All about wireless networking and NMS/EMS

Introduction: Administrative distance: Most routing protocols have metric structures and algorithms that are not compatible with other protocols. In a network with multiple routing protocols, the exchange of route information and the capability to select the best path across the multiple protocols are critical. Administrative distance is the feature that routers use in order to select the best path when there are two or more different routes to the same destination from two different routing protocols. Administrative distance defines the reliability of a routing protocol. Each routing protocol is prioritized in order of most to least reliable (believable) with the help of an administrative distance value. Select the Best Path Administrative distance is the first criterion that a router uses to determine which routing protocol to use if two protocols provide route information for the same destination. Administrative distance is a measure of the trustworthiness of the source of the

Event: An  event  is an occurrence or detection of some condition in or around the network. An event is a distinct incident that occurs at a specific point in time. Examples of events include: ·         Port status change ·         Device reset ·         Device becomes unreachable by the management station An event can also result from: ·         A fault that is an error, failure, or exceptional condition in the network. For example, when a device becomes unreachable, an unreachable event is triggered. ·         A fault clearing. For example, when a device state changes from unreachable to reachable, a reachable event is triggered. Alarm generated by NE and NMS: ·         By receiving notification events and analyzing them; for example, syslog and traps. ·         By automatically polling devices and discovering changes; for example, device unreachable. Alarm: An  alarm  is a NMS response to one or more related events. If an event is considered of high en