Path: utzoo!utgpu!watserv1!watmath!att!tut.cis.ohio-state.edu!ucbvax!UMD5.UMD.EDU!stjohns
From: stjohns@UMD5.UMD.EDU ("Mike StJohns")
Newsgroups: comp.protocols.tcp-ip
Subject: Re: can anyone identify this mystery box?
Message-ID: <9101140202.AA13745@umd5.UMD.EDU>
Date: 14 Jan 91 02:02:06 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 21

>> 
>> I have come across a mystery piece of equipment manufactured by
>> "Acc", circa 1980, that looks like some kind of sophisticated modem.  
>> It is a box with four plug-in modules:  two "power modules" and two 
>> "logic modules".  Front panel says "ECU".  Lots of led's and toggle 
>> switches, plug out the back that says "to host/imp" and "comm line".  
>> A big piece of packing tape on the top says "Arpa".
>> 
>> Anyone know what this is or how to get ahold of Acc?

Jim, the box you have is an "Error Correcting Unit" one of the last of
a dying breed - donate it to your museum.  ECU's were used in the old
ARPANET and are still used in the MILNET to take an 1822Distant Host
interface and extend it over a standard bit-synchronous data stream.
The ECU's converted the 1822 control and data signals into an SDLC (I
think?) stream.

ACC is still on the net - you might check with Gary Krall
(krall@acc.com)

Mike