Corebridge's protocol CATS - Common Access for Telephony Services - manages communications between Corebridge and most PBXs used in the marketplace. CATS makes communication with almost all phone manufacturers' protocols possible (TAPI, SIP, TSAP, Mitai, ...) So by enabling integration with existing PBXs, Corebridge gives enterprises the opportunity to bypass the potentially high costs and delays inherent in upgrading or replacing their telephone infrastructures because deploying Corebridge removes the necessity to implement a full IP solution. All information from PBXs is handled by the enterprise's IT systems. Instructions transferred between the server and PBXs by Corebridge are simple in nature, do not saturate the network and can help enterprises to realise centralised, optimised IT architectures.