In telecommunications, the term routing refers to the pathfinding of information or data streams, from the source to its destination. It is mostly used in the context of data networks and describes the route taken via individual network nodes (routers) for the transmission and delivery of data packets. In order to achieve this, the router knows either individual links or complete network topologies and chooses the best network node to forward the data packet on to next, based on its destination address and certain criteria. Routing algorithms and protocols are used to reach the decision. The term routing is also used for the inbound and outbound processing of telephone calls in telephone systems.

Routing in telephone systems

Routing in telephone systems
The main distinction is made between outgoing (outbound) and incoming (inbound) routing in telephone systems. Powerful telephone systems often have a variety of criteria which it can use when forwarding telephone calls. For call centres in particular, routing is a key feature of the phone system and essential for the efficient processing of customer calls.

Inbound routing in telephone systems

Depending on defined information, incoming calls are assigned to specific individuals, phone lines or groups. Voice response systems are often used to gather information about the caller. They give the caller the option to specify their request in more detail. Using definable criteria the telephone system transfers the caller to a staff member who is suitably skilled to act on the caller's concern. This feature-based routing optimises call agent availability, as well as improving the efficiency of how the calls are handled.

Outbound routing in telephone systems

One example of how outbound routing can be used in telephone systems is when finding the most favourably priced telephone provider for specific calls. The technical term for this is Least Cost Routing. The method generally uses the Call-by-Call feature, automatically comparing pricing tables. By using a call prefix number that is automatically pre-selected by the system, every call can be routed via the call provider that is offering the cheapest rate for that specific call. Call-by-call, however, must be supported and enabled by the user's own telephone provider. The Least Cost Routing function can be implemented through software in a telephone system or additional hardware.

Further information


A router is a switching device for networks, which is able to route network packets, based on their addresses, to other networks or devices. Among other things, they are used for Internet access, for...

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