Router metrics are metrics

Metric (mathematics)

In mathematics, a metric or distance function is a function which defines a distance between elements of a set. A set with a metric is called a metric space. A metric induces a topology on a set but not all topologies can be generated by a metric...

 used by a router to make routing decisions. It is typically one of many fields in a routing table

Routing table

In computer networking a routing table, or Routing Information Base , is a data table stored in a router or a networked computer that lists the routes to particular network destinations, and in some cases, metrics associated with those routes. The routing table contains information about the...

.

Router metrics can contain any number of values that help the router determine the best route among multiple routes to a destination. A router metric typically based on information like path length

Path length

In chemistry, the path length is defined as the distance that light travels through a sample in an analytical cell. Typically, a sample cell is made of quartz, glass, or a plastic rhombic cuvette with a volume typically ranging from 0.1 mL to 10 mL or larger used in a spectrophotometer. For the...

, bandwidth

Bandwidth (computing)

In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it .Note that in textbooks on wireless communications, modem data transmission,...

, load

Load (computing)

In UNIX computing, the system load is a measure of the amount of work that a computer system performs. The load average represents the average system load over a period of time...

, hop count

Hop count

In computer networking, hop count refers to the number of routers through which data must pass between source and destination. Each router along the data path constitutes a hop, as the data is moved from one Layer 3 network to another...

, path cost, delay

Network delay

Network delay is an important design and performance characteristic of a computer network or telecommunications network. The delay of a network specifies how long it takes for a bit of data to travel across the network from one node or endpoint to another. It is typically measured in multiples or...

, Maximum Transmission Unit

Maximum transmission unit

In computer networking, the maximum transmission unit of a communications protocol of a layer is the size of the largest protocol data unit that the layer can pass onwards. MTU parameters usually appear in association with a communications interface...

 (MTU), reliability

Reliability (computer networking)

In computer networking, a reliable protocol is one that provides reliability properties with respect to the delivery of data to the intended recipient, as opposed to an unreliable protocol, which does not provide notifications to the sender as to the delivery of transmitted data.A reliable...

and communications cost.