Wide Area Network (WAN) is a collection of various local area networks(LAN) to transmit the data to the large geographical area in the form of voice, video, image, files. A LAN is a small area network that connects the network only for a limited distance. Ethernet and wifi fall under the local area network. Merely, the network of all local area networks is called a Wide area network(WAN).

It connects different LANs and other networks for communication and to share and access data from one user to another user over a longer distance.

Wide Area Network(WAN) plays a significant role in the present world. Many Companies, Industrialists, Business holders, remote users are using WAN to be competing in the world.

Many user computers, organizations, employees use the WAN to communicate with another user computer, employees to access the information, discuss and share data all around the world. The third-party service providers are involved in the connection between the users and the internet. The Service provider is responsible for the transfer of data from one user to another user. Service providers supply a link to interconnect the distinct LANs to the internet.

Examples of Wide Area Network (WAN) 

Wide Area Network

Internet :

A very known example of WAN is the internet itself. The internet is a largely connected distributed network where any person can communicate with anyone, anywhere around the globe. There is no central control that interconnects different networks to carry data from one place to another in a small amount of time.

Bank dispenser :

A bank cash dispenser is a network that connects to the internet. It allows the customers to withdraw the amount of money and update the account details to the customer. Different WANs are connected to the internet using satellite links or leased lines.

How does Wide Area Network work?

As we have mentioned earlier, a Wide Area Network is a group of distant local area networks. In a local area network, the network is connected only for a certain distance. While In Wide Area Network, the network is connected across a longer distance.

Working of wide Area Network

There are numerous ways to connect through WANs. The ISP (Internet Service Providers) is responsible for the transfer of data from one user to another user. These service providers supply a link to interconnect the distinct LANs to the Internet.

A cellular connection is established with a communication satellite to communicate with distinct systems. The ISP(Internet service provider) connects to the telecommunication satellite to send the signals or information to distant locations. With the help of the telecommunication satellite, the ISP sends the information to the geographical area networks. We can access the internet with ISP(Internet Service Provider)

There are two types of WANs:

  • Switched WAN
  • Point to Point WAN

Switched WAN :

The above figure represents the Switched WAN. A switched node is used in global communication. It is a group of several point-to-point WANs that has more than two end connections. Several nodes have connected to the switches to transfer the data over to other nodes or a public network.

Point-to-point WAN :

Point-to-Point connection diagram represents the communication between two nodes. It provides a link between the two nodes of equal bandwidth. When a connection is established between modem and ISP, a leased line is dedicated on two sides to exchange the data among two devices.

For Example, if a person or a device wants to send information from one system to another, a leased line is created between the two systems by the HDLC method.

Technologies used in WAN

  • ISDN (Integrated service digital network).
  • SMDS (Switched Multi Megabit data service).
  • SONET(Synchronous Optical data Network).
  • HDLC(High Data link control).
  • SDLC(Synchronous data link control).

WAN Technologies 

  • Router: In simple words, a router is a device to transmit the data from one network to another network. It forwards the data in the form of packets. Each router consists of a network address that directly sends to the destination router.

Each router consists of a routing table that carries routes to the destination address.

Circuit Switching

  • Firstly, let us know the concept of Switching is a device that connects multiple communication lines. It maintains a one to one communication between two devices or systems.
  • The usual switch between the two communication lines gets activated to send information from one device to another device.

The Circuit switching employed in public telephone networks, all the public telephone networks are in the form of Circuit switching.

Data communication and voice communication uses circuit switching network. We obtain a path between the two networks by establishing a Switch between the two devices. This switch will find the route to the destination address.

Packet Switching

To Overcome the problems in circuit switching, we use packet switching. Packet switching divides the data into several packets and sends the packets sequentially to the destination address only one at a time.

The packet switching follows two approaches:

  • Data gram approach
  • virtual circuit approach

The data transmitted in packets. Each packet consists of the destination address and user information.

TCP/IP protocol 

TCP/IP (transmission control protocol/internet protocol) is a four-layer architecture. The main aim of TCP/IP to connect remote machines and to send data from one device to another device.


In frame relay, all the nodes connect to the frame relay network by using packet switching technology. The Frame relay comes under the WAN protocol with high-level performance. The data sent in different routes by dividing it into frames.

In Frame relay, it shares the bandwidth to different nodes so as there is no wastage of bandwidth and cost-free.

The main disadvantage of frame-relay is it doesn’t guarantee the reliable transmission of data packets.

  • Firstly, let us learn the concept of Switching, which is a device that connects multiple communication lines. It maintains a one to one communication between two devices or systems.

WAN Aggregation

WAN Aggregation is connecting different links at a single point connection to maintain the connectivity among all the other devices. As in evolving technology, Many companies, corporations are progressing their enterprises across the world. It’s hard to connect with the diversifying branches of their companies, to maintain connectivity, and to communicate among all their company branches. To Overcome this, WAN aggregation is the optimal solution. The aggregating is the connectivity from the corporate headquarters, multiple company branches to communicate with each other. The employees must able to access resources and applications without compromising security and privacy.

Currently, mobility and Social media have directed to increase in the usage of the applications leading to cause a drastic change in user behavior. With an increase in the utilization of applications, there is an enormous increase in data generations in diversifying locations and in many business functions. These consume higher bandwidth and demands security and privacy.

TCP Optimization

The TCP developed to look into how much data content is delivered. It defines the required bandwidth for transmission data. The TCP optimization is simply a Window Size that examines the time taken to wait for the transmission of data, to reduce the bandwidth and increase the performance of data transfer.


It minimizes the bandwidth by removing the data sent through a network before transmission.


When a router wants to send the information from one router to another router, it passes through a WAN Optimization box. The WAN optimization stores all the storage in actual data by dividing the data into multiple subparts. This Actual data sent to the other side of the network. The process of data transfer is called a cold Transfer. The second type of data transfer is to send the stored data again is called a Warm transfer.

Data duplication

It reduces all the duplicate data that increase space in the storage area and allows to store more non-redundancy data in it.

Difference Between LAN and WAN


1.It connects the group of the computer for a limited distance.

2.The Owner shop of a local area network is private.

3.Fast transfer of data without any data congestion.

4.The data get transmitted without any delay.

5.The speed of LAN is 1000 Mbps.

6.The data transfer rate is high in the local area network

7.There are fewer data errors in the local area network.

8.It has higher bandwidth in the transmission of data.

  1. schools, buildings are examples of LAN.


1.It connects the group of LANs for a longer distance.

2.The WANs network owned by an Internet service provider(ISP).or Private network.

3.The data transfer of data is slower.

4.The delay in data occurs during the transmission of data.

5.The speed of the WAN is 150 Mbps.

6.Low rate of data transfer in a Wide area network.

7.Data congestion and errors are present in WAN.

8.Lower bandwidth transmission of data.

9.Internet is the best Example for WAN.

WAN Security

Security is the most need in demand for today’s  WAN Technology.WAN Security is the constant threat in today’s public area network, and our dependency on WAN  increasing vigorously. The public network services are putting many users at risk regarding privacy and security.

WAN security is the Basic requirement to connect various companies to their corresponding databases.

If we want to access information from an external cloud service, a link between the client and server-side connected to the external IP address

It allows the Third-party to access the data from the database.

The SD-WAN is used as a default feature in many Corporate companies for security, optimization, and privacy in networks.

History Of WAN

Wide Area Network ( WAN ) that evolved in the early 1980s. It is a distributed network over a large geographical area. Many local area networks get connected to the WAN.

Wide Area Network can send the information from one branch office to the other branch offices or users at various locations. Many Corporations, business holders are maintaining the wide-area network to enhance and stand in this competitive world. It connects all the remote users, telecommunication services, various branch offices through a WAN.

In the 1970s and early 1980s X.25 networks are used in many corporate companies. As in expanding technology, modern WAN technology came into power. In the 1980s, the network is established only for the local area computers and personal computers with a speed of 56kbps.

In 1982, WAN Technology came into force, and soon more expensive and faster connections have been established.

In the early 1990s, ATM services and Frame Relay concepts were introduced that establish cloud services. These cloud services all the organizations and company critical information that no longer need to be maintained. Consequently, Mpls, VPNs, Frame relay concepts are coming into force. The Mpls uses an IP address within the same network. In different WAN technologies, there is a constant decrease in the bandwidth and make it available for all the organizations at a low cost.

Later, SD-Wans are increasingly in demand for all the public & private networks.

I have listed some Advantages and Disadvantages of Wide Area Network below.

Advantages of Wide Area Network

  • We can communicate through longer distance locations using WAN Technology.
  • We distribute the information to the branches of the companies, that are present at different locations.
  • A message can have images, audio, video, etc. These messages can be sent very quickly for far distances.
  • Any System user can access the data present in the network.
  • We can share the resources with a larger geographical area.
  • Multiple users can share and access the internet at a time.

Disadvantages of Wide Area Network

  • 1.Many Skilled technicians and network administrators are required to handle the network servers.
  • 2.There is no guarantee in the privacy of the users. It is easy to access the information for a third party.
  • 3.A good firewall is required to restrict third party users from accessing the data.
  • 4.Providing security to users is a little complex.
  • 5.It is a time-consuming process to resolve the issues regarding networks.
  • 6.The may be a delay in transmission of the data.
  • 7.Data congestion may, and errors may take place during the transmission of the data.

Traditional Circuit-Switched WAN

Switching is a device that connections multiple connection lines together.

To cause one-to-one communication between the two devices or systems, we apply the concept called Switching.

There are various technologies in the Switching concept :

The Switch is to get activated to transfer the information from two devices.

  • Circuit Switching
  • Packet Switching

Let us learn a little more about the circuit switching network:

Circuit Switching

In-Circuit Switching Network, a dedicated path is maintained to make a one-to-one connection between the two devices. While the transmission, all the packets work in the same Path, and fixed resources are allocated in circuit switching.

The below figure represents the Circuit Switching. All the Switches interlinked with each other through the channels. When Host A wants to communicate with Host B a circuit is set up between host A and Host B.

Host A will make a reservation of a channel before it transmits the data.

In Circuit-Switching, we have a guaranteed transmission of the signal with the fixed resources.


VOIP ( Voice over Internet protocol )

In the voice-over-internet protocol, all the phone calls from the user telephone will be sent to the service provider. This service provider receives the call as audio. VOIP is the connection between the user phone and the service provider to make the audio transmissions

VOIP packs different audio signals into the data packets with some protocols, these data packets are unpacked at the receiver end with the same protocols.

Due to abundant features and low-cost services, many organizations enterprises are using VOIP Technology.

Session initiation protocol, a session description protocol, skype protocol are some of the protocols we use in the VOIP.


In the early days, WAN connects different applications anytime from various locations. All the branches, headquarters of a company connected through a router using a leased line connection called Mpls. The leased line connections are perfectly acceptable at that time of the network. In leased line connections all the business functions are handled by the company datacenters.

Now, with an increase in cloud storage services, the traffic patterns of the data have been changed.

SD-WAN routes the traffic in WAN based priority, applications, and quality policies. SD-WAN guarantees a secure and reliable transformation of data over WAN Technology.

The SD-WAN is used as a default feature in many Corporate companies for security, optimization, and privacy in networks.

There are three Security possibilities :

  • Cloud-based security
  • Built-in Security
  • Third-party service

SD-WAN Architecture

Sd-WAN architecture is a datacenter that directs the data traffic across the WAN.SD-WAn is designed to support all the applications, data centers, and efficient security mechanisms. Most Organizations and enterprises prefer SD-WAN architecture since it provides low-cost and high-security mechanisms.

There are mainly two features of the SD-WAN architecture :

  • Centralized Orchestration
  • Zero Touch Provisioning

Centralized Orchestration

It reduces the cost expenses of the wide-area network by centralizing all the security policies and application performance.

Zero Touch Provisioning

It pushes all the configuration policies at a time to different branch locations manually. It results in consistent policies and reduces errors.

In SD-Wam enables the optimization and offload bandwidth from all the MPLs and private lines and improves the operational facilities.

WAN Virtualization

WAN virtualization works based on the RAID approach. It ensures the protection and reliability of networks. Virtualization is a combination of several network connections to provide higher bandwidth and more reliable connectivity.

Summary Of WAN

A Wide area network is a combination of multiple local area Networks.WE communicate through geographical locations in WAN Technology.

These network communications are established through leased communication. Most of the organizations, business holders, and companies are adopting this WAN Technology. As industries are evolving in diversifying directions the usage of the data, bandwidth capacity is increasing rapidly.

There are various types of connections to connect through the WAN:

The Internet Service Provider (ISP) is responsible for the connection between the WAN and the Organizations. Organizations should subscribe to the ISP service for Secure network connections. All the Data connections at different branches of an organization handled by the Interner Service Providers.

There are two types of WAN Connections Switched network and Point to point network. All the nodes and routers are connected through a switch is called a switched network. The End-to-End connection between the two nodes is called a point-to-point network. Circuit Switching, Packet Switching, Frame Relay are concepts used to reduce the data congestions and to send the data packets to the receiver side without any delay.

In the Wide Area Network, the data is divided into sub-packets and sent to the receiver side. All the techniques we use in WAN Technology is to improve the performance and bandwidth capacity of the Network. Internet is an example of a Wide area network where we can connect multiple devices, mobiles, systems and send data to multiple users at the same time.WAN aggregation, WAN Optimization, compression caching, data duplication concepts are used to increase the bandwidth capacity and performance of the WAN.

As in evolving Technology, there is a constant increase in data utilization and the need for bandwidth capacity. Many Organizations, companies use WAN Technology to communicate with their sub-branches, employees, and remote users of their company. Mobility and Social Media has brought a drastic change in user behavior. Instead of storing data in the company data centers, many organizations are using cloud service networking where there is no longer a need to check the data frequently, SD-WAN network controls and manages the different services and remote networks.

The main advantage of a Wide area network is, we can communicate across various branches, remote users, and employees situated at farther locations. Audio, video, images, files are transferred as data packets. In the Wide Area Network, there is no guarantee for user security and privacy. There will be a low bandwidth capacity and low data transfer rate due to the larger distance area. A Fire Wall enabling, anti-software installations should maintain for the User Security and Privacy.

Second Explanation of Wide Area Network

A Wide Area Network (WAN) is a communication network that spans a large geographical area. It can connect cities, states and parts of a country or even countries. The devices in a WAN are connected through public infrastructure such as a telephone system or through leased lines or even satellites. The Internet may be called as the largest WAN. Various, Local Area Networks (LANs) or Metropolitan Area Networks (MANs) are interconnected in a variety of ways and at different levels and accesses to form a WAN. Larger corporations or organisations which have their facilities located all over the world use WAN.

In a Wide Area Network (WAN) the user or organisation does not own the communication links or infrastructure that connects the remote computer system; instead, such a service is provided by a telecom/internet service provider. WANs transmit data at slower speeds than LANs. WANs are similar in their structure to a MAN, but its range of services cover distances greater than fifty kilometres.

WANs are used for data and image transmission and also for voice services. Due to the rapid progress of technology in the recent years and additions to the LAN connections over the years, there has been a significant surge in WAN usage. So, government entities, businesses, educational institutions, students, clients, buyers and suppliers are using WANs from various locations across the world at an unprecedented scale. WANs thus ensure that the connecting parties effectively carry out their daily functions regardless of their location thereby reducing distances and making the world a relatively smaller place.

How does the Wide Area Network (WAN) work?

A WAN may transmit data over long distances to connect various LANs, MANs or other computer networking architecture. But such LANs or MANs cannot transmit data over tens, hundreds or thousands of kilometres and herein WANs as they overcome this difficulty of covering distance ranges.

Since a WAN covers large distances as compared to LANs, Virtual Private Network (VPN) can help connect its various parts. VPN uses the public infrastructure over the internet and a variety of specialised protocol which support private communications. In simple terms, a VPN uses public telecommunication network to conduct private data communications by using authentication and data encryption. This helps in providing protected communication between sites over the internet.

Technologies used in implementing WAN

In the beginning, in the 1980s, technology standards such as X.25 were used. These kinds of networks supported credit card systems, automated teller machines (ATM) and some early online information systems. X.25 networks used 56 Kbps dial-up modem connection. A modem is a device which helps a computer transmit or receive its digital data over telephone or cable lines.

Later on in the 1990s, Frame Relay technology came into existence. This simplified the X.25 protocol thereby providing higher speeds in lesser the costs. Frame Relay is a network protocol technology designed to connect LAN and transfer data across WAN.

Multiprotocol Label Switching (MPLS) then replaced Frame Relay technology. This MLPS improved protocol support for handling voice and video traffic along with the normal data traffic. With increasing popularity in the 2000s, MLPS eventually replaced Frame Relay.

Nowadays, households are connected to the WAN using Dial-Up, ADSL (Asymmetric Digital Subscriber Line) which commonly uses a Gateway to make a connection, Cable, 4G or fibre opticATM (Asynchronous Transfer Mode), ISDN (Integrated Services Digital Network) are some other standards/technology for WAN implementation.

Speeds ranging from 28 kilo-bits/second to speeds as high as 100 Giga-bits/second (using an Ethernet 100GBaseY connection) have are being used by the people to connect to the internet. Trials were recently conducted in 2017 for business use of 400 gigabit Ethernet. An Ethernet simply helps in connecting computers together in a LAN using some protocol or a set of rules in order to facilitate data transmission.

Also, read…

I have listed some Advantages and Disadvantages of Wide Area Network below.

Advantages of a Wide Area Network (WAN)

WAN offers privacy and security. As a WAN provides a dedicated, direct and encrypted connection for data transmission, it increases the security of the system.

Update files and data are available on the servers of various software companies. So, all the users and administrators get updated version of data or files within a few seconds.

Sharing of software and resources can happen over long distances just like in a LAN.

High bandwidth is ensured due to the Network Performance Consistency as our data doesn’t compete with other internet data due to dedicated bandwidth. Leased lines could be allotted to achieve this.

Businesses have become global or their geographical reach has increased due to the access to the WANs anywhere.

 Disadvantages of a Wide Area Network (WAN)

  • We need secure connections over a WAN. Thus our computers/networks need firewalls and anti-virus software. Such requirements need to upgrade regularly as the threats become more pernicious.
  • Disconnection and server connection issues are also frequent, especially in remote areas.
  • The setup cost for WANs is high as it requires the purchase of routers, switches and extra security software. Such setups also have high maintenance costs.

Download Wide Area Network Advantages and Disadvantages in pdf – Click here