VeloCloud Dynamic Multipath Optimization - Technology …

1 WHITE PAPERVeloCloud Dynamic Multipath OptimizationPage 1 White PaperVeloCloud Dynamic Multipath OptimizationThis document discusses the key functionalities and benefits of VeloCloud Dynamic Multipath Optimization (DMPO) that assures enterprise and cloud application performance over Internet and hybrid PAPERVeloCloud Dynamic Multipath OptimizationPage 2 VeloCloud Networks , Inc. is the Cloud-Delivered SD-WAN company, a Gartner Cool Vendor 2016, the Frost & Sullivan Product Leader in the SD-WAN Solution Market 2016, and a Best of Interop and Best of VMworld winner. The company simplifies branch WAN networking by automating deployment and improving performance over private, broadband Internet and LTE links for today s increasingly distributed enterprises. VeloCloud SD-WAN includes: a choice of public, private or hybrid cloud network for enterprise-grade connection to cloud and enterprise applications; branch office enterprise appliances and optional data center appliances; software-defined control and automation; and virtual services delivery.

2 VeloCloud has received financing from investors including NEA, Venrock, March Capital Partners, Cisco Investments and The Fabric, and is headquartered in Mountain View, Calif. For more information, visit and follow the company on Twitter 2017 VeloCloud NETWORKS, INC. ALL RIGHTS 3 DMPO Key Functionalities 3 Continuous Monitoring 3 Dynamic Application Steering 4On-demand Remediation 5 Application Aware Overlay QoS 6 Business Policy Framework and Smart Defaults 11 Traffic Class (Priority and Service Class) 11 Network Services 11 Link Steering 12 DMPO Real World Results 16 Secure Traffic Transmission 17 Ports Used 17 Summary 17 WHITE PAPERVeloCloud Dynamic Multipath OptimizationPage 3 IntroductionVeloCloud Cloud-delivered SD-WAN solution enables Enterprise and Service Pro-vider to utilize multiple WAN transports simultaneously, maximize the bandwidth, while ensuring application performance.

3 The unique Cloud-Delivered architecture offers these benefits for on-premise and cloud applications (SaaS/IaaS). This re-quires building overlay network, which consists of multiple tunnels, monitoring and adapting to the change in the underlying WAN transports in real time. To deliver a resilient overlay network that takes into account real-time performance of WAN links, VeloCloud has developed the Dynamic Multi-Path Optimization (DMPO). This document explains the key functionalities and benefits of Key FunctionalitiesDMPO is used between all of the VeloCloud components that process and forward data traffic: VeloCloud Edge (VCE) and VeloCloud Gateway (VCG). For connectiv-ity within Enterprise locations (branch-to-branch or branch-to-hub), the VCEs es-tablish DMPO tunnels between themselves. For connectivity to Cloud applications, each VCE establishes DMPO tunnels with one or more VCGs.

4 The four key DMPO functionalities are discussed Monitoring Automated Bandwidth DiscoveryOnce the WAN link is detected by the VCE, it establishes DMPO tunnels with one or more VCGs and runs bandwidth test with the closest VCG. The bandwidth test is performed by sending short burst of bi-directional traffic and measuring the received rate at each end. Since the VCG is deployed at the Internet Points of Pres-ence (PoPs), it can also identify the real public IP address of the WAN link in case the VCE interface is behind a NAT or PAT device. Similar process applies to the private link. For the VCEs acting as the hub or head-end, the WAN bandwidth is statically defined. However, when the branch VCE es-tablishes DMPO tunnel to the hub VCEs, the bandwidth test procedures are similar to those between the VCE and the VCG on the public Path MonitoringDMPO performs continuous, uni-directional measurements of performance met-rics - loss, latency and jitter of every packet on every tunnel between any two DMPO endpoints, VCE or VCG.

5 VeloCloud s per-packet steering allows independent decisions in both uplink and downlink directions without introducing any asymmet-ric routing. DMPO uses both passive and active monitoring approaches. When user traffic is present, the DMPO tunnel header contains additional per-formance metrics including sequence number and timestamp, thus enabling the DMPO endpoints to identify lost and out-of-order packets, and calculate jitter and latency in each direction. The DMPO endpoints communicate the performance metrics of the path between each other every 100 ms. When there is no user traffic, an active probe is sent every 100 ms and, after 5 minutes of no high priority user traffic, the probe frequency is reduced to 500 ms. This comprehensive measurement enables the DMPO to react very quickly to the change in the underlying WAN condition, resulting in the ability to deliver sub-sec-ond protection against brownout and blackout in the PAPERVeloCloud Dynamic Multipath OptimizationPage 4 Dynamic Application SteeringApplication-aware Per-packet SteeringDMPO identifies traffic using layer 2 to 7 attributes, VLAN, IP address, proto-col, and applications.

6 VeloCloud performs application aware per-packet steering based on Business Policy configurations and real-time link conditions. The Business Policy contains out-of-the-box Smart Defaults that specifies the default steering behavior and priority of more than 2500 applications. Customers can immediate-ly use the Dynamic packet steering and application-aware prioritization without having to define policies. Throughout its lifetime, a single traffic flow can be steered onto one or more DMPO tunnels, in the middle of the communication, with no impact to the flow. A link that is completely down is referred to as having a blackout condition. A link that is unable to deliver SLA for a given application is referred to as having a brownout condition. VeloCloud offers sub-second blackout and brownout protec-tion. With the continuous monitoring of all the WAN links, DMPO detects brown-out or blackout condition within 300-500 ms and ,immediately steers traffic flow to protect the application performance, while ensuring no impact to the active flow and user experience.

7 There is one minute hold time from the time when the link brownout or blackout condition is cleared before DMPO steers the traffic back onto the preferred link if specified in the business learning enables application steering based on first packet of the ap-plication by caching classification results. This is necessary for application-based redirection, redirect Netflix on to the branch Internet link, bypassing the DMPO tunnel, while backhauling Office 365 to the Enterprise regional hub or data : Smart Defaults specifies that Microsoft Lync is a High Priority and is a Real-Time application. There are two links with latency of 50 ms and 60 ms, respec-tively. All other SLAs are equal or met. In this scenario, the DMPO will choose the link with the lowest latency, link with 50 ms latency. If the current link to which the Lync traffic is steered to experiences high latency of 200 ms, within less than a sec-ond, the packets for the Lync of the same flow is steered to another link which has lower latency of 60 ms.

8 MPLS Class of Service (CoS)For a private link that has CoS agreement, DMPO can take CoS into account for both monitoring and application steering decisions. SP will guarantee a different SLA for each CoS on MPLS Link. DMPO can treat each CoS as a different link and can take granular application-aware decisions for private link with CoS : For Service Provider (SP) that offers two Class of Services, CoS1 and CoS2, each with a distinct SLA, the link steering decision can be made to use CoS1 or Inter-net, CoS2 or Internet. WHITE PAPERVeloCloud Dynamic Multipath OptimizationPage 5 Bandwidth AggregationFor applications that can benefit from more bandwidth, file transfer, DMPO performs per-packet load balancing, utilizing all available links to deliver all packets of a single flow to the destination. DMPO takes into account the real-time WAN performance and decides which paths should be used for the flow.

9 Additionally, the DMPL performs resequencing at the receiving end to ensure there is no out-of-or-der packets introduced as a result of per-packet load : Two 50 Mbps links deliver 100 Mbps of aggregated capacity for a single traffic flow. Quality of Service (QoS) is applied at both the aggregate and individual link levels. On-demand RemediationIn a scenario where it may not be possible to steer the traffic flow onto the better link, , single link deployment, or multiple links having issues at the same time, the DMPO can enable error correction for the duration of the disruption. The type of error correction used depends on the type of applications and the type of ApplicationsReal-time applications, such as voice and video flows, can benefit from Forward Error Correction (FEC) during periods of packet loss. DMPO automatically enables FEC on single or multiple links.

10 With multiple links, DMPO will select up to two of best links at any given time for FEC. Duplicated packets are discarded and out-of-order packets are re-ordered at the receiving end before being delivered to the final destination. DMPO enables jitter buffer for the real-time applications when the WAN links experience ApplicationTCP applications, such as file transfer, benefit from Negative Acknowledgement (NACK). Upon missing packet detection, the receiving DMPO endpoint informs the sending DMPO endpoint to retransmit the missing packet. Doing so protects the end applications from detecting packet loss and as a result, maximizes TCP win-dow and delivers high TCP throughput during lossy condition. WHITE PAPERVeloCloud Dynamic Multipath OptimizationPage 6 Application Aware Overlay QoSIn the VeloCloud Cloud-Delivered SD-WAN network, the DMPO tunnels are estab-lished between VCE and VCG, or between VCE and VCE.