On Wed, May 02, 2001 at 01:52:54PM +0200, Roman Drahtmueller wrote:
This is not forbidden. It's just that there's no way for some packet to get back to the sender because routers shouldn't have a route for the 192.168 network. Sometimes it happens that some router (seen it in
German
university networks sometimes) annouces a route for the private networks.
Hi!
Perhaps a little bit off-topic, but can somebody explain what happens when routes for 192.168. networks are announced?
Well it's not a much better idea than announcing a default route, at least 2 ISPs have mangaged to do this, and the result was lost traffic and their network completely saturated, so much so they couldn't even log in to their routers to fix. Generally it's very bad form to put out 'private' addresses in DNS or routing tables, announcing a route for them is likely to result in complaints. If multiple ISPs put private nets into the BGP data, they would clash, and possibly cause flapping, where changed tables are propogating to millions of routers... BGP suppresses flappers after a while, but best to avoid the whole problem, by explicitly filtering out any routes to 10. 192.168 and the class C nets. Rob