Reliable communication is mission critical to Emergency and Rescue operations.

MANET technology allowing communication where fixed infrastructure is not available

is very attractive for this setting. Emergency and Rescue operations may take place in

both hostile as well as benign environment. The communication system must handle

both situations. Security attacks can be launched towards any layer of the protocol

stack. What is new with wireless ad hoc networks is the network layer routing

information as a more probable target for security attacks. A reliable network service

cannot be provided without embracing routing information security. The primary

challenge is to decide which routing information can be trusted. The answer so far is

cryptographically signed routing messages. The possession of cryptographic keys serves

as proof of trustworthiness. A proper key management service is thus a critical factor

for the success of wireless ad hoc networks.