Medium access control device and method for optical packet-switched metro WDM slotted-ring networks

A medium access control (MAC) device for optical packet-switched metro wavelength division multiplexing (WDM) slotted-ring networks, applied in a node of an optical packet-switched metro WDM slotted-ring network, for providing data transmission services, the device comprising:

• a call admission control (CAC) module, configured in the node of the optical packet-switched metro WDM slotted-ring network in a distributed manner, wherein the CAC module flexibly allocates a reserved bandwidth to an isochronous traffic by a mean-rate-reservation method, controls a quota of the isochronous traffic below the reserved bandwidth, determines whether to accept a connection establishment request initiated by the isochronous traffic and determines the reserved bandwidth according to the following Formula (1), where Q is a quota of the node within a single cycle, and rH is a quota ratio having a value of 0 to 1:
• rH×Q Formula (1);
• and
• a MAC processor, for establishing a connection in the reserved bandwidth for the isochronous traffic accepted by the CAC module according to control information recorded in a control slot in a control channel, controlling data uploading, unloading, and erasing of a plurality of data channels, and updating corresponding contents in the control information.