Wide Area Network, commonly known as WAN is a computer network that extends over a relatively large geographical area. The locations they connect could be a few miles apart or halfway around the globe.
The largest WAN in existence is the Internet. A WAN functions like a Local Area Network (LAN), but on a larger scale.
Computers connected to a wide-area network establish connection mainly through public networks, such as the telephone system. They can also use leased telecommunication lines or satellites. Frame Relay, X.25, etc. are some of the common WAN protocols.
The entire objective of a WAN is always intended to allow various smaller networks from several locations to communicate with one another.
Let’s explore WANs more in-depth, understanding how they work, their benefits and limitations. We will also discuss the different WAN technologies.
What is a Wide Area Network? – Further explained
As the name implies, Wide Area Network (WAN) spans a large-scale geographical area such as across cities, states, or countries. They can be a private network, or they can be more public to join smaller networks.
The simplest way to interpret what a WAN is to see the internet as a whole, which is the world’s largest WAN.
The internet is a WAN as it connects several small-scale local area networks (LANs) or Metropolitan area networks (MANs).
Generally, TCP/IP is the protocol used for a WAN. The data transmission takes place with the utilization of hubs, switches, fiber optics, modem, and routers.
How does WAN network work?
You can relate the operation of WANs to a banking system, where hundreds of branches in different cities are connected with each other to share their official data.
On WAN, the users at different locations establish a connection to a central server. All the computers on the network have a link to a central database on the server.
These computers save data in real time, send queries to the server and fetch reports at the same time.
WANs can be point-to-point, incorporating a direct connection between two locations. It can also operate across packet-switched networks, in which data transmission happens in packets over shared circuits.
Point-to-point WAN service may include either analog dial-up lines, in which a modem is deployed to link the computer to the telephone line, or dedicated leased lines.
What are the advantages of WAN?
Business, education and government organizations apply wide area networks to relay data to employees, students, customers, and suppliers from diverse locations around the world.
In essence, this mode of telecommunication allows a business to carry out its daily function regardless of location effectively.
Let’s know about some of the critical advantages to establishing a WAN.
Covers large geographical area
Wan covers a large geographic area. If your office is in different cities or countries, then you can connect your office branches through WAN.
ISP (Internet service provider) can give you leased lines by which you can join different branch offices.
Centralised Data and IT Infrastructure
A WAN eradicates the need to purchase email or file servers for each office. Instead, you only need to set up a single server at your head office’s data center.
Having a WAN also offers easier server management. Also, setting up a WAN delivers significant economies of scale by providing a central pool of IT resources.
If you get leased lines, then it gives high bandwidth than standard broadband connection.
Corporate WANs often apply leased lines instead of broadband connections to form the backbone of their networks.
They also usually give unlimited monthly data transfer limits, so you can use these links as much as you like without increasing costs.
Improved communications not only surges efficiency but also boost productivity.
Setting up a WAN allows you to distribute sensitive data with all your sites without having to transmit the information over the Internet.
As WAN encrypts your data before transmission, it adds a layer of protection for all the confidential material.
With so many hackers out there just waiting to steal sensitive corporate data, your business demands all the safety it can get from network intrusions.
Another benefit of WAN is that you can distribute your work to other locations. For example, you have an office in abroad, then you can hire people from any other country and communicate with them efficiently over WAN.
It also reduces your travel expenses as you can monitor the activities of your team online.
What are the limitations of a WAN network?
WANs have their share of problems too. The three most critical limitations are high setup costs, security concerns, and maintenance issues.
Security is a critical matter when it comes to WAN. As it employs various technologies combined with each other, a security gap can appear.
WANs open the way for certain types of internal security breaches, such as unauthorized use, information theft, and malicious damage to files.
It requires the use of firewall and security software/protocols at multiple points across the entire system.
Troubleshooting and Maintenance problems
There is no doubt that maintaining a WAN is a challenge. Some maintenance concerns include link quality and performance degradation, on-demand throughput, bandwidth management, scalability.
As WAN covers a larger area so fixing the problem associated to it are also difficult.
Connectivity and Speed issues
Due to its typically massive size, WAN’s are almost always slower than a LAN. The more the distance, the slower the network. That’s why you can often face connectivity issues or slow Internet speed issues.
The solution to this is to purchase a dedicated line from your Internet service providers.
High setup cost
WANs are complicated and complex networks, so they are rather expensive to set up for the first time. The primary reason for high setup costs is the need to connect far-flung remote areas.
It may involve purchasing routers, switches, and extra security software.
Having your own private WAN can be expensive. However, if you want a public network, you can set up WAN using just software (SD-WAN), which decreases setup costs.
Which networking technologies are used to implement WANs?
WAN technologies typically operate at the physical, data link and the network layers of the Open Systems Interconnection (OSI) reference model. Let’s take a closer look.
X.25 is one of the earliest protocols used to deliver WAN traffic. It uses packet-switching exchange nodes (PSEs) for the hardware that drops traffic onto the wires connecting sites in standard-sized packets. It includes error correction.
The physical links include leased lines, dial-up telephone services or Integrated Services Digital Network (ISDN) connections. It’s not used much anymore.
Frame-relay provides point-to-point and point-to-multipoint circuits with a shared network, which is inexpensive than a dedicated line.
It places data into different-sized frames and leaves error correction and retransmission of missing packets up to the endpoints.
Also, Frame Relay relies less on dedicated connections to create meshed networks, meaning fewer physical circuits, hence saving your money. Frame Relay technology was designed to simplify X.25 protocols.
DSL (Digital Subscriber Line) became a popular choice for high-speed Internet access because it uses the analog phone cables that are readily available in all homes or buildings.
The speed that you get depends on the distance between your home and the phone company. Most DSL providers offer asymmetric speeds; the downstream bandwidth is higher than the upstream bandwidth.
Cable Internet is similar to DSL. It also became popular since most homes and buildings have a cable connection.
It uses the DOCSIS (Data over Cable Service Interface Specification) standard to transport data over a coaxial cable.
Coaxial cables offer more frequency range than the two pair phone cables we use for DSL, allowing higher throughput. Cable internet often provides higher bandwidth, but this can depend on the number of subscribers on the network.
Asynchronous Transfer Mode (ATM) is just like frame relay.
However, in ATM data is broken into standard-sized packets called cells. These cells make it possible to combine different classes of traffic onto a single physical circuit and more easily guarantee the quality of service.
The drawback of ATM is that as it uses relatively small cells, the headers consume a large percentage of the information of each cell. Consequently, ATM’s overall utilization of bandwidth is less efficient in comparison to frame relay.
MPLS, an acronym for Multi-Protocol Label Switching is used to carry many corporate data across WAN links.
It was built to replace Frame Relay by improving protocol support for handling voice and video traffic in addition to regular data traffic.
The main highlight of MPLS is the Quality of Service (QoS) features.
In MPLS, short header segments, namely, labels allow MPLS routers to quickly determine the location to forward packets and to treat them with the class of service indicated by the labels.
Thus, different protocols within MPLS packets can run while giving different applications appropriate priority as traffic travels between sites.
Final thoughts on Wide Area Networks
To summarize, WANs are large telecommunication networks that connect locations over a wide geographical area, including cities, states, countries, and continents. WANs are structured and can operate quite efficiently.
The perks of using a WAN are countless. Without wide-area networks, it would not be possible to create unified networks for organizations with far-flung locations, to telecommunicate. However, the sophistication naturally increases the cost factor.
WANs are continually evolving to carry more and more traffic. Now, it is just up to you to use them in the right way to benefit from them and to make an informed decision on the viability of a WAN for your company.