A router is a device that connects two or more networks or subnets with packet switching. Performs two main functions: traffic management between these networks by forwarding data packets to the intended IP addresses and allowing multiple devices to use the same Internet connection.
There are several types, but most transfer data between LAN (local area networks) and WAN (wide area networks).
A LAN is a group of connected devices limited to a specific geographical area. A LAN usually requires one router.
WAN, on the contrary, is an extensive network spread over a vast geographical area. For example, large organizations and companies operating in several locations across the country will need separate local area networks, which are then connected to other LANs to form a global network. Since the WAN is distributed over a large area, it often requires multiple routers and switches.
Principles of operation
Routers access internal routing tables to decide how to route packets over network paths. The routing table records the paths packets must take to reach each destination the router is responsible for. You can compare this to the train schedule that train passengers refer to decide which train to take. Routing tables perform the same function; only they are created for laying data transmission routes, not for trains.
Routers work as follows: when it receives a packet, they read the packet headers — these are small data packets attached to packets that provide helpful information, including information about where the packet is coming from and where it is going. For example, the delivery information is printed on the outside of a postal parcel to see its intended destination, similar to how a train conductor can check a passenger's tickets to determine which train they should travel on. It then determines where to route the packet based on the information in its routing tables.
Routers do this million of times per second with millions of packets. As a packet travels to its destination, it may be routed multiple times by different routers.
Routing tables can be static or dynamic. The static routing tables do not change. The network administrator manually configures static routing tables. This fixes the routes of data packets over the network unless the administrator manually updates the tables. Such tables are more suitable for small networks.
Dynamic routing tables are updated automatically. Dynamic routers use various routing protocols to determine the shortest and fastest paths. They also make this determination based on how long packages take to their destination — similar to how Google Maps, Waze, and other GPS services determine the best driving routes based on past driving characteristics and current driving conditions.
Dynamic routing requires more computing power, so it is more suitable for medium and large networks because it is much more efficient.
According to their purpose in corporate networks, routers are divided into several types:
Core Router: unlike routers used in home networks or small business LAN, the core is used by large corporations and enterprises that transmit a large volume of data packets on their network. They work in the "core" of the network and do not interact with external networks.
Edge router: while the main router manages data traffic exclusively in a large-scale network, the edge router interacts with both core routers and external networks. The border guards are on the "edge" of the network and use BGP (Border Gateway Protocol) to send and receive data from other LANs and WLANs.
Virtual: This software application performs the same functions as a standard hardware router. This concept is closely related to VRRP (Virtual Router Redundancy Protocol), a network protocol designed to increase the availability of routers that act as the default gateway. This is achieved by combining a group of routers into one virtual router and assigning them a shared IP address, which will be used as the default gateway for computers on the network.
Why InfoTel:
- Since 2004, he has been engaged in implementing telecommunications and information solutions.
- We practice a systematic approach – we analyze the existing infrastructure and design, implement and maintain systems.
- License for installation of engineering networks.
- Partner of well-known global manufacturers of active network equipment, such as Alcatel-Lucent Enterprise and Huawei, whose product line contains all the necessary elements for building and centralized management (Network Management System) of a corporate LAN.
Our company's specialists cannot only design and select the optimal switch models for each specific task and structural element of a corporate LAN but also install and start up the developed turnkey technical solution.
In the product catalog, you can get acquainted with most types of equipment we use. The catalog shows retail prices. You should contact our sales department to get complete information and project discounts.
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