i was rereading Bill Manning's draft on special use netblocks and ran
across this entry of interest (i'm not sure it helps much, but it is of
some: interest):
2.1
Prefix Discussion:
0.0.0.0/8
has a number of unique properties, many of which were built into
the protocol stacks used throughout the Internet. 0.0.0.0/32 or
the all-zeros address has been used and is still recognized as
the historical broadcast address. This use or restriction is
deprecated and modern code will treat broadcast correctly as an
all-ones value within the subnet. It is fairly common
practice to use 0.0.0.0 to encode the idea of "default".
Also, many stacks will allow the system administrator to encode IP
addresses of the form 0.0.160.57, with the presumption that historical,
"natural" masks apply and so this would represent a host that carries
the local value of x.x.160.57 within the /16 net-block that is in use
on that media. These properties suggest that a prudent network
manager & system admin will treat 0.0.0.0/8 as a special use net-block.
Router and Host requirements documents and implementations treat this
range with special use constraints.
the complete draft is at
http://www.isi.edu/~bmanning/dsua.html
richard
--
Richard Welty
rwelty@??? Averill Park Networking
rwelty@??? Unix, Linux, IP Network Engineering, Security
rwelty@??? 518-573-7592
