Highly integrated media access control

摘要

A supervisory communications device, such as a headend device within a communications network, monitors and controls communications with a plurality of remote communications devices throughout a widely distributed network. The supervisory device allocates bandwidth on the upstream channels by sending MAP messages over its downstream channel. A highly integrated media access controller integrated circuit (MAC IC) operates within the headend to provide lower level processing on signals exchanged with the remote devices. The enhanced functionality of the MAC IC relieves the processing burden on the headend CPU and increases packet throughput. The enhanced functionality includes header suppression and expansion. DES encryption and decryption, fragment reassembly, concatenation, and DMA operations.

主权项

1. A media access controller integrated circuit (MAC IC), comprising:
a pre-processor configured to receive an egress signal from a source node, and to extract payload frames included in the egress signal; a controller configured to identify a fragmented payload frame from among the extracted payload frames, and to reassemble the fragmented payload frame according to an instruction included in a header of the egress signal; and a post-processor configured to identify a suppressed packet header included in the extracted payload frames, and to expand the suppressed packet header according to a packet expansion rule.