In the Point-to-Point Protocol (PPP), the Link ControlProtocol (LCP) establishes, configures, and tests data-link Internet connections.Before establishing communications over a point-to-point link, each endof the PPP link must send out LCP�packets. The LCP packeteither accepts or rejects the identity of its linked peer, agrees uponpacket size limits, and looks for common misconfiguration errors. Basically,the LCP packet checks the telephone line connection to see whether theconnection is good enough to sustain data transmission at the intendedrate.� Once the LCP packet accepts the link, traffic can be transportedon the network; if the LCP packet determines the link is not functioningproperly, it terminates thelink.
LCP packets are divided into three classes:
- Link configuration packets used to establish and configurea link
- Link termination packets used to terminate a link
- Link maintenance packets used to manage and debug a link