A communication between agents consists of an agent's utterance and the other agent's perception, thus, both of the utterance and the perception are regarded as parts of a communication channel between agents.
Information is regarded as a propositional content of a sentence.
An information channel where information flows can be considered to be a program, in the sense that it gets an utterance as an input and puts an output to be a perception of some agent. In the real situations, there are so called miscommunications. The Dynamic Behavior of Types and Instances - Stein, al. Doc 9 Intelligent Agents II - Wooldridge, Muller et al.