Hello Group, Posted this yesterday but mysteriously disappeared :-). Three things to confirm about broadcasts.
a) the all ones broadcast i.e 255.255.255.255 by default will only be propagated to the local network and is not forwarded by routers b) network and subnet directed broadcasts. If I were to broadcast to 192.168.1.255, and I have subnets 192.168.1.32/27, 192.168.1.64/27 and 192.168.1.96/27, would all the subnets receive it as well? c) referring to scenario b), I believe that broadcasts with destination 192.168.1.255 is forwarded. Is this true? I was going thru this article about the effect of using the all ones subnet. There are somethings that I'm still confused about. The link is http://www.cisco.com/warp/public/105/40.html 1. In the first example, when host 195.1.1.24 sends a local broadcast to 195.1.1.255, will hosts attached to router 2's async lines receive the broadcast? 2. OK, its a directed broadcast and router 2 looks up its routing table and forwards it out using the default route. Router 1 receives the packet. I believe the packet is forwarded out to all 192.1.1.x/26 subnets, right? Will Router 1 forward the packet back to Router 2? I hope not 2a. Another way of looking at it is router 1 thinks that it is a broadcast only for subnet 195.1.1.192 and forwards it out only to router 5. Hmmm .... I'm definitely confused 3. Router 5 receives the packet from router 1. How will it interpret the packet? I'm guessing that the router sees it as a directed broadcast and send it out via the default route. Is it normal that routers forward a packet out from an interface that it received on? As in its received on e0 and forwarded out e0 as well 4. Once router 1 receives the packet from router 5, will it forward the packet out to all 192.1.1.x/26 subnets again or just to router 5. The article did not detail this part and just specified that it will bounce between routers 1 and 5. It also says that routers 2 thru 4 see the 'broadcast' only once. The way I see it , if all subnets receive the broadcast then routers 2 thru 4 should receive the packets as many times as router 5. I would appreciate all the help I can get. I know you gurus can help me out. Thanks!! Wes Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=48570&t=48570 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]