Results-Oriented Application Acceleration with FastView Because Every Second Counts Whitepaper

Transcription

1 Results-Oriented Application Acceleration with FastView Because Every Second Counts Whitepaper

2 Table of Contents Executive Summary...3 Why Website Performance Matters...3 What Affects Website Performance...5 Jump starting your website performance with Radware s FastView...6 FastView Performance Features & Benefits...7 Transport Optimization...7 Reducing transferred content...8 FastView Operational Value...8 Seeing the Application Performance Accelerated...9 Summary...10 Smart Network. Smart Business. 2

3 Executive Summary Regardless of which business metric you use to measure your website s success and effectiveness or your enterprise mission-critical applications conversion rates, number of page views, customer satisfaction, abandonment rates or employee productivity; they are all a direct result of your website s performance. Many companies invest a lot of time, effort and resources to improve their website performance. This includes decreasing its overall page weight and number of objects per page, optimizing its code or using a higher bandwidth to connect to the internet. However, site performance is dependent on an end-to-end application delivery chain where each part of the chain must be optimized - from the web application servers, through the networks between the site and the user, and all the way to the various end-user s browsers and clients. In order to provide customers the best online experience, IT must address various aspects that degrade site performance. To effectively address website performance from various aspects including different browser technologies, poor performing WAN connections and ever evolving online applications, a holistic approach is required. This can provide the best web performance optimization (WPO) to any type of client anytime or anywhere. This paper highlights the business motivation as to why organizations must ensure continuous performance optimization of their site and how Radware s FastView technology and application performance monitoring module can effectively accelerate any business. Radware s FastView - a result-driven acceleration technology embedded into the Alteon Application Delivery Controllers (ADC), offers a holistic approach addressing the various aspects impacting web applications performance. Tested on various websites and enterprise web applications, FastView reduces critical seconds of response time for maximal business impact. By optimizing the various elements along the application delivery chain and relieving different bottlenecks in the web application server, network, and the clients browser, FastView provides improved QoE for all types of end users. To help customers measure the web application performance and ensure it meets their expected SLA at all times, Radware also provides a new Application Performance Monitoring (APM) module, enabling a proactive approach for monitoring and maintaining a high SLA of the website and web applications. Why Website Performance Matters Businesses understand that website performance is critical to success. You may recall a time where you tried to access a website and after few seconds of waiting, you lost patience and moved on. This chapter will show how the correlation between website performance and various business metrics, such as number of page views, revenues per user, and customer satisfaction. Many leading web companies have measured different aspects of how website performance impacts business metrics For example: Amazon found that 100ms faster page load time resulted in 1% increase in their online shop sales revenues. A Google study showed that increasing their page load time by 500ms resulted in 25% fewer searches. Fewer searches on Google search engine equates to fewer ads shown (and clicked) - directly impacting their business. Another interesting study, from Microsoft Bing, showed that a 1 second slower page load time resulted in 2.8% drop in average revenue per user and 1.6% drop in end user satisfaction. Smart Network. Smart Business. 3

4 0.0% Delay applied on page load time 500ms 1000ms 2000ms -1.0% -2.0% -3.0% -4.0% -5.0% Revenue Per User User Satisfaction Figure 1 - Page load time delay vs. revenue per user and user satisfaction (source: BING) Even more interesting, Microsoft conducted this study over a period of 3 weeks, showing that the business impact worsened at the end of their test compared to the beginning of it due to users growing dissatisfaction. According to a study by the Aberdeen Research Group, a one second delay in response time, not only decreased page views by 11% and conversion rate by 7%, it also decreased customer satisfaction by a staggering 16%! 0% Page Views Conversions Customer Satisfaction -2% -4% -6% -7% -8% -10% -11% -12% -14% -16% -18% Lost revenues Brand damage More support calls Increase costs -16% Figure 2 - Average Impact of One Second Delay in Response Time (source: Aberdeen Group) By analyzing page abandonment data in more than 150 websites and 150 million page views, Gomez found that an increase in page response time from 2 to 10 seconds increased page abandonment rates by 38%. These observations conclude that there is a clear correlation between a website s response time and its business performance. Whether it is a number of page views, online revenues, page abandonment or customer satisfaction they are all effected and quantifiable per the website s response time. Smart Network. Smart Business. 4

5 What Affects Website Performance Organizations recognize the importance of their website performance in terms of availability, security and response time. However, there are a wide variety of factors that negatively affect website performance and end-user quality of experience spanning from everything between the user s client and browser used, geographic location, the access network through which it is connected, the data center deployment, the content type consumed, the way it is consumed and of course the quality of the application serving the user. Below are the key shifts that impact Website performance: Web content consumption has changed: the content itself has shifted from basic text based web pages to more advanced applications with rich and dynamic content which often include heavier objects such as images, sound, movie clips and heavy graphic ads. HTTP archive, a site that monitors trends in over a hundred thousand websites, demonstrates that not only the average web page weight is growing but also the number of elements per page, requiring the client to open more connections for longer period of times; ultimately straining application infrastructure capacity limits. Total Transfer Size (KB) Dec-10 Mar-11 Jun-11 Sep-11 Dec-11 Mar Number of Requests Per Page Number of Requests Total Transfer Size (kb) Figure 3: Total Transfer Size & Total Requests per page (source HTTP archive, May 2012) The way web content is consumed has also shifted: Users are no longer bound to a company desktop computer connected through a wired dial-up connection at home or at the office. A client can use a new type of browser running on the latest mobile device to connect to the internet through a mobile network with lower capacity and longer round trip times (RTT), as well as through his office Wi-Fi connection with high capacity and short RTT. In addition, enterprises are facing a new trend where employees bring their own devices (BYOD) and need to adopt and optimize their web applications to a growing mix of devices and browsers. Increased latency due to protocol bottlenecks: whether the web application uses TCP or UDP for the transport layer, protocol behavior directly impacts application performance. TCP protocol, the transport layer of HTTP based applications, delivers a significant performance difference when operating over low RTT networks, such as wired DSL connections, compared to lower capacity wireless mobile networks with long RTT, such as, 3G or 4G mobile networks. A user accessing his favorite shopping website from his laptop at home expects the same Quality of Experience (QoE) when accessing the same site on the move from his mobile device. This should not affect the response time. However, even if the website is optimized for mobile devices, TCP protocol may deliver a slower response time and lower capacity when operating over a mobile network. Smart Network. Smart Business. 5

6 Content Caching is not enough: a common method widely used to improve user experience is content caching. This is achieved by bringing the information closer to the user either to a nearby CDN node or to the user s browser cache. According to HTTP archive, 58% of the cacheable content on the sites and pages they ve tested is still not properly marked for caching. Consequently, instead of bringing this content either from a faster source such as the ADC front-ending application server, or from the browser s cache; more content needs to be delivered from the servers to the user. The result is slower web application response time and higher loads on the servers. Cached for a month to a year 8% Cached for over a year 3% Cached for a day to a month 16% Unmarked as cacheable 58% Cached for less than 1 day 13% Short term cache 3% Figure 4 - cache control marking (source - HTTP Archive) Optimized Web Application coding: Good coding practices can greatly improve end user QoE. For example, a web page designed in a way that delivers to the user readable information first, along with the required objects to start displaying the page, will improve the end user s perceived site s response time and QoE. Yet, most organizations can t afford to open their web applications code due to the risk involved and its high cost. Additional good coding practices include building separated CSS files per section in the page and including as many comments in the code. However, such practices increase the number of objects per page and as shown above; already add more delay to the site s load time. Optimizing web application performance will require addressing each of the above challenges simultaneously, per user profile (e.g. device type, browser used etc.) and application. Jump starting your website performance with Radware s FastView Traditionally, improved QoE has been one of the functions the ADC provides. It offers high availability of the application through smart server load balancing and application health-checks to automatically bypass failures and Global Server Load Balancing (GSLB) for inter-site redundancy. Combined with Radware s patented proximity function, it also ensures the end user is served from the closest and least loaded datacenter for better response time. Radware ADC also provides SSL offloading and content compression to further accelerate the performance of web sites. With the evolution of Web Performance Optimization (WPO) techniques, there is more that ADCs can do to accelerate website performance. Radware s FastView is a Web Performance Optimization (WPO) technology integrated into the Alteon ADC platforms which extends the ADC application acceleration offering. FastView offers Smart Network. Smart Business. 6

7 a concerted set of capabilities which significantly accelerate websites and web applications performance while reducing the development and operational overhead in maintaining such optimizations. Steve Souders, a world-recognized specialist in the Web Performance Optimization domain, published a set of 14 golden rules for accelerating websites 1. Radware s FastView technology covers 8 of those 14 rules which are applicable for all users, eliminating the effort required to implement and maintain those best practices in each web application in order to reduce cost. FastView Performance Features & Benefits FastView s set of functions can be categorized into two areas of website performance bottlenecks: it optimizes the transport to overcome WAN latency as well as reduce the amount of content transferred to the end-user. Transport Optimization All WAN connections introduce latency to the communication between the user and the website based on network latency, number of hops (affected by geographical distance and used links) and the quality of the various networks traversed. This latency is multiplied by the number of round trips required to deliver the web application content to the user. There are two ways FastView addresses this bottleneck: reduce the number of round trip required and reduce the latency of the WAN connection. Object combining and in-lining the number of objects per webpage is constantly increasing. A bi-directional TCP transaction (per object) combined with the inherent delay of WAN connections introduces a delay factor which is multiplied by the number of objects in the webpage. Radware s FastView reduces the number of server requests required per page by grouping multiple CSS objects as well as multiple Java Scripts into one object. Further reduction is also achieved with small CSS objects and Java Scripts where the transaction overhead exceeds the size of the object. In those cases FastView embeds these objects in the HTML document, further reducing the number of transactions and the amount of bandwidth required to deliver those objects. Combining and in-lining CSS and JS you can reduce the number of requests per page by 20% to 30% on average, accelerating both pages in first view and in repeated view. Mobile users benefit from the reduced number of connections to a greater extent due to the larger delays introduced by the mobile network. TCP protocol optimizations FastView optimizes the protocol used and makes it more efficient by reducing the latency of the WAN connection. FastView utilizes an advanced algorithm for TCP congestion avoidance, in addition to the set of other TCP protocol optimization RFCs and TCP connection multiplexing (which serves user s TCP connections with existing opened TCP connections between the ADC and the server), all of which are applicable for all users and don t require user cooperation. TCP protocol optimizations implemented in Alteon include: - TCP Selective Acknowledgments Options (RFC 2018, 2883) - TCP Congestion Control (RFC 5681) - Enhanced Loss Recovery using Limited Transmit and New Remo Algorithm (RFC 3042, 3782) Congestion avoidance optimization FastView leverages the Hybla TCP enhancement algorithm, which offers significant performance improvement, especially for mobile users, using networks with higher round trip delays and higher packet loss. This new TCP optimization mechanism provides higher and more consistent throughput, delivering overall faster performance for websites using it. 1 Source of Steve Souders 14 golden rules for accelerating websites and web applications: Smart Network. Smart Business. 7

8 Reducing transferred content The other set of capabilities offered by FastView to accelerate web application performance relates to the amount of information transferred from the servers to the user. Content minification removing any unnecessary content such as comments and whitespaces used by programmers in the Java Scripts and CSS code. Reference URLs embedded in the HTML document or in the code often use absolute reference, taking much more volume than relative URLs. FastView trims URL, further reducing the size of the transferred content. Content minification is another functionality which impacts both first and repeated views. Dynamic Object Caching: a powerful way of reducing the amount of transferred content from the server to the user is not transmitting it at all. FastView includes a new technology which can identify cacheable content even if it is not flagged as cached or missing some of the caching attributes for effective caching. FastView s caching mechanism includes two layers of dynamic object caching: The first layer is content caching in the Alteon ADC by caching objects in the ADC, requests from the browser are answered by the ADC much faster and never reach the server allowing the server to handle other requests faster. Moreover, the embedded ADC s Global Server Load Balancing (GSLB) functionality ensures the user is redirected to the closest and least loaded datacenter and served by the ADC s cache there. Dynamic caching on the ADC combined with GSLB, directly accelerates response time of pages accessed by the user for the first time ( first views ). The second layer is content caching in the end-user s browser: FastView flags objects it classifies as cacheable and instructs the browser to keep them for future use such as repeat views of the same page or even repeat use of objects in other pages of the same site. The benefits of FastView s dynamic object caching is twofold: faster web application response time while offloading the web application servers. Web compression - compress the transferred content size to accelerate Web pages response time, especially for responses to back-end database queries which include a large amount of data. Compression not only improves overall end user response time and productivity but also reduces the size of the replies by up to 90%, resulting in reduced amount of bandwidth consumed. Content compression effects response time of both pages viewed for the first time or in repeat view. Secure Sockets Layer (SSL) offloading terminating SSL sessions in the ADC and offloading this function from the server is vital for accelerating web applications. It enables all of the above functions (e.g. caching, CSS & JS combining etc.) on encrypted traffic. This means that not only the home page of an e-commerce site is accelerated but also the checkout pages which are SSL encrypted. Terminating SSL sessions in an SSL hardware accelerator, which is built into the ADC, also enables faster SSL transaction processing while offloading the server resources, thus reducing the number of servers required to serve the same number of users. FastView Operational Value By implementing industry best practices, FastView delivers comprehensive coverage for various web application bottlenecks, enabling faster web application response time for all users starting at the 1st page visit. Plus, it enables real results in terms of faster time to market and faster web applications for all users anywhere and anytime. Smart Network. Smart Business. 8

9 By embedding FastView technology in the Alteon ADC, enterprises can instantly provide its benefits to all the applications it oversees in a datacenter centric manner, with no change to the web application deployment and with no integration required; ultimately reducing effort, costs and risk. Seeing the Application Performance Accelerated To ensure your Web application performance meets your expectations and consistently delivers the SLA endusers expect, one must gain visibility on both application performance as well as on the actual QoE end users are experiencing. By leveraging Radware s Application Performance Monitoring (APM) module, Web application administrators can gain more control on actions they take to improve their application performance. They are as follows: 1. Measuring the impact of new acceleration technology such as FastView on their Web application performance. With detailed historical performance reports, business results can be cross-referenced with web application performance. 2. Tracking actual end users QoE with a detailed breakdown per real user geo location, real application transactions, real-time error statistics and notifications to proactively respond in real-time to application slowdown. Radware s APM is provided as part of APSolute Vision, Radware s central management system. It doesn t require any integration to the application infrastructure; hence it doesn t introduce any overhead including application scripting, simulating synthetic transaction, etc. The performance measurements are based on real user transactions (as opposed to synthetic based basic read only transactions monitoring) as well as real errors that are captured by an advanced data collection and processed by an analytics engine; part of APSolute Vision, Radware s central management system. The analytics engine provides both a wide variety of granular reports as well as user configurable reports to align performance measurements with specific business goals and metrics. Clients Distributed Monitoring Centralized Reporting Data Center 1 Internet Data Center 2 Cloud Measures application performance in any client, anywhere Collects Application Performance Information in & accross datacenters Detailed reports about Real user experience Actual application SLA Figure 5: Radware s Application Performance measurement methodology Smart Network. Smart Business. 9

10 Radware s APM s Web performance measurements span all applications and servers handled by the Alteon ADC. Furthermore, such measurements can be collected from multiple Alteon devices, providing cross datacenter views of application performance and end-user QoE. This enables faster and accurate troubleshooting and faster root cause analysis in case of application delays. Each transaction measurement data is broken-down into a 3-stage application delivery chain: 1. Server to ADC response time the time spent in the data center. 2. Network time the time it takes for the server response to reach the client 3. Browser rendering time the time it takes the browser to render and present the page Figure 6: Detailed Application performance and user QoE reports This end-to-end application performance monitoring solution captures actual user QoE, based on actual application transaction latency and real time errors providing: The visibility required to continuously ensure that the web applications meet the business SLA An efficient troubleshooting tool for fast and accurate detection of performance issues, all in real time. Simplified deployment, with no dedicated scripts per web application, lowering costs Summary Whether today s internet users use a public website or an enterprise web application, every second counts. For an Enterprise, web applications must meet high performance standards to satisfy their customers. Radware s FastView technology provides a comprehensive solution which handles a lot of the application performance bottleneck in a data center centric simple way. FastView is focused on delivering the most effective application web acceleration for all types of users devices, browsers and WAN connections. With the integrated Application Performance Monitoring module, web application administrators can track their application performance to proactively ensure the fastest performance for maximal business impact Radware, Ltd. All Rights Reserved. Radware and all other Radware product and service names are registered trademarks of Radware in the U.S. and other countries. All other trademarks and names are the property of their respective owners. Smart Network. Smart Business. 10 PRD-FastView-WP /06-US