Multi-Receiver Homomorphic Authentication Codes for Network Coding
The authors investigate a new class of Authenticate-codes (A-codes) that support verification by a group of message recipients in the network coding setting. That is, a sender generates an A-code over a message such that any intermediate node or recipient can check the authenticity of the message, typically to detect pollution attacks. They call such an A-code as Multi-Receiver Homomorphic A-code (MRHA-code). In this paper, they first formally define an MRHA-code. They then derive some lower bounds on the security parameters and key sizes associated with their MRHA-codes. Moreover, they give efficient constructions of MRHA-code schemes that can be used to mitigate pollution attacks on network codes. Unlike prior works on computationally secure homomorphic signatures and MACs for network coding, their MRHA-codes achieve unconditional security.