We consider a Rayleigh model [Foschini and Gans, Wirel. Pers. Commun. 6, 311 (1998)] for the Shannon capacity characterising wireless information transfer in a network of antennae. In this model, the capacity C is a linear statistic of the channel matrix of the network. We use this fact to calculate the variance [C] of the Shannon capacity. We find that the expected value 〈C〉 of the Shannon capacity is typical, that is the coefficient of variation is small. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)