There was a question of crawler pings on another thread but it did'nt seem to answer the question (maybe I just did'nt get it.)

If I recieve a ping w/ TTL = 2 and Hops = 0

A, If firewalled, what do I do?
B, If not firewalled, do I send a pong of TTL = 7 and Hops = 0
and and braodcast this ping with TTL = ? & Hops = ? to all
other connected servants?

I guess the root of my question is: If I dec TTL & inc hops and broadcast this ping, how do the servents receiving my broadcasted (crawler)ping know its a crawler if TTL = 1 & hops = 1?