3com.com was indeed illegal initially. We (the UUCP Zone) went to 
register it with the NIC and were told leading zeros weren't allowed, 
because some code might think a leading digit meant an IP address. I 
pushed back, they relented, and it was registered without a problem.

On 3/11/21 1:08 PM, Ron Natalie wrote:
> The "name" in this context the host/network/gateway name such as 
> SRI-NIC.ARPA.    3COM.COM would not have been legal back then.
> Nowhere does it imply that any of the other fields are so restricted.
>
> ------ Original Message ------
> From: "Bakul Shah" <bakul@iitbombay.org <mailto:bakul@iitbombay.org>>
> To: "Ron Natalie" <ron@ronnatalie.com <mailto:ron@ronnatalie.com>>
> Cc: "The Unix Heritage Society" <tuhs@minnie.tuhs.org 
> <mailto:tuhs@minnie.tuhs.org>>; "Internet History" 
> <internet-history@postel.org <mailto:internet-history@postel.org>>
> Sent: 3/11/2021 4:02:50 PM
> Subject: Re: [TUHS] [COFF] Pondering the hosts file
>
>> On Mar 11, 2021, at 12:32 PM, Ron Natalie <ron@ronnatalie.com 
>> <mailto:ron@ronnatalie.com>> wrote:
>>>
>>> Amusingly one day we got an Imagen ethernet-connected laser 
>>> printer.    Mike Muuss decided the thing should be named BRL-ZAP and 
>>> since I didn't know what to put down as the machine type, and it did 
>>> have a 68000 in it, I had Jake put 68000 in the entry in the host table.
>>>
>>> The next day I got all kinds of hate mail from other BSD sites who 
>>> assumed I had intentionally sabotaged the host table.  Apparently, 
>>> the BSD systems used a YACC grammar to parse the NIC table into the 
>>> Berkeley one.   The only problem is they got the grammar wrong and 
>>> assumed the CPU type always began with a letter.    There parse blew 
>>> up on my "ZAP" host and they assumed that was the desired effect.
>>
>> This is understandable as
>> a) All the "official machine names" in various assigned numbers RFCs 
>> start with a letter.
>> b) the BNF syntax for the "host table specification" entries in RFC 
>> 952 or 810 are not precise enough.
>>
>>     <cputype> ::= PDP-11/70 | DEC-1080 | C/30 | CDC-6400...etc.
>>
>>     NOTE:  See "Assigned Numbers" for specific options and acronyms
>>               for machine types, operating systems, and protocol/services.
>>
>>               for machine types, operating systems, and protocol/services.
>>
>> c) 68000 was not an official name!
>> :-) :-) :-)
>>
>>> I countered back that using a YACC grammar for this was rediculous. 
>>>  There was already a real popular file on UNIX that had a bunch of 
>>> fields separated by colons and commas (/etc/passwd anybody) that it 
>>> was never necessary to use YACC to parse.
>>
>> Can't argue with that! Though that doesn't mean a handwritten parser 
>> wouldn't have complained about 68000.
>>