1. A method of communication in a communication network including first and second network entities, said method comprising: receiving at the second network entity at least one message communicated over-the-air by the first network entity, said at least one message including one or more message fields indicating a number of concurrent over-the-air service instances with the second network entity supported by the first network entity; and said second network entity limiting a number of concurrent over-the-air service instances requested by the second network entity in accordance with said one or more message fields in said at least one message.