Methods and systems are disclosed that support the aggregation of acknowledgement messages and control messages. Advantageously, acknowledgement and negative acknowledgement indications for multiple client nodes are combined into a single aggregated message which is broadcast or multicast to the multiple client nodes. Based on unique identifiers assigned to each client node, client nodes are grouped such that the aggregated acknowledgement messages can be efficiently encoded to conserve both network capacity when they are transmitted, as well as processing capacity when they are parsed by the client nodes. If code division multiple access (CDMA) technology is used, the aggregated acknowledgment message can be transmitted without CDMA spreading to effectively broadcast or multicast it to multiple client nodes. A similar technique can be employed for the efficient broadcast or multicast of aggregated control messages.