Specifications include, but are not limited to: Group 1: Traditional Telephone Line Services as replacement for existing Centrex, measured service business, unlimited service business telephone lines and trunks. Inclusive are intrastate, interstate and international calling, voice mail, and multiple line features. Group 2: Legacy Line/Data Services as replacements for low speed data transfer, dry line operation, alarm lines and voice radio circuits. Group 3: Advanced Telephone Services are those providing multiple channel or high speed connectivity to the Public Switched Telephone Network (PSTN) intended as replacements to the following: ISDN PRI with DID, dedicated T1 and SIP (Session Initiated Protocol) with DID technologies. Group 4: High Speed Data Transfer Services inclusive of replacements for point to point and switched circuit operations. Current services include dedicated point to point T1, Frame Relay, switched Ethernet interface services, and ATM service.