Hi folks: I keep getting this quesition. Imagine two segment routed network. Network 1 is 10.10.10.0/24 with one host (Host A 10.10.10.5/24) and RouterA's E0 10.10.10.1/24 RouterA's S0 interface is connected to network 10.10.20.0/24 with .1 address and RouterB's S0 interface is also connected to this network at .2 Now RouterB's E0 interface is connected to network 10.10.30.0/24 at .1 and there is a host HostB on this segment at .5 Assume both the routers have routes to all networks reachable whithin this network. HostA sends a packet to host address 11.11.30.255. What will happen? Many people I talked to say that the RouterA will drop the packet because it is addressed to a broadcast address. Well, there is no gaurantee that Router A knows that this is a broadcast address. Secondly, even if it does, would it drop the packet My understanding was that routers don't forward layer2 broadcasts. If a packet with layer three broadcast address for either a local network or remote network arrives at a router's interface the router forwards the packet either to the next hop or broadcasts it onto the local segment. Am I wrong? I tested this out on my network and the results are as follows. I pinged a broadcast address (172.16.255.255) of my local segment from my machine (172.16.3.16/16 gw:172.16.1.1) and I got a reply back. I pinged a broadcast address of a remote segment from my machine (172.18.255.255 and there is point to point serial connection between 172.16.1.1 and 172.18.1.1 and statich routes configured between the two networks) I got reply back. I traced a route to the remote network broadcast address (172.18.255.255) from machine (172.16.3.16/16)and the packet is forwarded by 172.16.1.1 to 172.18.255.255 and the trace stopped there. My conclusion was since Layer3 broadcasts are considered as directed broadcasts, any node on the segment can reply to the packet and in this case the first node to listen to this being the remote router it sends a reply back. Please comment. Thank you Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=9699&t=9699 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
