-it.bu.edu (Kent W. England)) Newsgroups: comp.dcom.lans Subject: Re: Ethernet terminal servers Summary: You can build very big nets Message-ID: <27428@bu-cs.BU.EDU> Date: 23 Jan 89 17:35:04 GMT References: <6556@fluke.COM> <13718@cup.portal.com> <14843@oberon.USC.EDU> Reply-To: kwe@bu-it.bu.edu (Kent England) Followup-To: comp.dcom.lans Organization: Boston U. Information Technology Lines: 25 In article <14843@oberon.USC.EDU> blarson@skat.usc.edu (Bob Larson) writes: > hedrick@geneva.rutgers.edu (Charles Hedrick) writes: >>Here are some advantages and disadvantages of a terminal server >>compared with directly connected terminals and modems. > >The third alternative, of using a port selector (aka data pbx) >shouldn't be ignored. (We use micoms here at usc, mostly 6600s, >connecting over 4000 terminals and over 100 hosts.) > If you build your campus network as an internetwork (ie, IP routers, fiber backbones, etc) you can build very large "virtual dataswitches", something you can't as easily do with a port selector. If you already need an internet for ethernetted hosts, the campus "lines" for your virtual dataswitch are "free". There are many other advantages to keeping your terminal-host protocol running on the same foundation (IP) as your host-host protocol, like network management. Worldwide internet connectivity is also a "freebie", except for the router connection to the outside. In essence, telnet terminal servers are more "scaleable" than port selectors. Scaleability is becoming recognized more and more as an important aspect of communication protocols and hardware. Kent England, Boston University