At 10:54 AM -0500 12/12/01, Stefan Jeglinski  imposed structure on a 
stream of electrons, yielding:
>>Thanks, I'll try 127.0.0.2-127.0.0.10.
>>
>>Any harm in using 127.0.0.1-127.0.0.255?
>
>No, except I don't think 255 (or 0) would ever be returned as an A 
>record, so make it 1-254 to be strict. Furthermore, 1 is usually 
>reserved for the loopback address, which isn't really relevant 
>unless it's a UNIX system, I think. So 1 would never be returned as 
>an A record either. I might be corrected by a more knowledgeable 
>lurker. Final answer: 2-254.

Actually, there's no reason for 255 to be knocked out. In a Class C 
range it would be, but 127/8 is in classical A space and is defined 
as an A network for loopback. Even the actual 'broadcast' address for 
this network (127.255.255.255)  isn't really special in this case 
because thre's no expectation of ever using the addresses for actual 
routing of packets: 127/8 used in DNSBL work because nothing in it is 
valid beyond a single host, and the overwhelming majority of hosts 
never use anything but 127.0.0.1 out of that range. The numbers are 
just classification names, not something that will ever encounter a 
routing algorithm.

As for 127.0.0.,1, any good TCP/IP subsystem treats that as the 
trivial loopback. Name resolution of 'localhost' to 127.0.0.1 and the 
reverse may not work on mny systems without intelligent resolution 
standards (i.e. just about anything other than Unix-ish systems, 
sadly) but that's quite different from the handling of the address, 
which MUST be treated as the trivial loopback anywhere (and is 
everywhere I know of, except for ancient Windows)
-- 
Bill Cole                                  
[EMAIL PROTECTED]


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