Start & end flags w/ bit stuffing
- Frame begins and ends with 01111110 called flag byte.
- When senders DLL senses 5 consecutive 1’s it “stuffs” a 0 into the bit stream.
- Receiver sees the 5 consecutive 1’s followed by a 0 and destuffs it (i.e., deletes the 0).
- Bit stuffing unambiguously locates frame boundaries.