chrisma...@belgacom.net (Chris Mason) writes: > http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/admg1a05/6.3.4 > > Table 8 has all the numbers. > > 3174 was a 3270 control unit. > > 4341 was a processor, a "mainframe".
3272 was controller for 3277 3274 was introduced as controller for 3278. besides other changes from 3272/3277 to 3274/3278, a lot of the electronics were moved out of the terminal head and back into the 3274 controller .... reducing manufacturing costs and drastically increasing communication chatter over the coax (and reducing response). we complained about the significant worse human factors characteristics for 3274 controller. eventually we got a response that 3274/3278 wasn't designed for interactive computing ... but for data entry (basically updated keypunch technology). past post with old reference to 3272/3277 & 3274/3278 comparison http://www.garlic.com/~lynn/2001m.html#19 3270 protocol 3274 was "slow" in other ways ... it had very high "channel busy" overhead doing command processing. I did a project for STL (now SVL) writting support for HYPERChannel channel extender ... allowing local 3274 controlers to moved to offsite building. As a side-effect of moving real 3274 off the channels ... being replaced with HYPERChannel boxes, significantly reducing channel busy for doing the same 3274 operations ... increased overall system thruput by 10-15%. ... misc. past posts mentioning various efforts ... some involving HYPERChannel http://www.garlic.com/~lynn/subnetwork.html#hsdt later in terminal emulation in ibm/pc ... a 3277 terminal emulation card had much better upload/download thruput compared to 3278 terminal emulation card (because of design with the electronics back in the controller ... requiring significant increase coax protocol chatter ... cutting effective upload/download thruput). some old references about terminal emulation thruput http://www.garlic.com/~lynn/2005r.html#17 Intel strikes back with a parallel x86 design http://www.garlic.com/~lynn/2007r.html#10 IBM System/3 & 3277-1 http://www.garlic.com/~lynn/2010m.html#80 3270 Emulator Software other posts with references to terminal emulation http://www.garlic.com/~lynn/subnetwork.html#terminal 4341 was "mid-range" done by endicott. some number of old emails related to 4341 http://www.garlic.com/~lynn/lhwemail.html#4341 POK was surprised that 4341 was beating 3031. in the wake of failure of FS effort, there was mad rush to get products back into 370 product pipeline ... some part of that was 303x which was largely warmed over 370; 3031 was warmed over 370/158-3. clusters of 4341s had higher thruput, were lower cost and required significant reduced physical resources compared to 3033 (there is folklore about internal dirty tricks that cut in half the allocation of critical 4341 manufacturing component) 4341 increased performance, reduced costs, reduced physical requirements ... and there was big explosion in the numbers sold. Many corporations were facing running out of physical space in datacenters ... and it was possible to place 43xx machines out in dept. supply rooms and conference rooms. Large corporations had orders for several hundred at a time that went all around the corporation ... the leading edge of the distributed computing wave. internally, so many were going into dept. conference rooms, that conference rooms started to become scarce corporate resource. the explosion in number of 43xx machines internally helped spike the number of internal network nodes: http://www.garlic.com/~lynn/subnetwork.html#internalnet hitting 1000 nodes summer of 1983 ... old reference: http://www.garlic.com/~lynn/99.html#112 list of corporate sites with new network nodes added during 1983 (very large percentage being vm/43xx machines): http://www.garlic.com/~lynn/2006k.html#8 old post with picture of 1000th node desk ornament http://www.garlic.com/~lynn/2006k.html#43 above has copy of old email on the subject http://www.garlic.com/~lynn/2006k.html#email830422 -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
