Tuesday, September 17, 2019

WAN Optimization in the SD-WAN Era Is About a Lot More Than Just Fast Packets

We’re well into the digital era, and time when so much mission-critical business requires reliable and high-performance WAN connectivity. As bandwidth intensive applications like 4K video-streaming and UCaaS continue to grow in popularity, WAN performance will need to be able to keep up. As a result, WAN optimization is a priority for enterprises.

With the increase of SD-WAN adoption, there are a myriad of approaches to WAN optimization. However, few are able to provide a holistic solution that takes into account all the aspects of a modern WAN. On the surface, this is understandable. Properly addressing the challenges of the last mile, middle mile, mobile users, and cloud services is a tall order. Getting packets from point A to point B faster sounds simple, but there’s a lot that must occur “under the hood” to make it happen. 

This is where the benefits of cloud-native SD-WAN, a.k.a. SDWaaS (SD-WAN as a Service), really shine. SDWaaS offers a few fundamental benefits that extend to WAN optimization and enable enterprises to get the most out of their WAN while using a converged platform. Here, we’ll dive into some of the specific and explain how SDWaaS takes a modern approach to WAN optimization. 

How cloud native SD-WAN enables WAN Optimization  

Understanding how SDWaaS is so effective in delivering WAN optimization benefits for the modern enterprise starts with understanding what makes SDWaaS different from other forms of SD-WAN. SDWaaS offers a converged cloud-based WAN infrastructure that delivers not only networking but security. The underlying private global backbone is supported by Points of Presence (PoPs) around the globe and is backed by an SLA. Security features like NGFW, secure web gateway, anti-malware, and IPS are baked-in to the network. 

This all comes together to create a converged global network from one provider, meaning that complex integrations aren’t required to enable optimization. Where on-prem appliance-based SD-WAN would require additional appliances, if it could even address a given challenge at all, SDWaaS delivers WAN optimization as an inherent part of the network. In short, appliance-based SD-WAN is effectively just an overlay while SDWaaS also delivers a cloud-based infrastructure. 

With that understanding out of the way, let’s dive into some of the specific benefits of SDWaaS for WAN optimization. 

WAN optimization for the last mile

The last mile has been one of the more difficult challenges facing WAN engineers for years. Solving for all the problems that can pop up between an ISP and an endpoint can be next to impossible. Cloud native SD-WAN helps solve these problems in a number of ways, including:

  • Intelligent Forward Error Correction (FEC)- Packet loss is one of the biggest issues in the last mile. Lost packets mean degraded performance. Correction packets enable automatic regeneration of lost packets. Additionally, an intelligent algorithm makes it possible to scale FEC down or up depending on the rate of packet loss and network capacity.

  • Packet Duplication- In some cases, packet loss is simply too high for FEC alone to solve the problem. This is where packet duplication comes in. Sending duplicate packets to both links on an active-active connection enables enterprises to address even high packet-loss issues in the last mile.

  • Active-active links- SDWaaS enables multiple Internet links to be used in an active-active HA (high-availability) configuration. Intelligent monitoring software then ensures the link with the least packet-loss is used to route data.

  • Dynamic PoP selection- This feature allows the network to automatically send traffic to the PoP with the lowest latency and dropped packets.

  • TCP Proxy- SDWaaS TCP proxies allow for larger TCP windows, which can inherently improve throughput. Further, advanced congestion control lets enterprises maximize the efficiency of their utilization.

  • QoS- Traffic shaping features like application priority, Policy-based Routing (PbR), and bandwidth throttling allow mission-critical apps to take priority and ensure enterprises get the most important packets to their destination first. 

WAN optimization for the middle mile

While the last mile has been a bane for WAN engineers, middle mile optimizations can go a long way as well. The SLA-backed global private backbone is one of the most obvious benefits of SDWaaS here. The public Internet offers no SLA, but SDWaaS does. 

Further, the full-mesh topology of the PoPs allow for optimized routing of data. While the geographically closest PoP is usually the best option, that isn’t always the case. SDWaaS can account for both situations. Similarly, dynamic path selection is used to measure latency and packet loss across the ISPs that connect the PoPs. The best path is selected based on the data, further improving WAN performance. 

WAN optimization for cloud and mobile

Cloud and mobile are areas where many appliance-based SD-WAN solutions struggle. It is difficult to take an on-prem solution and optimize for cloud and mobile. SDWaaS architecture makes this simpler and enables WAN optimization for the cloud and mobile users.  

For example, in many cases SDWaaS PoPs are in the same datacenters as popular cloud service providers like AWS, Azure, and Google. Since the PoPs reside in the same IXP (Internet Exchange Point), SDWaaS can deliver performance comparable to services like AWS Direct Connect without the additional cost. 

The PoPs also play a key role in optimizing performance for mobile users. Regardless of their location, mobile users are connected to the SDWaaS PoP nearest to them. From there, the same optimizations and security features made possible for office users are available to mobile users. The baked-in SDWaaS security then enables organizations to set granular access controls to limit the resources accessible by a given mobile users. 

SDWaaS enables significant throughput improvements

All these advantages come together to result in one thing: improved throughput across the board. While there are multiple aspects to the modern enterprise WAN, the end goal is still to deliver the best performance possible from your WAN investment. The cloud-native approach plus global private backbone found with SDWaaS makes that possible for today’s WANs. The converged nature of SDWaaS means enterprises can bring their WAN optimization efforts “under one roof” and improve their WAN throughput.