Wide Area Network: The Essential Guide to WAN 

At some point, most businesses are going to want to connect together computers that are on different sites. Today there are a few options for achieving that but a Wide Area Network offers the most reliability, security and greatest speeds. 


What is WAN?

A Wide Area Network (WAN) is a means of connecting computers together across a large geographic area, sometimes spanning multiple locations across an entire country or several countries. These networks are built by connecting computers, often using leased telecoms lines and various protocols to transfer the data. Multiprotocol Label Switching (MPLS) is a common protocol used for this task.


Features of WAN

  • A WAN provides sufficient capacity to connect many computers over a significant area
  • If you need to connect locations over a large geographical area, such as a region or country a WAN allows your other locations to access the same information in real-time
  • Bring together and connect LANs, MANs and other networks together into your WAN to bring a holistic experience
  • Typically built with redundancy and resilience to ensure if there’s a line outage then your end users connected to your WAN aren’t affected
  • Usually proprietary networks for a single organisation


Origins of WAN

The term Wide Area Network is a definition based on the physical area that the WAN covers. The first computer networks were Local Area Networks (LAN) that connected machines on one site, such as in an office or a university department. LANs are optimised for sharing data over relatively small areas and are not ideal for connecting computers over large geographical distances. Therefore, when it came to connecting LANs together, for example, connecting two branches of a business or two universities, a new type of technology was required.

That’s where WANs come in. Today, we can make ad hoc networks using the internet and public cloud services. For example, collaborating with a remote colleague on a document in Google Docs creates a similar effect to a WAN. However, that process is dependent on the cloud provider. If there is a problem with their service, then the process fails. A WAN gives the organisation control over their own platform.

The same naming approach that gave us WAN gives us several others, including the Metropolitan Area Network (MAN), which connects LANs over an area the size of a city, and the Body Area Network (BAN), which is a network of devices worn on the body to monitor health and fitness. Despite the variety of different networks, LAN and WAN are still the most common.


Why are WAN’s so important to businesses?

WANs are important because they allow organisations to connect their disparate business locations via a WAN (wide area network), allowing them to share and access data securely and easily across their sites.


Benefits of WAN

There are many reasons why a modern organisation would need a WAN. A retailer that wants to connect multiple branches, a law firm with offices around the country or a healthcare provider linking several hospitals would all need some kind of WAN to share information. Everything from stock management systems and staff training, to customer order information and patient records can then be made available to every location from a central server. This removes the need to have a separate file server and email server for every location.

In some instances, a specialist network will be required. In the UK, for example, sensitive personal medical data is stored on the Health and Social Care Network (HSCN). This is a very secure network that is built and managed in line with standards set by the National Health Service. Similar networks exist for the research and education sector, emergency services, and so on. These are all WANs, but with special requirements that organisations connecting to them must meet.

All WANs must be secure, of course, and all need to be reliable. WANs connected by leased lines are faster than broadband internet connections, which helps businesses to get things done more quickly. They are also easy to expand if new locations are added to the organisation.


Managed WAN services

An organisation that needs a WAN has two main options: they can manage it themselves, or they can have a third-party manage it for them. The benefit of managing it themselves is that they have complete control over the network. If changes need to be made then they can be made as quickly – or as slowly – as the organisation allows.

However, this freedom comes with significant downsides. Managing your own network means buying – or renting – the equipment, then making sure that it’s working efficiently, that it’s upgraded when necessary and that it’s replaced when it reaches end of life. To accomplish all that you’ll need to hire staff with the necessary skills and have enough of them to maintain a rota in case the network has problems outside office hours. And when a fault does develop, you might get passed around multiple vendors in your search for a fix.

In contrast, a managed WAN is much simpler. Your provider looks after the equipment and they hire the staff and keep them trained in the latest technologies. They have someone on call whenever things go wrong and if there are multiple vendors involved then it’s your provider who will deal with them to resolve the problem.

Perhaps more importantly, your data will be in their data centre. An organisation managing its own WAN might have the central servers in head office, but what happens if there’s a power failure at head office or a fire next door means the building has to be shut down? Disaster recovery plans are complicated enough without having to plan for the WAN being unavailable. Network providers ensure their data centres have backup power supplies and other redundancies that keep the network up and running.

The advantages explain why it’s typically only the very largest organisations that will manage their own WAN, because they have the scale necessary to make it cost effective.

Take a look at our article on the benefits of managed WAN for businesses for more information. 


What is MPLS WAN?

Multiprotocol Label Switching (MPLS) is a data forwarding technology that provides instructions for how to send and receive information across a Wide Area Network. Introduced in the late 1990s, it remains a popular choice of WAN protocol because of its reliability and efficiency.


What is the difference between MPLS and WAN?

One thing people sometimes ask when they begin researching Wide Area Networks is ‘what is the difference between MPLS and WAN?’ However, the question itself is based on a misconception. As described above, MPLS is one of a range of technologies that can be used to run a WAN. The misunderstanding probably comes from the fact that there is a difference between MPLS and SD-WAN, which we will discuss below.


MPLS networks explained

Developed during the 1990s, MPLS has been a reliable technology for the last two decades. When data travels across networks it is broken into ‘packets’ so that it can be sent more quickly through a ‘tunnel’ from one network to another. These packets are then re-assembled at the destination.

Data packets travel across the internet using IP routing. Each packet is sent to a router, which analyses the packet’s header information and then consults complex routing tables to decide where to send it next. This is fine for sending emails but can result in slowdowns for uses like video conferencing. MPLS is faster because each packet is given a label – a ‘forwarding equivalence class’ (FEC) – when it first enters the network. This tells the router not only where the packet is going, but also how it should be handled.

The router can do all of this without performing header analysis and they can route specific FEC types in specific ways. That means, for example, that video conferencing packets can be earmarked for a low-latency route over the network, minimising the risk of dropouts and disruption.

The advantage of MPLS is that it makes it very easy to create a private network for every customer that is safe and secure. A managed service provider with 2,000 customers doesn’t need to have 2,000 networks, they can just use MPLS to create as many as they need.

This works for customers, too. One customer might need several WANs – perhaps one for their network, one for their phone calls and another backup network. MPLS is ideal for this use case.


SD-WAN versus MPLS

MPLS is partitioned from the public internet, which makes it more secure than alternatives. But the downside of MPLS is that it is more expensive than sending traffic over the public internet. Over the last few years, some vendors have argued for Software-Defined Wide Area Networks (SD-WAN) as a cheaper alternative to the previous generation of WANs, typically those that use MPLS. 

SD-WAN is presented as the more ‘modern’ alternative. However, as with any technology, there are benefits and limitations. SD-WAN uses software to create and manage the ‘tunnels’ that transfer data, rather than the usual physical routers and switches. Instead of leased lines, it uses the public internet to connect networks.

Since it uses software to create a virtual network, SD-WAN is very flexible. Adding a new site to the network doesn’t require an engineer to visit the site, install the necessary equipment and then configure and test it. Instead, a pre-configured piece of equipment is sent to the new site and as soon as it’s plugged in, the central SD-WAN controller will add it to the network.

This ‘zero-touch’ deployment is a major benefit of SD-WAN. It not only makes it easy to expand the network but also allows for easy deployment of policy changes and other upgrades. A process that might previously have taken weeks can be completed in seconds. SD-WAN also works particularly well with modern cloud services, which makes it appealing for many businesses.

MPLS originated in an era when the dominant model involved everything going through the data centre which was, appropriately, the centre of the network. Today’s model is different, with workers more likely to be remote or on the move, and often wanting to connect directly to the cloud, rather than to the centre of the network. Finally, SD-WAN also makes it easier to see how the network is being used, which applications are most-used, where the data is going, and so on. This kind of dashboard overview is very appealing to today’s organisations.

However, SD-WAN is not as secure as MPLS and so it requires extra security tools to monitor and protect it. Also, because it is reliant on broadband connection to the internet, it is more easily disrupted by poor performance and outages. Time-sensitive applications that require guaranteed delivery of data packets are still better-suited to MPLS. That’s why many organisations deploy an SD-WAN on top of an MPLS WAN, so that they can get the benefits of things like a dashboard of network performance but have underlying security and reliability to keep the network safe.


MPLS WAN summary

There are plenty of articles online arguing that MPLS is dead, replaced by SD-WAN. This is far from true. Both technologies have their advantages and disadvantages and both have a place in a modern WAN for an organisation that wants flexibility and visibility underpinned by security and resilience.

The right solution for your organisation depends on your needs and organisational structure. It also depends on your appetite for managing these services yourself. Managing your own network can seem cheaper on the face of it, but often just creates stress and distractions from your core business. A managed network provider like Redcentric can carry that load while also delivering a technological solution – or mix of solutions – that meet your particular needs.

At heart, a WAN is just a technology for connecting together two or more local networks – LANs – to enable an organisation to work more efficiently. The technology used to do this is secondary to the overall concept but MPLS remains one of the most popular ways to achieve this goal.

To find out how Redcentric can help your organisation, take a look at our Managed WAN page or get in touch with our team today to discuss your options.

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