customers, as clients were unlikely to be using a data service 45 percent of the time. In more recent years, Frame Relay has acquired a bad reputation in some markets because of excessive bandwidth overbooking. Telecommunications companies often sell Frame Relay to businesses looking for a cheaper alternative to dedicated lines; its use in different geographic areas depended greatly on governmental and telecommunication companies' policies. Some of the early companies to make Frame Relay products included StrataCom (later acquired by Cisco Systems) and Cascade Communications (later acquired by Ascend Communications and then by Lucent Technologies). As of June 2007, AT&T was the largest Frame Relay service provider in the US, with local networks in 22 states, plus national and international networks. FRF.12 When multiplexing packet data from different virtual circuits or flows, quality of service concerns often arise. This is because a frame from one virtual circuit may occupy the line for a long enough period of time to disrupt a service guarantee given to another virtual circuit. IP fragmentation is a method for addressing this. An incoming long packet is broken up into a sequence of shorter packets and enough information is added to reassemble that long frame at the far end. FRF.12 is a specification from the Frame Relay Forum which specifies how to perform fragmentation on frame relay traffic primarily for voice traffic. The FRF.12 specification describes the method of fragmenting Frame Relay frames into smaller frames. See also Multiprotocol Label Switching List of interface bit rates References External links – Multiprotocol Interconnect over Frame Relay – PPP in Frame Relay – Multiprotocol Interconnect over Frame Relay Broadband Forum - IP/MPLS Forum, MPLS Forum, ATM, and Frame Relay Forum Specifications Cisco Frame Relay Tutorial Frame Relay animation CCITT I.233 ISDN Frame Mode Bearer Services Network protocols Link protocols