ITU-T Rec. G.706 - FRAME ALIGNMENT AND CYCLIC REDUNDANCY CHECK (CRC) PROCEDURES RELATING TO BASIC FRAME STRUCTURES DEFINED IN
1 General
2 Frame alignment and CRC procedures at l544 kbit/s interface
    2.1 Loss and recovery of frame alignment
        2.1.1 Loss of frame alignment
        2.1.2 Recovery of frame alignment
    2.2 CRC bit monitoring
        2.2.1 Monitoring procedure
        2.2.2 Monitoring for false frame alignment (see § A.1.1)
        2.2.3 Error performance monitoring using CRC-6 (see § A.1.2)
3 Frame alignment and CRC procedures at 6312 kbit/s interface
    3.1 Loss and recovery of frame alignment
        3.1.1 Loss of frame alignment
        3.1.2 Recovery of frame alignment
    3.2 CRC bit monitoring
        3.2.1 Monitoring procedure
        3.2.2 Monitoring for false frame alignment (see § A.1.1)
        3.2.3 Error performance monitoring using CRC-5 (see § A.1.2)
4 Frame alignment and CRC procedures at 2048 kbit/s interface
    4.1 Loss and recovery of frame alignment
        4.1.1 Loss of frame alignment
        4.1.2 Strategy for frame alignment recovery
    4.2 CRC multiframe alignment using information in bit 1 of the basic frame
    4.3 CRC bit monitoring
        4.3.1 Monitoring procedure
        4.3.2 Monitoring for false frame alignment (see § A.1.1)
        4.3.3 Error performance monitoring using CRC-4 (see § A.1.2)
5 Frame alignment and CRC procedures at 8448 kbit/s interface
ANNEX A … Background information on the use of cyclic redundancy check (CRC) procedures
    A.1 Reasons for application of CRC
        A.1.1 Protection against false frame alignment
        A.1.2 Bit error monitoring
    A.2 Limitations of CRC procedures
        A.2.1 Probability of undetected bit errors
        A.2.2 Limitation of application to bit error ratio measurement
Reference