Why is hdlc used

This field of the HDLC frame contains the user's data from the network layer or the management information. The length of this field varies from one network to another. There is a 16 bit CRC code for error detection. Learn Core Java.

Java Examples Java 8 Java 11 Java HTML 5 Interactive. CSS Interactive. C Language. Advanced Data Structure. Operating System. Computer Network. Computer Architecture. Android Development. Game Development. GO Language. Spring Framework. Go to Tutorials Library. Interactive Courses, where you Learn by doing. Available for FREE! Tutorials Library. A control field at the start of a frame is used for establishing and terminating data link connections. An HDLC link consists of a primary station and a secondary station, with the primary station issuing the commands and the secondary station issuing the responses.

Because HDLC is used mainly in point-to-point communication, it does not need to have addressing implemented at the data-link layer because the local and remote stations are connected directly. You can also use HDLC in a more complex configuration in which one primary links to several secondaries unbalanced multipoint configuration.

The standard code used is CRC cyclic redundancy code. There are three types of HDLC frames. They also include flow and error control information that is piggybacked on user data. The first bit of control field of I-frame is 0. They are used for flow and error control when piggybacking is not required. The first two bits of control field of S-frame is It may contain an information field, if required. The first two bits of control field of U-frame is