IPv4 Multicast Security: A Network Perspective

Multicast holds great promise in reducing the network bandwidth required for simultaneous communication between multiple hosts. Documented routing protocols and distribution methods are now enabling multicast implementations to move out of the LAN arena and into the larger world of the internet. Multicast's methods of operation pose new and extended demands on security models developed primarily for unicast data transmission. This paper examines the security implications of multicast communications as they relate to network management. It begins with a general description of multicast communications and then progresses to discussing multicast methods of operation within the Internet Protocol (IPv4) framework while contrasting them against the more familiar unicast operations. Security issues specific to multicast communications are identified and discussed. Possible solutions including the extension of IPsec to MIPsec are examined.