How SD-WAN as a Service Addresses MPLS Limitations

While MPLS has served enterprises well for many years, it no longer adequately meets the needs of global enterprises. More than 50% of global WAN traffic now reaches the cloud, but MPLS was designed for point-to-point connections, not point-to-cloud and software-as-a-service (SaaS). And MPLS has many other limitations.

[[246799]]

• No. 1 - No single provider can provide end-to-end MPLS services worldwide. A global MPLS network requires a patchwork of service providers. This can cause maintainability issues as problems are fixed and complicates efforts to provide network redundancy.
• No. 2 - MPLS is a dynamic shared medium. While MPLS is traditionally viewed as a dedicated network service, it is actually a shared medium that carries certain risks. Instead, security-conscious buyers will gravitate toward dedicated bandwidth to close this gap.
• No. 3 - Not all "private networks" are secure. If no one provider has an MPLS network around the world, and traffic is only differentiated with MPLS labels, how hard is it to SPAN ports and sniff traffic? Also, if you have to break out cloud/SaaS traffic over the internet, you're opening yourself up to new attack vectors.
• No. 4 - MPLS was not designed for today’s business speeds. Change orders can take weeks and new installations can take months, yet today’s companies need to be able to add locations in days and make service changes at any time.
• No. 5 - Cost imbalance. MPLS pricing is derived from the past when bandwidth demand was a fraction of what it is today, so premium pricing was tolerated. Bandwidth demand is growing at a 26% compound annual growth rate by some accounts, and MPLS is too expensive for everything.

The shortcomings of MPLS force enterprises to consider other options, but these options only solve part of the problem and leave the planning, procurement and management to the enterprise, which complicates the problem-solving work.

Traditional Point Solutions

There are some standard point solutions that customers naturally gravitate toward when they find that MPLS doesn’t meet their needs. Each of the point solutions below – Internet, WAN optimization, redundancy, security, and SD-WAN – can solve some problems, but not all.

(1) Internet. Most organizations consider using the Internet when their bandwidth needs change or when the need for rapid deployment requires finding a way to supplement MPLS. The Internet allows you to gain capabilities that are not possible with MPLS.

While cheap and quick to deploy, WAN internet links are susceptible to latency and packet loss. Stable latency issues have always plagued things like VoIP and prompted latency optimization options at the network and protocol level, but are even more concerning given that companies are now trying to use these links to access mission-critical cloud and SaaS services. The internet lacks stability and does not offer service level agreements (SLAs) across medium and long distances.

The same is true for packet loss. While packet loss is still an issue when applications and services are located on-premises or in certain physical locations, with cloud/SaaS/UCaaS you can place services anywhere in the world. If one of the layers supporting these services is the Internet, end-to-end stability, packet loss recovery algorithms, and protocol enhancements are a must.

(2) WAN optimization. Whether you attempt to change MPLS to meet new requirements or use the public Internet to supplement MPLS, if you want to provide a consistent user experience regardless of where the user is located, you will need to add additional optimization tools to your WAN routing. This will involve a significant capital expenditure investment and leave you with more network resources to manage. Even then, it may not adequately address performance issues, especially in international situations.

(3) Redundancy. Given that you want to use the Internet to support links for mission-critical applications, you have to build in some redundancy. We’re not just talking about multiple devices here, but the ability to use dual links at the edge and in the core of the network. Redundancy should also include diversity of service providers and the ability to route on both sides of the earth—in other words, the best possible redundancy of submarine and terrestrial cables. There should also be software-defined capabilities to enable further redundancy, such as point-of-presence redundancy and data center redundancy.

(4) Security. IPSec is a must, not only at the edge but also in the core or middle mile. You must also demonstrate this by deploying and managing a host of common network security tools to ensure that no one can find a way into your network through the WAN.

(5) SD-WAN. Software-defined WAN is very popular nowadays, but most SD-WAN tools only provide software overlay and use the Internet for long-distance transmission. Therefore, although SD-WAN can use the Internet to supplement MPLS and formulate policies to clarify how to handle traffic, all the above-mentioned problems still exist.

If you only have a few locations and they are in the same region and you don’t use a lot of cloud and SaaS services, this type of SD-WAN may be the answer you’re looking for. However, if you are a large enterprise with many geographically distributed locations and use (or consider moving to) many cloud services, a DIY SD-WAN kit will leave you wanting more, not to mention the hassles of integration.

So what makes a good WAN?

There needs to be a better way to solve all of these problems. An ideal WAN should:

• Optimize Transmission Control Protocol (TCP) - This has a triple impact on your traffic. Packet payloads are larger, packets are tighter, throughput is faster, and your first byte is delivered faster. TCP optimization is a must for any data application.
• Use a complete set of SD-WAN algorithms to address packet loss recovery issues, not just one or two.
• Provides optimal flexibility to move, add or change sites, and quickly disconnect.
• Provides built-in redundancy at all layers of the infrastructure. Optimizes bandwidth, thereby optimizing the money spent on the network.
• Provides 24/7 support.
• Provides detailed visibility through the portal, not only into/out bandwidth, but also into application-level usage, performance metrics and statistics.
• Provide a throat block for all these services to avoid mutual finger pointing.

All of this points to the as-a-service provided by SD-WAN. Unlike point solutions, SD-WAN as a service frees you from having to think about how to: accommodate high-growth bandwidth; support enterprise digital transformation; and migrate your services to the cloud. It simplifies the network and frees up IT resources while focusing on opportunities to grow your business.

Now is the age of SD-WAN, and the only one that can meet your changing needs is SD-WAN as a Service.