Titolo del paragrafo. Titolo del documento - Sottotitolo documento The Benefits of Pushing Real-Time Market Data via a Web Infrastructure

Transcription

1 1 Alessandro Alinone

2 Agenda Introduction Push Technology: definition, typology, history, early failures Lightstreamer: 3rd Generation architecture, true-push Client-side push technology (Browser client, Application client) Network: bandwidth control, adaptive streaming Server-side technology Case studies: trading platforms Benefits Delivery Vs. Requirements? 2

3 Introduction The Internet provides an opportunity for financial institutions to reach a wider market audience, to offer services and generate increased revenue as a result. But services using real-time market data distribution via Web must provide a high quality of service approaching those of existing professional solutions on the trading floor. With features such as: Real-time delivery and low latency. Reliability. Scalability. Secure access control. But with the lower cost point provided by Internet distribution. 3

4 Push: Definition Pull: Casella The di testo classic Web mechanism. The client makes a synchronous request to the server to get data. Each server response corresponds to a client request. Push/streaming: The asynchronous and real-time paradigm. The client makes a single request (to start the push session), the server then sends a continuous flow of responses (streaming). The client receives asynchronous data at the discretion of the server. 4

5 Push: Typology of different architectures Phases of the push paradigm: Casella Notification: di testo notification message that some content has changed. Delivery: receipt of new content. Push typology: Polling Notification: absent Delivery: synchronous (pull in polling) Page refresh either manual or automatic Smart pull manual Notification: asynchronous Delivery: synchronous (pull manual) The user receives an update regarding new content and manually downloads it. Smart pull automatic Notification: asynchronous Delivery: synchronous (pull automatic) The system receives an update regarding new content and downloads it. True push / streaming Notification: absent Delivery: asynchronous The system receives directly in real-time the new content. 5

6 6 Push Technology: History First Generation ( ) Casella Spring di testo 1996: PointCast was released. Sep. 1997: W3C organised a workshop regarding push. Analysts affirm that push is a killer application and will be one of the principle means in the future to provide. Was also the period when intelligent agents were also fashionable. About 30 players tried the push market (PointCast, Netscape Netcaster, Microsoft IE Active Desktop, Marimba Castanet, ). At the end of 1997 began the decline of push. Second Generation (2000) PointCast closed. Re-launch of some products from the first generation (BackWeb, Marimba, etc.) but with greater attention to bandwidth problems. The success of on-line trading and the beginning of streaming push, with custom solutions for real-time push of stock quotes. Third Generation (2003) May 2003: Lightstreamer was introduced on the market.

7 Push: Why earlier generations failed? Why the first generation failed? Casella Internet di testo bandwidth was saturated by excessive amounts of transmitted data. Often required software installation on the client PC. There was never really a need to get to the office in the morning and find the PC desktop full of new pages that you never had time to read. Why the second generation was never diffuse? Often the solution was really polling and not true push. They could not get through intermediate proxies and firewalls. The Internet bandwidth of user s PC was still getting saturated. Blocks with user navigation because the multiple push windows used all the browser connections. Classic network congestion problems caused data ageing of pushed data. It was necessary to download onto the user s browser an applet ActiveX or plug-in. Which complicated the user support and increased maintenance cost because of lack of homogeneity with the website HTML content. 7

8 Push: Existing limitations to overcome Previous solutions presented several problems and limitations that had to be solved for push to be effective. Requirements when defining a 3 rd generation True push : Need a real push not simulated (polling, refresh, ). Overcome the problems in passing data through proxies and intermediate firewalls. Eliminate the risk of saturating the Internet bandwidth of users PC. Eliminate the blockages of users navigation (because the multiple push windows use all the browser connections). Avoid Internet network congestion causing data ageing. Eliminate the need for the users browser to require an applet, ActiveX control or plug-in to be downloaded. 8

9 Lightstreamer: 3 rd Generation Push Architecture Every cluster node is a high-performance process composed of three modules: Lightstreamer Server: the push engine; maintains the HTTP/HTTPS connections with the clients and distributes the data, filtering them according to available bandwidth and allocated frequency. Lightstreamer Metadata Adapter: the plug-in module that integrates Lightstreamer Server with existing back-end systems, it obtains the metadata of the push sessions (user authentication, description of information categories,...). Controls the users subscription rights of data published via the data adapter Lightstreamer Data Adapter: the plug-in module that receives the data flow from the information provider and passes it to Lightstreamer Server. The items are published through the data feed for subsequent subscription by the user, only to the items required and according to the individual rights defined by Metadata Adapter. 9

10 Lightstreamer: True push The browser or client application maintains a single permanent HTTP Casella or di testo HTTPS connection with Lightstreamer Server 10 It passes through all proxies or firewalls both on client and server side. Only standard web format data is passed through the channel, without the need for tunnelling techniques. Only one connection is required to support a push session with windows and multiple frames, using multiplexing techniques. To use more connections would signify a navigation block for the user (browsers in general will only provide an average of 4 contemporary connections). With HTML clients, the browser executes the presentation logic coded in the JavaScript libraries supplied with Lightstreamer. These are provided by any standard Web server (pull) as with any other web page on the site (from Lightstreamer Server only live data is sent). With custom clients there is a Lightstreamer Client API.

11 11 Lightstreamer: HTML Browser Client Push Advantages of a push solution based purely on HTML & JavaScript: No waiting to download external components and no support head aches. No waiting for Java Virtual Machine initialization and no compatibility problems (Java Sun, Java MS, ). No security risks or firewall blockages. No need to simulate the HTML web site layout with Java, reducing cost. Lightstreamer sends the browser a Instant live data! initializing stream of updates, which are a push session it s s as visualized in real-time from pure quick as loading any common HTML web page! JavaScript code, which guarantees compatibility with all browsers.

12 Lightstreamer: Application Client Push Casella Apart di from testoproviding a live front-end for HTML browsers, Lightstreamer can also enliven client applications implemented with any technology through the Java API client libraries. Lightstreamer s powerful mechanism to control bandwidth, frequency and multiplexing is indispensable to any client application which needs live data. Application clients can provide an advanced manipulation of pushed data (real-time charts, special animation, ). 12

13 Network: Bandwidth control Filtering: Many types of data that require pushing can have Casella filtering di testo algorithms applied. As a function of frequency: In cases where storing historic market data is not required, it is futile to send updates with a frequency that is too high, because the changes can not be detected by the human eye. As a function of allocated bandwidth: If the number of updates produced by the source exceeds a determined bandwidth for any individual user, their data then begins to be filtered. Lightstreamer provides the possibility to allocate for each user a maximum bandwidth and a maximum data rate frequency, which guarantees: That the allocated bandwidth is never exceeded; That the consistency of the visualized data is never violated, even with the loss of updates through filtering. Advantages of bandwidth control: Server side: Simple to calculate the required bandwidth connectivity required by the Server. Client side: Non saturation of the bandwidth provided by the users Internet connectivity. 13

14 Network: Adaptive streaming Lightstreamer automatically compensates for network congestions and slows or suspends the data delivery via adaptive filters based on heuristic algorithms, until bandwidth becomes available. When the channel become available again, the user does not receive a burst of obsolete updates, but immediately starts to receive the new data (data aging is avoided). Because Lightstreamer operates at TCP/IP level, data is aggregated efficiently into TCP packets, with direct control over the number that are sent and over delays. High quality push sessions can be achieved with less than 5 kbps. 14

15 Server Side: Implementation Lightstreamer Server was implemented in pure Java as a standalone Casella di process testo with advanced optimization techniques, to provide maximum deployment flexibility. read/write multiple locks thread pooling and array pooling string reimplementation multi-stage data filtering JMX compliant for QoS administration Benchmark performance Thousands of concurrent users can be supported by a single CPU. Clustering Clustering is supported though the use of common load balancing techniques to scale in parallel many CPU s and Lightstreamer instances. 15

16 Case Studies: Trading platforms - IntesaTrade IntesaTrade T 3 ( T 3, an innovative platform for online trading from IntesaTrade (Intesa Bank Group, Italy). It uses Lightstreamer as a push server for Financial market data via Internet. All the windows of this Java application are supplied with live data from Lightstreamer. It supports the push of many different kinds of data (stock quotes, multi-level books, watchlists, portfolio contents, order monitors, news, best/worst performers, etc.) 16

17 Case Studies: Trading platforms - Patsystem Patsystems TradeMark & J-Trader ( J-Trader is Patsystems Java-based feature-rich front-end application for online, multi-exchange, real-time access to futures, options and forex markets. TradeMark is Patsystems next generation, high capacity trading platform for derivatives market. It uses Lightstreamer as the push server for efficient, high capacity distribution of Trademark Financial market data. 17

18 Case Studies: Trading platforms - Dene Dene GATE ( GATE is Dene s FX market data distribution system. It uses Lightstreamer as the push server to supply FX market data to an HTML browser used as a thin client trading front-end. 18

19 Web Based Trading 19

20 Professional Trading Solution 20

21 Benefits: Saves Bandwidth Due to a multi-plexed architecture only one connection is required to update multiple windows, the utilized bandwidth is managed by Lightstreamer so that real-time updates can be maintained with connections as low as 5 kbps. Simplifies Security Issues Data passes through any proxy or firewall by implementing real-time data streaming over HTTP/HTTPS using HTML & JavaScript. It does not rely on Java applets or ActiveX which are blocked by some security policies. Reduces Cost Since no Java applets are used to implement data streaming there are no major modifications or skills required to model the HTML web pages with Java thus reducing the ongoing maintenance overhead through layout homogeneity. Builds On Existing Architecture Lightstreamer is flexible; runs on JVM, and integrates with any web server, using adapters to 'plumb in' the information feed and metadata configuration. It is also scalable and highly available by using common load balancing techniques that can handle many thousand concurrent connections. 21

22 Delivery Vs Requirements: Secure access control. Reliability. Scaleability. Lower Cost 22

23 Contacts: Alessandro Alinone tel: Simon Walmsley tel: