the cc operates in a similar manner but is responsible only for calls within a specified area the cc is allocated calls by the fc and passes these connections to a mrm under its control on the basis of traffic load on the mrms and their reported quality and capacity estimates the cc maintains a knowledge base ie a resource data base of its mrms and their loading it also receives reports from each mrm of its expected loading based on the connections it currently has and the channel quality it is currently experiencing the cc monitors the quality of the connections within its control and switches connections between mrms as required to maintain their quality the cc can also switch radio resources between mrms within its area to maintain quality targets if a mrm alerts the cc that quality cannot be met for one of its connections then the cc has several alternatives it can hand over the connection to another mrm as information about other mrm performance is maintained in the cc knowledge base it can release some resources from other connections by changing their service modes or in the extreme situation drop low priority connections it can change the service mode of the connection to a service mode which requires fewer resources this option is available only in the case of multi mode contracts if the cc cannot cope with the degradation then it alerts the fc qos degradation the cc forwards aggregate service quality measures to the fc a mrm controls resources on a single link of the system monitors the quality on the connection or connections allocated to it and uses link control.