What Is a Wide Area Network (WAN)? Definition, Types, Architecture, and Best Practices

Let’s say a company’s headquarters are in Amsterdam. The company has branches in Berlin, Cairo, and Detroit, along with retail outlets in Edinburgh and Florence. The company needs a secure networking infrastructure to connect these locations outside the public internet. This is where a wide area network (WAN) comes into play to connect these distributed environments and enable secure data exchange within all of the company’s networked devices across all six cities.

What Is a Wide Area Network (WAN)?

A wide area network (WAN) is a group of networked systems distributed across a large geographic area. The networks remain connected to exchange data within the defined WAN group. The distance can be as small as a few feet and range to as far away as cities, territories, or nations. Technically, any network group that isn’t within local proximity of each other forms a WAN. For example, the public internet we use daily is a type of WAN, as devices located around the world communicate with each other.

However, the phrase “wide area network” has a more specific meaning in enterprise IT. It refers to a group of connected networks operating in a private environment, typically run by a single company, a conglomerate, a government, or a group of government agencies. Let us look at a few examples of WAN solutions available in the industry to understand this concept further.

Types of Wide Area Network (WAN)

WAN can be classified into two broad categories based on how they connect the endpoints: via a central device (switched) or through a dedicated line (point-to-point).

1. Switched WAN

In a switched WAN network, multiple component LANs are connected via a shared networking infrastructure. A WAN switching exchange at the center governs how network resources are distributed across locations in conjunction with the network appliances at each location. Switched WAN is best suited to distributed environments where network configuration requirements are largely homogenous.

• Number of component local networks: More than two, going up to hundreds or thousands of locations
• Technology used: Asynchronous transfer mode or an ATM network
• Application: Large, distributed environments

2. Point-to-point WAN

In a point-to-point WAN environment, two LANs or end nodes are connected through a dedicated and secure leased line. Old school broadband networks using dial-up technology are a good example of point-to-point WAN. Modern enterprises also use this type of WAN to enable secure and customized network performance between two locations. Each of the two end nodes is further connected to multiple devices to create a local area network.

• Number of component local networks: Two, but each local area network (LAN) can be large
• Technology used: Point-to-point tunneling protocol or PPTP
• Application: Two high priority locations

WANs can also be classified based on the underlying technology:

WAN Technology Types

• Dedicated internet access (DIA) WAN: A high-speed, private connection between a physical location and the internet.  
• Broadband internet WAN: Broadband provides a shared connection, so and access to bandwidth is distributed among all users. Speed may be inconsistent due to congestion, and download speed is typically higher than upload speed. This type of WAN is more affordable than DIA WAN but performance is less reliable. 
• Multiprotocol Label Switching (MPLS) WAN: MPLS is a networking technology that routes traffic using the shortest path using labels to control where the traffic flows. It can be inefficient as traffic is routed through a central switch, and not through the internet. It is comparable to extending a local area network environment by laying site-to-site leased lines. 
• Software-defined (SD) WAN: A software platform is used to manage the entire network infrastructure, allowing for the physical appliances to be replaced. Organizations can leverage a mix of different WAN connections and optimize bandwidth flow to balance cost with performance. 
• Cellular and Satellite WAN: Wireless technologies have made it possible to distribute traffic over cellular and satellite networks to provide WAN connectivity in remote locations. They typically run on 4G LTE or 5G mobile networks.

Key Architectural Components of a WAN

The exact design of your WAN architecture will vary based on your business requirements and the type(s) of WAN in use. However, seven architectural components are essential for WAN implementation: 

Architectural Components of WAN

1. End devices

End devices are computing systems that are being connected through wide area network technology. These can range from user-facing interfaces like mobile devices, PCs, and industry-specific workstations to servers, data centers, and mainframes. A LAN groups together end devices in one location, and multiple LANs connect via a WAN. The location and nature of the end device will help you determine the type of WAN technology to use. 

2. Customer premises equipment (CPE)

While most of the networking infrastructure used in WAN is owned by the carrier or service provider, CPE is owned by the enterprise and sits in your local environment. Different types of CPE are used to improve network performance and align the infrastructure with business needs. Examples of CPE include telephones, routers located in your office space, physical firewall appliances, virtual private network (VPN) hardware devices, and set-top boxes. Keep in mind that the WAN provider may assist you with CPE management and maintenance as well. 

3. Access points and routers

While access points and routers technically fall under CPE (as they are located within the LAN environment), they deserve special mention as indispensable architectural components of WAN. a router is your core LAN hub and manages data flow to and from your end devices. Modern routers also have built-in modems, which means that they can receive connectivity signals from the external network and relay it to end devices from a singular appliance. 

Access points are a staple of enterprise WAN architecture. It lets you extend the wireless coverage of your local area network so that you can group hundreds or thousands of end devices spread across a massive office campus into a single LAN. Once again,  access points and routers are both considered to be CPE. 

3. Network switches

Network switches (also part of your CPE) sit between your access points and routers and the end devices to which they are connected. They forward data packets coming through the external network and regulate how they are distributed across your various end devices. Switches can exist in multiple layers, and their job is to ensure that every device gets the bandwidth it requires for optimal performance. In an SD-WAN environment, the network switch system exists purely in software format so that you can programmatically configure how switches are turned on/off and managed. 

4. Local area network (LAN)

LAN is a key architectural component of a wide area network. All the components we discussed so far (end devices, CPE, access points, routers, and network switches) are part of your local area network environment. LAN can comprise just two devices in a consumer-grade use case – a mobile or laptop and the router + modem combination. On the other hand, an average office campus will have thousands of end devices and well-articulated network topology of CPE, access points, routers, switches, etc., which together form LAN. A WAN connects two or more LAN environments. 

5. Connecting media

The connecting media carries data packets in a WAN mesh architecture to and from different LAN components. There is a wide variety of media to choose from when setting up your WAN, including traditional MPLS lines, fiber optic cables, the cellular (3G, 4G, or 5G) spectrum, and satellite connectivity. A complex enterprise WAN architecture will rely on multiple media to connect end devices with the internet. For example, MPLS lines are best suited to LAN environments in close proximity, 4G enables high-speed connections in remote environments, and satellite connectivity is used for security-sensitive applications. 

6. Metropolitan area network (MAN) – optional

A metropolitan area network or MAN is an optional component of WAN architecture. Instead of directly connecting two or more LAN environments, you can choose to connect LANs within a relatively small radius using a MAN. A wide area network or WAN is created when multiple MANs are interlinked. MANs are often implemented in public sector use cases, where it is necessary to connect schools, colleges, hospitals, and other institutions in the same city using a single secure network. 

7. Unified management portal – optional, but recommended

A unified WAN management portal is becoming increasingly commonplace in enterprise WAN implementations. This is because WAN can be difficult to orchestrate and manage, with each LAN hub responsible for network management for its own location. A unified portal (preferably on the cloud) gives you holistic visibility into network operations and allows you to configure bandwidth capacity, speed, performance, and security mechanisms. One of the biggest advantages of SD-WAN is that it makes it easier to deploy WAN management portals and streamline network governance for the enterprise.

Best Practices for Implementing and Managing Wide Area Networks

In 2021, the global enterprise WAN market was worth a median $59.2 billion, according to TeleGeography. 60 percent of this is attributed to MPLS and MLPS access loops, but MPLS revenue is expected to decline as SASE and SSE technologies improve. As enterprises look at refurbishing their network environment in the next few years, here are 10 best practices to remember. 

WAN Management Best Practices

1. Configure your wide area network for wireless connectivity

Enterprise connectivity must support wireless connections as a productivity staple. Employees working a hybrid model will bring their laptops and smartphones to work, which requires a wireless WAN connection. Open office layouts without fixed desks and conferencing spaces also need wireless connectivity. IoT is another use case that relies on powerful wireless WAN infrastructure. You can achieve this by installing a cloud-based WAN management platform and strategically placing access points. 

2. Deploy a “hardware-lite” WAN architecture

As your digital maturity increases (particularly in response to the pandemic), there is a very real risk of hardware sprawl. For example, you can add on new access points to support a change in your office layout. Newer hardware appliances may strengthen network security. After some time, it becomes difficult to maintain an inventory of your WAN architecture, leading to bloated costs and inefficiency. You can address this by keeping the hardware components of your WAN architecture to a bare minimum and opting for software-based components instead. 

3. Carefully assess your options before choosing a WAN provider

There are several options when it comes to choosing a partner for WAN implementation. You could work directly with the supplier of WAN hardware appliances and set up your own environment. Your existing telecom carrier may also have a WAN offering. The decision will depend on the availability of in-house resources and WAN type. 

4. Set up multiple layers of failsafe mechanisms

Since network connectivity forms the backbone of an enterprise, you cannot afford extended downtime or poor performance. That’s why failsafe mechanisms and backup WAN infrastructure are as important as your primary connection. Ideally, the failsafe mechanism should have a different underlying technology than the primary WAN – for example, you can have an SD-WAN set up as a backup to MPLS and a 4G network to fall back on in case both fail. 

5. Leverage SD-WAN to make your network carrier-agnostic

It is a good idea to gradually decrease your dependence on a single telecom carrier and make your enterprise network infrastructure carrier-agnostic. If one carrier fails to perform as per expectations (due to adverse market conditions, regulatory changes, acts of God, etc.), you can scale your network without interrupting business continuity quickly. 

6. Develop a WAN security strategy

By its very definition, WAN exposes your local area network to wider access. This can introduce new security vulnerabilities. Begin by assessing the risk level of each component LAN environment, its devices, and applications. Next, strengthen localized security measures, configure your unified portal to be accessible by only authorized users, and implement network access control. 

7. Take advantage of WAN optimization technologies

There are several WAN optimization technologies that can help you extract more value from your network investments. This includes data compression, which shrinks network packets to lower bandwidth consumption, and data deduplication. You can also locally deploy tools like Wi-Fi analyzers to distribute available resources among end devices more optimally. 

8. Configure your WAN setup to support multi-cloud environments

A surge in cloud applications is among the top technology trends of 2020-2021, and your WAN setup must evolve in tandem. It is likely that you are using multiple cloud solutions for discrete use cases, which can strain your network infrastructure and impact performance. The WAN architecture should allocate precise volumes of bandwidth and ensure performance thresholds meet the requirements based on the nature of the application and the cloud environment in which it resides.

9. Find the right balance between leased lines and software-defined connectivity

SD-WAN is more affordable than leased lines, but the latter typically provides more reliable and consistent performance. It is advisable to reserve leased line-based WAN for your high-priority applications and mission-critical workflows. SD-WAN can handle ancillary connectivity use cases like guest access, routine file backup, and more.

10. Review your WAN architecture regularly and upgrade with emerging solutions

New network innovations emerge every day that can transform how you connect your enterprise, design the WAN architecture, and orchestrate performance. For example, Juniper and Intel now offer artificial intelligence (AI) enabled WAN solutions that can intelligently automate network processes and provisioning. You can also gain from advanced WAN analytics, a blend of hardware and SD-WAN architecture, and a host of other innovations. Review your existing setup once a year, inventory any sprawl or retirement-ready components, and upgrade with emerging solutions. 

Popular WAN Solutions

You may operate a WAN environment entirely through an in-house team without the support of an external solution provider. Your telecommunication carrier can enable connectivity between multiple locations through leased lines and multiprotocol label switching (MPLS). Consequently, you manage the network in-house. However, there are solutions available to simplify WAN implementation and management: 

Cloud WAN Solutions

AWS Cloud WAN

AWS Cloud WANOpens a new window is a managed service for building, managing, and monitoring global networks. Customers connect to AWS through their local provider and then use the AWS global network to connect their on-premises data centers, branch offices, and cloud resources.

Cisco Meraki

Cisco MerakiOpens a new window is a cloud-first platform that offers scalable, secure, and seamless IT solutions, including SD-WAN and wireless WAN technologies. Meraki includes a dashboard that allows users to manage hybrid and distributed networks from a single interface.

Cloudflare Magic WAN

Cloudflare Magic WANOpens a new window provides any-to-any network connectivity across branch and retail sites and data centers and is available as a physical or virtual appliance. It also includes many security features, including DDoS protection, network firewalling, security service edge (SSE), and zero trust functionality.

Juniper Networks’ Enterprise WAN

Juniper Networks’ enterprise WANOpens a new window solutions offer cloud-based management to provide flexible, automated, secure, and resilient connectivity. Multiple use cases configurations exist, including private WAN backbone, peering, cloud connect, data center edge, and data center interconnect.

Dedicated Internet Access Solutions

AT&T Dedicated Ethernet

AT&T offers three dedicated ethernet solutionsOpens a new window for: MAN connections, WAN connections, and a fully managed, multi-point, and customized network solution. The SLA offers 99.999% availability, and speeds range from 1Gbps to 400Gbps.

Lumen Dedicated Internet Access

Lumen’s DIAOpens a new window offers customers many high-quality, high-speed Internet options, including wavelength or ethernet connections. Speeds range between 10/100Mbps ports to 100 Gbps ports.

NTT DATA Dedicated Access

NTT’s global network connects enterprise companies to the worldOpens a new window . It offers three tiers of Gigabit internet: 1Gbps, 10 Gbps, and 100 Gbps.  Also, NTT promises 100% uptime for its global IP network.

See More: What Is Local Area Network (LAN)? Definition, Types, Architecture and Best Practices

Takeaway

A wide area network or WAN is a critical cog in your IT infrastructure, which is why organizations are investing heavily in WAN technology and updates. A WAN architecture that’s in tune with your business needs will make the most of your network investments. A strong WAN environment can support business processes, drive scalability, and eventually lead to continued growth. 

NETWORKING 101

• • What Is a Computer Network?
  • What Is ARPANET?
  • What Is Network Software?
  • What Is a Local Area Network (LAN)?
  • Wide Area Network (WAN) vs. Local Area Network (LAN): Key Differences and Similarities