Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site ucbvax.BERKELEY.EDU Path: utzoo!decvax!decwrl!ucbvax!laser-lovers From: GEOF@MIT-XX.ARPA (Geoffrey H. Cooper) Newsgroups: mod.computers.laser-printers Subject: Re: Survey results, part two Message-ID: <12173909569.25.GEOF@XX.LCS.MIT.EDU> Date: Thu, 9-Jan-86 13:42:33 EST Article-I.D.: XX.12173909569.25.GEOF Posted: Thu Jan 9 13:42:33 1986 Date-Received: Fri, 10-Jan-86 01:55:04 EST References: Sender: daemon@ucbvax.BERKELEY.EDU Reply-To: "imagen!geof"@decwrl Organization: The ARPA Internet Lines: 64 Approved: laser-lovers@washington.arpa > So I ask you again: > > Do you have your printers on Ethernet? If so, why? What problems > have you had? Are you generally satisfied with your setup? What > would make you switch? Well, you might consider me a biased opinion, since I wrote the TCP-IP option that Imagen sells. I'm not trying to make a sales pitch, but I have thought about the problem somewhat, and there are basically two reasons why a networked printer might be worthwhile: speed, and distributed printing. [Also, a distributed printer is easily shared among many hosts in the internet. I won't consider this as a factor since most sites have some other mechanism of acheiving this goal, such as the 4.2 spooling scheme. Note, however, that each of these schemes places more of a burden on host processing than distributing the printer.] At least in Imagen's case, you can get the same speed out of a parallel interface as you can out of a TCP connection (assuming that the host can push byte-by-byte data that fast, some can't). But a parallel interface ties the printer down to being close to the host. At most sites, there is some desire to get the printers -- especially quiet ones like the LBP-CX -- out where the users are. This desire is especially prevalent at sites where an ethernet is present. The other alternative is to use a serial line. With an Imagen, running the serial packet protocol, you can get 14-15 kilobits/second across a 19.2Kbaud serial connection (remember that there are 10 baud per byte in this case). The Imagen TCP option is not blindingly fast, as ethernet datarates go, but it does get 60-70kb/s, or 4-5 times the speed of the serial option (most serial printers run at 9600 baud so the gulf is really greater). Also, Ethernets and Internets move data quite a bit further than do serial lines. We have one customer site where the local printer routinely receives files from an arpanet site 1500 miles away, which is accessed by local users over the arpanet. The benefit of a networked option must be traded off against its cost. The option costs an extra $3K, and you have to supply a transceiver. Ask yourself: - Do I need the speed? The answer is yes if you do a lot of graphics work, and YES if you do screen dumps or other bitmaps. - Do I get real benefit from having the printer be physically distant from the host? If the host is in a machine room, the answer is probably yes. If the host is on a different floor from the users, consider the impact on elevator usage. Finally, depending on the model printer you have, decide whether there is a reasonable public area where the printer won't bother anyone. - Do I already use Ethernet? If not, then consider the extra cost of buying and running the cable. In this case, I don't think that the option makes much sense, unless you have an absolute need for the extra distance Ethernet provides. If you answered Yes to all the above, then you would probably benefit from an Ethernet printer. If you need the speed but not the distance, investigate parallel. If you need the distance but not the speed, try serial. Note that you can buy a serial printer and upgrade it to Ethernet later if your needs change. - Geof Cooper IMAGEN Corporation -------