Determining the IP address of neighbors in a wireless mesh

I am attempting to create a program for a wireless mesh (adhoc in all but name). Most of the network will deal with TCP messaging but to determine all neighbor IPs (as they will be unknown on startup), I choose to use UDP Broadcast for the initial discovery messages.

I have two problems currently. First, the UDP Broadcast is only being received by the sender and none of its neighbors; second, as the receiving socket can not accept the sender's socket (开发者_JAVA技巧due to the message being a datagram), I am not able to recover an IP address.

I am in need of a methodology that would allow this to work.

You're supposed to get the source address along with the datagram via e.g. recvfrom. Here's the .NET version. You also have to set a socket option to send broadcast datagrams.

See also this question: Broadcasting UDP thru all network cards

Why UDP and why not say, ICMP Pings to the broadcast address, or even bruteforcing your way down the netblock with ICMP pings? It seems to me that a ping would be more appropriate for determining if a specific host is "alive", no?