With SD-WAN on the cards, is there still a case for MPLS? (Reader Forum)

In recent years, there’s been a lot of chatter around software-defined wide area network (SD-WAN) services. The SD-WAN tools and software market is, in fact, expected to hit the $4.6 billion mark by 2023, representing a growth rate of 34% CAGR according to a recent report by Futuriom.

There is, of course, a perfectly plausible reason behind the hype. As enterprises move their IT and networking operations to cloud infrastructures like never before, the demand for agile, high-performance and secure connections to cloud applications follows — that’s where SD-WAN can help.  

The rise of SD-WAN  

SD-WAN, as the name suggests, is not a network infrastructure, but instead a software product that acts as an overlay for a company’s existing network solution — i.e. MPLS, Broadband Internet, Mobile 4G LTE, etc. But because SD-WAN is a virtual solution, it is not dependable on the underlying hardware, making it extremely flexible as a result. If the current network traffic shows signs of congestion, SD-WAN intelligently re-routes to the best path in real-time.   

This also allows for greater speed, as SD-WAN has, additionally, the capacity to handle multiple high-bandwidth WAN links, as well as for dual service providers, simultaneously — naturally, performance is optimized when bonding different types of connection together.  

In terms of security, it’s safe to say that SD-WAN is secure by design. Encrypted end-to-end tunnels (128 bits and up) are built across the whole network (whether 0% or 100% of it is carried on public infrastructure). 

What this means for MPLS   

Now, often along with conversations around SD-WAN comes questioning about Multiprotocol Label Switching (MPLS) solutions. In essence, MPLS works by placing labels on packets, each label informing where the data needs to travel to. Having predetermined, unidirectional paths between pairs of routers across an MPLS network reduces the processing time at each router — a speed augmentation welcomed by big businesses twenty years ago. 

But today, MPLS is used first and foremost by those who look for scalability. That’s because MPLS allows users to previously set up label-switched paths, combining the advantages of physical circuits that are difficult and expensive to scale, with the cost-effectiveness of pure IP routing. 

MPLS also attracts enterprises for its consistent network performance, guaranteed by using Class of Service classifications applied to packets. If a link is congested, it diverts less urgent traffic onto slower routes, meaning when networks are congested, the user experience does not suffer in turn. Furthermore, this sophisticated traffic engineering enables traffic to be sent over non-standard paths, reducing latency and congestion on the paths that have just been avoided as a result of traffic engineering. 

Additionally, MPLS provides improved bandwidth utilization by putting different kinds of traffic on the same link – in the same way that high priority traffic can borrow capacity from lower priority streams whenever required, sudden bursts of bandwidth in lower priority traffic can use capacity from higher priority services out of use if need be. 

SD-WAN vs. MPLS 

Now, you must be wondering: With so many benefits from MPLS connectivity, why should companies move away from the technology? The problem is, MPLS was an adequate solution for yesterday’s challenges, but not today’s. Businesses have typically preferred MPLS, as it is essentially a private network, and therefore, considered reliable and secure. But the fact that it is a company-exclusive link bought from a carrier also makes it far more costly than sending traffic over the public Internet. For organizations currently working remotely, MPLS becomes prohibitively expensive, as the streaming of videos or other multimedia content requires significantly high bandwidth.   

It is also difficult to find MPLS service providers who offer coverage globally or in small locations, making it challenging for companies expanding into new markets. Even if service providers do offer MPLS in those scenarios, there’s only a few who will additionally provide failover to an alternative network link in case the primary connection is disrupted. Limited uptime in today’s digital landscape can pose a powerful threat to companies.  

Last but not least, MPLS is less secure than SD-WAN. That’s because with SD-WAN, customers have full control and visibility over their network connectivity, just like any modern application. Having access to network insights in real-time helps future-proof your business network by allowing your IT team to not only identify a threat more quickly, but also respond accordingly as a result.  

For two decades, Multiprotocol Label Switching (MPLS) has been the go-to network solution for organizations looking for reliable connectivity. It was designed in an era when branch offices sent traffic back to a main headquarters or data center to offer a stable, dependable connection — and it did, for a time.

Yet the fact remains that MPLS no longer meets all the requirements of today’s enterprises working to an unprecedented global scale, generating high volumes of WAN traffic that result from SaaS applications and cloud adoption. As a result, a lot of companies are combining MPLS with Internet local break-out to enhance their network performance and reduce MPLS costs. Why not get best of both worlds and use SD-WAN and full internet connectivity? 

SD-WAN presents a flexible option for those looking for an alternative to MPLS or hybrid network configurations. By providing multiple high-bandwidth underlay connections simultaneously, may it be MPLS and internet, wireless, SD-WAN offers a faster, more cost-effective solution when compared to MPLS. 

What comes next?  

SD-WAN’s ability to handle different network functions reduces both hardware and operating costs. Support for multiple underlay WAN links increases reliability and enables bandwidth aggregation as well as traffic segregation. Intelligent routing allows for network optimization. Cloud-based management makes it easier to deploy and administer network devices. These are all necessary first steps that allow for the next big thing in network connectivity: wireless connectivity, supported by SD-WAN.  

Wireless edge solutions add cellular links as a connection option between the diverse types of underlay network connectivity, to create a more reliable WAN — this is the foundation for Wireless WANs. And the network intelligence at the core of SD-WAN makes switching between links, segregating specific traffic types or quickly opening a new business location almost effortless. 

Wireless connections bring increased diversity, greater network agility and broader reach to enterprise networks. In other words, it expands the reach of the enterprise network to the places, devices and people where work is actually happening.