192.0.2.0/24 was earmarked by Jon Postel for use in documentation.
It was never to show up in a routing table as a prefix that would be forwarded.
It's useful for pictures showing "Host A sends packets to Host B" when they're both on the same network. It's not useful for illustrating how things really happen out on the Internet, particularly when errors which must be returned to the sender are involved. It's like the example.com domain, which is also set aside for document purposes. example.com is useful for illustrating high-level concepts in white papers ("your SMTP client connects to the server..."), but it is not useful for describing in detail the dozen DNS transactions that happen when sendmail delivers a message to a remote site. That requires a real domain with MX backups and real addresses and everything. The example blocks/domains are useful for what they are, but their scope of usefulness is much smaller than real blocks/domains when it comes to documenting the detailed interactions between hosts and networks on the public Internet. This thread is way OT. Private queries preferred. Thanks. -- Eric A. Hall http://www.ehsco.com/ Internet Core Protocols http://www.oreilly.com/catalog/coreprot/