The layer 2 protocol used by POS technology offers a standarized way for mapping IP packets into SONET/SDH payloads. Select the correct sequence of POS operation.
1) Data is scrambled and synchronous mapping takes place by octet into the SONET/SDH frame.
2) Encapsulated via Point-to-Point Protocol (PPP) takes place framing information is added with High-level Data Link Control (HDLC).
3) Gaps between frames are filled with flags, set to value 7E.
4) Octet stuffing occurs if any flags or resultant escape characters (of value 7D) are found in the data.
5) Data is segmented into an IP datagram with its 20-byte IP header.
A.
1,2,3,4,5
B.
1,3,4,5,2
C.
2,3,5,4,1
D.
5,2,3,4,1
E.
5,2,3,1,4