Understanding the Role of Routers in Networks

Routers provide physical connectivity between networks by virtue of their physical attachments to either local-area networks (LANs), such as Token Ring or Ethernet, or wide-area networks (WANs), such as Frame Relay or ISDN.

A router can be used to connect only LANs together, only WANs together, or any other combination. The term physical connection should not be taken too literally. Many networks make use of Microwave links for WAN connectivity. This means that no actual physical connection exists between two connected routers communicating over microwave circuits.

The Router Interface

A router's attachment to a LAN or a WAN is usually referred to as an interface but may also be referred to as a ...

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