Wednesday, 27th May 2020

How Innovative SD-WAN Last Mile Management Can Keep Both Your WAN and Critical Cloud Apps Performing at Their Peak

Enterprise WANs have undergone a major shift over the last five to ten years. By Patrick Vernon, technology writer.

In the past, MPLS (Multiprotocol Label Switching) was the WAN solution for businesses. However, as the 2010s saw an explosion in the popularity of cloud-based apps and services and mobile users, some key flaws in MPLS became apparent. The legacy approach to WAN simply isn’t agile enough to work well in more modern use-cases. This, coupled with the high costs of MPLS bandwidth, has led many enterprises to turn to SD-WAN for their WAN connectivity needs. Not only does SD-WAN enable businesses to benefit from economical Internet bandwidth, it is significantly more flexible and ease to integrate with modern workloads.

However, with any new technology comes new challenges to solve and hurdles to overcome. One of the biggest challenges facing SD-WAN users is how to solve “last mile” problems. The last leg of a data transmission from an ISP (Internet Service Provider) to a site can be a major pain point for enterprises, particularly those with a global reach. Fortunately, modern solutions, such as those found with premium SDWaaS (SD-WAN as a Service) can help businesses solve last-mile problems.

In this piece, we’ll dive into the details of the last-mile, explain the issues it can create for enterprises, and discuss how Intelligent Last-Mile Management (ILMM) can help address these problems.

The last mile explained

To understand why the last mile creates problems for SD-WAN, it is important to conceptualize just what the last mile is. For any Internet data, we can chop the transmission of the packets into 3 discrete parts: the last mile between the sender’s location and their ISP (also called the “first mile” in some cases), the “middle mile” that is the public Internet backbone, and the last mile between the receiver’s location and their ISP. As you’ve likely inferred at this point, the “mile” term is used loosely and we’re really referring to that first and last stretch of communications between customers and ISPs.

SD-WAN’s Last mile problems

So, why does this create challenges for SD-WAN? When you start to think about the variety of geographic locations and ISPs an enterprise WAN may use, the answer becomes clear. Not only does the connection quality and reliability vary from place to place, working with multiple ISPs to resolve connectivity issues can be labor-intensive. This is a shift from the MPLS days where users offloaded these problems to the service providers.

While monitoring solutions can help businesses get ahead of some problems, many are based on ICMP (Internet Control Message Protocol). That is, they basically use ping to check connection presence and quality. This can only do so much, and doesn’t allow for the granular level of monitoring that can enable true proactivity when an application stack begins misbehaving. In a world where critical business gets done using Internet based cloud apps, this can be a real problem for business. If a service is responding to ping, but web connectivity is broken, isn’t it effectively down?

The benefits of intelligent Last-Mile Management

What SD-WAN needed to truly address last-mile problems was a robust, reliable, and global backbone that customers can connect to and solutions built from the ground up to address modern WAN challenges. With premium SDWaaS, users get the benefits of SD-WAN coupled with a cloud-based, SLA-backed backbone that is supported by Tier-1 ISPs. This means that enterprises can depend on the multiple Points of Presence (PoPs) SDWaaS offers to ensure connections are reliable regardless of their location or issues with the local ISP. When you think about how ubiquitous cloud apps and services like Office 365 and G-Suite have become, the performance and productivity advantages this can unlock for users at remote sites with otherwise poor Internet connectivity can be impressive.

However, getting a reliable high-performance backbone in place is only part of truly solving SD-WAN’s last mile problems. Monitoring performance at a granular level helps ensure businesses can be proactive in addressing problems and detect not only blackouts (when service is completely lost) but also brownouts (when there is a degradation in performance). SDWaaS with ILMM a.k.a. Intelligent Last-Mile Management does just this. By leveraging SDWaaS with ILMM, enterprises can ensure rapid responses to outages and performance slowdowns, thereby optimizing overall WAN performance. Some of the specific features of ILMM that make this possible are:

·         Continuous Last-Mile Profiling- Creates a dynamic model of performance on the last-mile. After creating an initial week-long baseline of packet loss, latency, and jitter, ILMM continues to iterate and update this baseline as new information comes in. This helps enable accurate detection of brownouts on the WAN while allowing for expected fluctuations (e.g. a change in traffic based on the season).

·         Infrastructure Service Monitoring- Helps identify outages in various network services using protocols like ICMP, DNS, HTTP, etc. This is particularly useful for cloud applications. If a given app isn’t responding to HTTP, action can be taken to resolve the problem immediately as opposed to waiting for ping to time out.

·         Pinpoint Identification- Allows enterprises to stop finger pointing between ISPs and their customers and reduce time to resolution. Testing is performed inside and outside of the SDWaaS tunnels, helping isolate problems to their true root cause.

These features of ILMM, combined with other performance-enhancing features like self-healing and Forward Error Correction (FEC) help make SDWaaS an ideal WAN solution for many modern enterprise WAN use cases.

SDWaaS with ILMM solves SD-WAN’s last-mile problems

As we have seen, the last-mile created a number of challenges for SD-WAN. These challenges required a two-pronged solution to truly resolve the problems and increase performance. By adding ILMM to a robust global backbone, SDWaaS solves SD-WAN’s last-mile problems and helps enterprises boost WAN performance.



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