High Quality Content by WIKIPEDIA articles! UniDirectional Link Detection (UDLD) is a data link layer protocol from Cisco Systems to monitor the physical configuration of the cables and detect unidirectional links. UDLD complements the Spanning Tree Protocol (STP) which is used to eliminate layer 2 loops. If two devices, A and B, are connected via a pair of fibres, one used for sending from A to B, other from sending from B to A, it is a bidirectional link (two-way link). If one of these fibres are broken, we're left with a unidirectional link (one-way link). The goal of the UDLD protocol is to detect whenever a bidirectional link is either broken, such that packets are sent only from one device to another, or connected wrongly, such that the fibres are connected to different ports.

Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.