Someone

ISDN Serial3/1:23 interface
        dsl 1, interface ISDN Switchtype = primary-ni
    Layer 1 Status:
        ACTIVE
    Layer 2 Status:
        TEI = 0, Ces = 1, SAPI = 0, State = MULTIPLE_FRAME_ESTABLISHED
    Layer 3 Status:
        1 Active Layer 3 Call(s)
        CCB:callid=50, sapi=0, ces=0, B-chan=1, calltype=VOICE
    Active dsl 1 CCBs = 1
    The Free Channel Mask:  0x807FFFFE
    Number of L2 Discards = 0, L2 Session ID = 3
    Total Allocated ISDN CCBs = 1