A network device stores back-off definitions for different service categories of machine-type communications (MTC). The network device receives a service connection request originating from a wireless terminal and identifies the service connection request as a MTC request. The network device identifies an available bandwidth capacity for at least one portion of a network associated with the MTC request and determines, when the available bandwidth is below an admission threshold capacity, an admission control level for the MTC request. The admission control level is selected from a group of different admission control levels. The network device calculates a retry interval for the MTC request based on the determined admission control level for the MTC request and the available bandwidth capacity, and sends the retry interval with a response for the MTC request.