Leading SD-WAN providers offer varying capabilities

How SD-WAN technologies differ

In the highly competitive SD-WAN market, suppliers offer leading-edge technologies across a range of branch network requirements. Each SD-WAN vendor has specific areas of strength and may have near-term upgrade plans for specific areas of weakness. This section addresses some key areas of technological differentiation for SD-WAN vendors.

SaaS-based application optimization. As more critical applications move to the cloud, a key differentiator for SD-WAN technologies is how they ensure the quality of remote user experience. SD-WAN providers use a number of techniques to identify and deliver low latency for specific applications. These methods include traffic and application identification, real-time performance metrics, and partnerships with specific cloud and SaaS providers.

SD-WAN management consoles enable IT to set and change application priorities and monitor performance in real time. Each SD-WAN vendor has a different proprietary method for delivering cloud-based application optimization.

For example, Cisco partners with AWS to let enterprises seamlessly add AWS resources to their WAN. Citrix partners with Equinix to provide an SD-WAN offering that reliably connects an enterprise to one of Equinix's 145-plus data centers.

Cradlepoint has partnerships with nine top-tier cloud providers around the world, including AWS, Microsoft Azure and Rackspace. These partnerships enable Cradlepoint to use providers' network orchestration APIs to automate the deployments within data centers.

Riverbed's SteelConnect offers instant and easy provisioning of SD-WAN connectivity into Microsoft Azure cloud networks. This provides one-click connectivity for users accessing Azure applications and data. Silver Peak's EdgeConnect offers First-packet iQ, which identifies applications and web domains based on the first packet received. By applying preset policies, First-packet iQ automatically steers specific, trusted SaaS traffic directly to the internet.

VMware SD-WAN provides policy-aware traffic optimization, including TCP flow optimization, bandwidth aggregation, jitter buffering and dynamic multipath optimization.

Network security. This is a perennial concern for IT departments, and remote-office workers represent a significant security vulnerability and challenge. Security requirements at branch locations can vary widely, depending on the applications, vertical industry, and specific regulatory and compliance requirements.

SD-WAN can be deployed as the security service for the WAN or in combination with other network security elements, such as firewalls at the branch, the data center or in the cloud. IT teams should judge SD-WAN options on the integral security offered in the product -- such as enhanced internet security via a lightweight firewall -- and by the service's ability to integrate with the security products already installed in their organizations.

For example, Cisco has its own comprehensive network security product line. Cradlepoint partners with security vendors, including Trend Micro, Webroot and Zscaler. Silver Peak also partners with Zscaler, as well as Checkpoint, Fortinet and Palo Alto Networks. VMware partners with Palo Alto Networks, Checkpoint, Symantec and Zscaler.

Unified communications. Voice over IP and video traffic require specific network capabilities, such as low latency and minimal packet loss, to deliver a high-quality user experience. SD-WAN lets IT teams prioritize UC traffic over WAN links, monitor UC traffic performance and adjust the network to improve quality according to IT requirements. Each SD-WAN vendor has its proprietary method for application identification and traffic prioritization to enhance UC quality. Some SD-WAN providers have partnerships with specific UC suppliers.

For example, Citrix SD-WAN permits bonding and packet duplication for real-time traffic and quality of service, while selecting the best path. Cradlepoint measures path performance and steers traffic based on policy that ensures real-time applications are always using and are on the best-performing link.

Silver Peak makes real-time applications more predictable by reducing packet loss with packet regeneration and resequencing for out-of-order packets. SD-WAN vendor Talari provides continuous unidirectional measurement, packet replication, congestion avoidance and bandwidth reservation.

Versa features embedded voice and video codec support to provide traffic engineering for unified communications services. VMware accelerates real-time applications by proactively prioritizing traffic, while measuring link throughput, packet loss, delay and jitter.

WAN optimization. SD-WAN technology overlaps with legacy requirements for WAN optimization. WAN optimization is a popular technology used to compress traffic and deduplicate packets, among other techniques, to improve the performance of applications that require large, unencrypted traffic flows over the WAN.

SD-WANs can be deployed with an existing WAN optimization appliance. Or, they can often replace the existing WAN optimization appliance. IT organizations with WAN optimization requirements should evaluate the integrated capabilities of SD-WAN offerings. The SD-WAN services from existing WAN optimization suppliers, including Citrix, Riverbed, Silver Peak and Talari, will have the most mature WAN optimization feature sets. Aryaka also offers integrated WAN optimization functionality with its managed service.

Mobility. For mobile branch offices and truly mobile remote users, 4G Long Term Evolution (LTE) is the preferred option. Many SD-WAN providers offer 4G LTE via a plug-in modem. Cradlepoint is well-positioned to support organizations with SD-WAN and 4G LTE requirements.

Delivery as a service. Many organizations would like to outsource the complexity of selecting, deploying and managing their SD-WAN products. Aryaka and Cisco Meraki are well-positioned as SD-WAN technology suppliers' packaged, easy-to-consume services. Many other SD-WAN offerings can be deployed as a managed service through service providers that use a vendor's technology to underpin their own services.

Service and support capabilities. SD-WAN is a complex, powerful and evolving technology. IT organizations may want or need to rely on the supplier or its partners for assistance in planning, deploying, operating and upgrading the SD-WAN product. IT teams should evaluate SD-WAN suppliers based on their service and support capabilities, as well as the breadth and depth of the supplier's partners -- including value-added resellers (VARs), network integrators, system integrations and service providers -- that can assist with customer or technology issues.

Cisco offers a large group of VARs and system integrators trained to assist customers. Citrix, Cradlepoint, Riverbed, Silver Peak and Talari also have mature network VAR partner programs.

Technology vision. The SD-WAN market is highly competitive, with rapidly evolving technology. In the long-term, SD-WAN products will require a large degree of flexibility, vision and agility by potential suppliers. A couple of key areas of vision include the following:

• the ability to improve the management, security and automatic application prioritization capabilities of the SD-WAN offering;
• an investment in increasing interoperability with installed network products, including firewalls, wireless and IT management systems; and
• the ability to deliver on the vision of an SD-branch with broad network functions, including routing, security, WAN optimization and Wi-Fi, integrated into one package.

Evaluating and selecting an SD-WAN offering is challenging due to the complexity and power of the technology and the breadth of supplier options from which to choose.

Aruba, Cisco Meraki, Cradlepoint, Riverbed and Versa have SD-branch products currently available. Other SD-WAN providers plan to add SD-branch functionality to their products over the next two years.

Long-term viability. SD-WAN providers run the gamut, from the largest networking providers and midsize suppliers in adjacent markets to small startups. The market has already seen consolidation -- the most notable being Cisco's acquisition of Viptela and VMware's purchase of VeloCloud. Doyle Research expects significant market restructuring over the next three to five years.

Despite rapid revenue growth, the market clearly won't support the more than 40 current SD-WAN technology providers. IT organizations evaluating SD-WAN platforms should carefully examine the midterm viability of prospective suppliers.

Buying by subscription. IT organizations are shifting from buying products to buying subscriptions -- often on a per-use basis. The benefits of buying networking by subscription include purchasing and deployment simplicity, bundled support costs and automatic software upgrades to the latest features.

Several suppliers offer SD-WAN by subscription. For example, Aryaka's global SD-WAN is delivered as a service, with pricing by number of locations and bandwidth. Cisco Meraki offers SD-WAN and other network functionality by subscription. Citrix offers customers the ability to purchase its NetScaler SD-WAN appliance with zero capacity and then license the software at specific capacity levels on a periodic basis.

Cradlepoint's NetCloud Solutions bundles hardware, software and services. Users can receive continuous software updates and 24/7 support for one-, three- or five-year terms. Riverbed offers SD-WAN software via monthly subscription by bandwidth capacity. Talari offers SD-WAN by subscription through its partners on a three-year term that's priced by bandwidth requirements.

Managed service options. Many service providers offer the option to outsource SD-WAN technology by delivering it as a managed service. IT organizations should consider the benefits of buying a managed SD-WAN offering. After evaluating their SD-WAN requirements, IT leaders can either select the best SD-WAN technology with a managed service partner or rely on the service provider to select the appropriate technology.

SD-WAN suppliers should have a range of partners to deliver their offering as a managed service. Customers can select between communications service providers and managed service providers, as outlined below.

Communications service providers (CSPs). Companies such as AT&T, CenturyLink, Comcast and Verizon offer SD-WAN as a managed service bundled with their transport services, including MPLS, Ethernet, internet and 4G LTE. These bundled services represent a one-stop shop and enable existing customers to easily migrate to SD-WAN.

Managed service providers (MSPs). Companies like IBM and Hughes Network Systems provide outsourcing for WAN operations for many IT organizations. MSPs don't own their own networks and instead contract with existing CSPs and SD-WAN suppliers to deliver a fully managed service.

For example, Cisco partners with British Telecom and Verizon. Silver Peak partners with China Telecom, Fujitsu, Masergy and NTT. Versa's partners include CenturyLink, China Telecom, Comcast, Singtel and Verizon. VMware partners with AT&T, Sprint and Windstream.

Evaluating and selecting an SD-WAN offering is challenging due to the complexity and power of the technology and the breadth of supplier options. IT pros should carefully evaluate their current branch WAN requirements, applications and near-term evolution to prioritize the key features required by their SD-WAN vendor platform. SD-WAN technology should be easy to integrate into your existing IT networking infrastructure, and SD-WAN providers with broad ecosystems have an advantage here.