A communication channel has an associated channel authenticator that includes a channel identifier, a use policy identifying how an owner of the communication channel indicates the communication channel is used, and a digital signature over the channel identifier and use policy. The identifier of the communication channel and the use policy can be verified by a computing device, and a check made as to whether a current security policy of the computing device is satisfied by the use policy. An access that the computing device is allowed to have to the communication channel is determined based at least in part on both whether the current security policy is satisfied by the use policy and whether the identifier of the communication channel and the use policy are verified.