Packets transported over a serial data stream need to have their start and stop information encoded so that they can be parsed by the receiving device. Techniques used in various standards require extra bandwidth to carry this information. For framed data streams like T1, proprietary protocols have used the frame structure to mark packet boundaries. Both types of solutions are desirable for unframed, long distance data streams like the CCITT G.703 2.048 Mbps unframed service, subrate trunks, or fractional T1 services. The present invention provides a packet framing method that uses the Cyclic Redundancy Check (CRC) found in most packet formats. The protocol does not require any extra bandwidth and can work with any serial data stream physical layer.