What Is a Wide Area Network (WAN)?
Without wide-area networks (WAN), it would be impossible to telecommute, create unified networks for organisations with multiple locations, or do anything else online. However, WANs do exist and are constantly evolving to carry more and more traffic faster as demand grows and technology improves.
What is a Wide Area Network-WAN?
A wide area network-WAN is a computer network that connects smaller campus and metropolitan area networks in various locations into a single, distributed network covering a large geographical area by using various links-private lines, Multiprotocol Label Switching (MPLS), virtual private networks (VPNs), wireless (cellular), and the Internet. The locations could be just a few miles apart or halfway around the world. A wide area network is used in the enterprise to connect regional and branch offices, as well as individual remote workers, to centralised resources.
History of Wide Area Network
The United States Air Force established the first known WAN in the late 1950s to connect sites in the Semi-Automatic Ground Environment (SAGE) radar defense system. An extensive network of dedicated phone lines, telephones, and modems connected the sites.
The Advanced Research Projects Agency Network (ARPANET), the first wide-area packet-switching network with distributed control and the first network to implement the TCP/IP protocol suite, laid the groundwork for the IP-based Internet.
ARPANET originally linked the universities of California, Los Angeles (UCLA), Stanford Research Institute (now SRI International), University of California, Santa Barbara (UCSB), and Utah.
While LANs are typically maintained by an organization’s own IT staff, WANs are frequently reliant on physical connections provided by telecommunications carriers, at least in part. The type of connections or communication protocols to use, as well as how to deploy them, will guide the development of your WAN architecture.
Protocols used in Wide Area Network
Multi-protocol label switching is now widely used to transport corporate data across WANs. Within an MPLS network, brief header segments known as labels allow MPLS routers to quickly decide where to forward packets and how to treat them based on the class of service indicated by the labels. This allows different protocols to run within MPLS packets while also giving different applications appropriate priority as traffic travels between sites.
One protocol commonly carried within MPLS is Internet protocol (IP), which became more prevalent in the 1990s.
X.25, frame relay, and ATM were previously popular protocols.
For the hardware that drops traffic onto the wires connecting sites, X.25 employs packet-switching exchanges (PSE). It includes error correction and standard-sized packets delivered in order.
Frame relay divides data into different-sized frames and leaves error correction and packet retransmission to the endpoints. These distinctions accelerate the overall data rate. It can save money by using fewer circuits because it is a switched service.
Asynchronous Transfer Mode (ATM) is similar to frame relay with one major difference: it uses standard-sized packets called cells, allowing multiple classes of traffic to be blended onto a single physical circuit while ensuring quality of service. The disadvantage is that ATM is inefficient because cells are relatively small, and their headers consume approximately 10% of the cell.
WAN connection types
WANs were initially built with meshed webs of private lines purchased from telecommunications carriers, but packet-switched services such as MPLS, frame relay, and ATM now predominate. A service provider can connect a site to many other sites using a single WAN connection to the carrier’s network. The internet can also be woven into the mix for certain types of traffic to provide less expensive WAN connections.
What exactly is tunnelling? What exactly is a VPN?
WAN connections that operate over the internet or some other public network generally use a technique known as tunneling. In a tunneled connection, the private-network data and protocol information are encrypted and encapsulated in IP packets that are routed over the open internet. When those packets arrive at the destination, the IP headers are stripped away, the payload is decrypted and private-networking features come back into play.
The most common tunnel is the virtual private network ( VPN ). VPN connections encrypt data in order to keep it private as it travels over public networks. VPN s are frequently used to allow home office workers to connect to private corporate WANs.
Today’s WANs may use multiple types of connections and protocols at the same time, adding to the complexity. As a result, the use of software-defined technology to manage wide area networks (WANs) is gaining traction. Software-defined WAN (SD-WAN) extends software-defined networking concepts to the WAN.
SD-WAN software monitors the performance of all WAN connections—MPLS, dedicated circuits, and the internet—and selects the best connection for each type of traffic. Teleconferencing may use a dedicated circuit, whereas email may use the internet. SD-WAN software makes decisions based on how well each link is currently performing, the cost of each connection, and the needs of each application.
SD-WAN was originally intended to create hybrid WANs and use policies to mix MPLS and internet connections in order to improve efficiency and lower costs. SD-WAN connections were invaluable as office workers fled to their homes during the coronavirus pandemic, and the market is expected to grow by 168% by 2024, according to the Dell’Oro Group.
SD-Branch, a subset of SD-WAN, is assisting in reducing the need for hardware within branch offices. Many physical devices can be replaced by software running on off-the-shelf servers, according to offerings from major vendors such as Aruba and Juniper. As the cost of wireless WAN technology (4G, LTE, 5G, etc.) decreases, mobile backup across an SD-WAN can provide a failover for broadband connections.
A WAN connection is a potential vulnerability through which an attacker could gain access to a private network. A virtual private network (VPN) that sits on top of the underlying physical network can provide authentication, encryption, confidentiality, and non-repudiation.
In addition to networking features, many SD-WAN offerings include security services, which should be considered during deployment.
WAN administration and optimization
Because data transmission is still governed by physical laws, the greater the distance between devices A and B, the longer it takes for data to travel between them. Network congestion and dropped packets can both degrade performance.
Some of this can be addressed through WAN optimization, which increases the efficiency of data transmissions. Because WAN links can be costly, technologies that reduce the amount of traffic crossing WAN links and ensure it arrives efficiently have emerged. These WAN optimization methods include data reduction (deduplication), compression, and caching (putting frequently used data closer to the end user).
Traffic can be shaped to prioritise time-sensitive applications like VoIP over less urgent traffic like email, which helps improve overall WAN performance. This can be formalised in quality-of-service settings that define traffic classes based on the priority each class receives in comparison to others, the type of WAN connection that each traffic type will use, and the bandwidth that each receives.
WAN optimization, which was previously a separate category, is now absorbed by SD-WAN.
Types of WAN technologies
Packet switching is a data transmission method in which a message is divided into several packets that are sent independently, in triplicate, over the best route for each packet, and then reassembled at the destination. Each packet includes a payload and an identifying header that includes destination and reassembly information. To check for packet corruption, the packets are sent in triplicate. Every packet is verified by comparing and confirming that at least two copies match. When verification fails, a request is made to resend the packet.
Packet over SONET/SDH (PoS)
Packet over SONET is a communication protocol that is primarily used for wide-area network (WAN) transport. It specifies how optical fiber point-to-point links communicate when using SONET (Synchronous Optical Network) or SDH (Synchronous Digital Hierarchy) communication protocols.
TCP/IP Protocol Suite
TCP/IP is a protocol suite of basic communication protocols that are used to connect network devices on today’s Internet and other computer/device networks. TCP/IP is an acronym that stands for Transmission Control Protocol/Internet Protocol.
An Overlay Network
A data communications technique in which software is used to create virtual networks on top of another network, typically a hardware and cabling infrastructure, is known as an overlay network. This is frequently done to support applications or security capabilities that are not provided by the underlying network.
A router is a networking device that connects LANs to form a wide area network (WAN) and is therefore referred to as a WAN device. IP addresses are used by IP routers to determine where to forward packets. An IP address is a numeric label assigned to each network device that is connected.
Frame Relay is a technology for sending data between LANs or WAN endpoints. It defines the physical and data-link layers of digital telecommunications channels through the use of packet switching.
Frame Relay encapsulates data in frames and transmits it over a shared Frame Relay network. Each frame contains all of the information required to route it to its destination. The original purpose of Frame Relay was to transport data across telecom carriers’ ISDN infrastructure, but it is now used in a variety of other networking contexts.
Multiprotocol Label Switching (MPLS)
MPLS is a technique for optimizing network routing. To avoid time-consuming table lookups, it directs data from one node to the next using short path labels rather than long network addresses.
ATM (Asynchronous Transfer Mode) is a switching technique that was widely used in early data networks but has since been largely replaced by IP-based technologies. ATM encodes data into small, fixed-sized cells using asynchronous time-division multiplexing. In contrast, today’s IP-based Ethernet technology employs variable packet sizes for data transmission.
Wide Area Network FAQs
What is the difference between WANs and LANs?
A wide area network-WAN is frequently contrasted with a local area network (LAN). LANs are networks that are typically restricted to a single building or a small campus. A LAN is your home Wi-Fi network.
The technologies and protocols that make LANs simple to set up do not scale beyond a certain limit or to truly massive numbers of endpoints. A WAN’s purpose is to connect one or more LANs and deal with those scales. The networking technologies and protocols used to transmit information in a wide area network differ from those used in a local area network.
When we talk about WANs, we usually refer to private or semi-private networks that connect distant LANs. For example, branch offices in different cities may share private internal corporate resources via a WAN.
What Is the Purpose of a WAN Connection?
There wouldn’t be any way to spread out an organization’s reach if Wide area network-WAN connections didn’t exist. For most organizations, LANs would allow them to work in their own building, but expanding to other cities or countries would be prohibitively expensive because of the infrastructure required.
WANs allow organizations to communicate between branches, share information, and stay connected as they grow and become more international. A wide area network (WAN) provides employees with the information they need while on the road for work. Sharing information with customers and partners, such as B2B clients, is also facilitated by WANs.
WANs, on the other hand, provide a vital service to the general public. A student at a university might use a wide area network to access university databases or conduct research. People use WANs to communicate, bank, shop, and more on a daily basis.
What exactly is WAN optimization?
In enterprise WANs, latency and bandwidth constraints frequently cause performance issues. Deduplication, compression, protocol optimization, traffic shaping, and local caching are all used in WAN optimization. These techniques improve packet delivery and traffic control, allowing network bandwidth to be dynamically increased or decreased as needed.
SD-WAN technology and WAN optimization can be used independently or in tandem. Some SD-WAN vendors are incorporating WAN optimization capabilities into their products.
What are the advantages of a Wide Area Network?
WAN eliminates the need for multiple servers in the office. A wide area network centralises and simplifies your company’s server management by allowing all of our different sites to share data from the server at head office. Data from multiple branches synchronizes with head office, while also providing the entire company with a central IT resource to manage.
When compared to solely relying on local area networks, installing a WAN allows you to:
- Integrate on a Massive Scale – WANs enable fast, dependable communication across continents or even the entire globe. If your company has multiple offices separated by hundreds or thousands of miles, this allows you to conduct business more efficiently.
- Enhance Remote Access – With a WAN, you don’t have to be in your physical office to access critical data and software. This allows employees to work from home or while traveling.
- Low-Cost Contact – Once the necessary infrastructure is in place, connecting to a WAN is less expensive than integrating with multiple LANs for clients, suppliers, and other third parties.
- It will protect your privacy – Sending data across a wide area network is more secure than sending it over the internet, so any files you share across your company will be more secure. WAN improves information security by keeping sensitive information out of the wrong hands. With BT’s SD-WAN, your information is also encrypted for added security.
- It has more bandwidth – Because WANs are powered by peer-to-peer leased lines or ethernet VPNs, your network can operate at a higher bandwidth than broadband, allowing you to transfer data faster from site to site.
Wide area network-WAN technologies aren’t just for Earth. NASA and other space agencies are developing a dependable “interplanetary internet” to send test messages between the International Space Station and ground stations. The Disruption Tolerant Networking (DTN) programmed is the first step toward providing an internet-like structure for communications between space-based devices, such as the Earth and Moon or other planets. However, barring any dramatic advances in physics, network speeds would most likely be limited to the speed of light.