High-level data link protocol(HDLC) and Synchronous data link protocol(SDLC) are both types of data link protocol layers that provide reliable service over physical communication links. The main difference between HDLC and SDLC is that HDLC is an asynchronous protocol while SDLC is a synchronous protocol.
What is HDLC?
High-level data link protocol (HDLC) is an asynchronous data connection layer protocol with transparent bit-oriented coding. It was produced by the International Organization for Standardization. It also supports connection-oriented as well as connectionless services.
What is SDLC?
Project management typically uses a structure called the SDLC, or software development life cycle. It outlines the steps and activities involved in implementing the directives as well as every stage of developing and data processing computers to carry out particular jobs.
Difference between HDLC and SDLC
- HDLC has an option for the checksum of 32-bit but does not support the configurations of the loop or hub go-ahead. SDLC does support the configurations of the loop or hub go-ahead.
- HDLC is considered a superset of SDLC because SDLC was submitted to various standards committees by IBM committees, namely ISO-modified SDLC led to the creation of HDLC protocol.
- HDLC is actually adopted from SDLC.
- In contrast to SDLC, HDLC features the asynchronous balanced mode functionality.
- HDLC supports frames that are not multiple of bit octets while SDLC does not.
- In contrast to SDLC, HDLC is a standard protocol.
- HDLC removed some procedures that were present in SDLC.