Description: The High Level Data Link Control protocol was developed by the International Organization for Standardization (ISO). It is used for switched and non-switched networks and is a bit oriented architecture. The High Level Data Link Control has been accepted and used widely because it supports almost all kinds of functionalities like half duplex, full duplex, point to point and multi-point networks. The bit patterns are standard in HDLC and therefore the information exchanged follows the same pattern. This minimizes the chances of any errors.