Lightstreamer announces full JMX support for version 2.3

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News: Lightstreamer announces full JMX support for version 2.3

  1. Lightstreamer 2.3 has been released. Lightstreamer, the web push engine for live data distribution, has announced full JMX support as part of this new release. It streams real-time data to an HTML browser without the need to download or install anything on the client. It can also enliven any client application with streaming data, via API client libraries.

    JMX (Java Management eXtensions) is a widespread specification that provides a management architecture and API to allow any Java based technology or accessible resource to be inherently manageable. Lightstreamer 2.3 includes Sun’s JMX Reference Implementation and JMX Remote API. Due to this integration, the system administrator can now remotely monitor the quality of service of the Lightstreamer live data channels, together with the management of many other different aspects of the system. Any JMX-compliant management console can communicate with the JMX ‘agent’ included in Lightstreamer Server. A bridge for the MBean Server included in BEA WebLogic 8.1 is also available.

    Because Lightstreamer was developed in Java to provide a flexible and simple platform when adding live web based services to existing infrastructures, it was an obvious step to add JMX as a means to manage QoS. Subsequent to this release, under current development is the capability to push JMX data to a fully-fledged HTML management console, which will display details of Lightstreamer Server behaviour in real-time. In the next phase, a new Lightstreamer product is planned that will provide any JMX-compliant system with the capability to push JMX data in pure HTML.

    Visit the home page for: Lightstreamer.

    About Lightstreamer
    The Lightstreamer (Java based) technology was originally developed for the Italian Finance market by the Software Systems Integration activity of privately held Par-Tec group (founded in 1998). Weswit Srl was subsequently created as an Independent Software Vendor within the group to provide with Lightstreamer 'Push' middleware for streaming real-time Market Data, or in fact any live information to web browsers and custom application clients. Currently Lightstreamer is compatible with the following browsers: Microsoft Internet Explorer, Netscape Navigator, Mozilla, Firefox, Opera, Safari, Deepnet Explorer.

    Threaded Messages (15)

  2. Cool demo[ Go to top ]

    Very nice demos (upper right of the page).

    Anyone from the company care to go into a bit of the client side technology? Does it use a mechanism similar to gmail's xmlhttprequests? Or is this a different sort of "push"?
  3. The demos didn't work for me with Firefox 1.0. (They did work with IE6, tho.)

    Anyone else have any luck with Firefox?

    best,
    assmund
  4. Worked fine for me ...[ Go to top ]

    ... with Firefox 1.0.
  5. worked well[ Go to top ]

    I used Firefox 1.0. Worked pretty well, at least 3-4 of them.
  6. why cant download[ Go to top ]

    I read the whitepaper.
    seems like these guys know well what they talk about.
    Unfortunately they do not allow the download of application.
    They dont even publish javadocs. Come on!
    I need to see bits
  7. I hope I am wrong on this but if the columns on the stock ticker demo were allowed to be sortable, then the request would still have to go to the server (for sorting).

    Rich Internet Applications [RiA] (eg: Laszlo, Snapp etc) allow such functions to be done on the client (multiply this by 100,000 traders and the server gets stressed unduly).

    Its the streaming bit that makes this particular solution attractive, as no plugins are required either. However once RiA's catch up on this then the competition really hots up.

    All for the best no doubt.

    Cheers
    -raj subramani
  8. Full RIA achieved...[ Go to top ]

    The latest release of Lightstreamer engines now supports full client-side dynamic behavior, again without using Java applets or Flash components.
    Please have a look at Paged Portfolio Demo, where four client-side dynamic functions are shown:
    1) Rows are created and destroyed on the fly, without reloading the page neither to change the page structure.
    2) You can change the sort column and see the rows move without issuing any request to the server.
    3) If you sort by column such as “Time” (which provokes frequent position changes of the items), you will see that the items move between different pages at the appropriate time.
    4) If you switch to another page, the new page will be displayed without the need to make a request to the web server (in other words, the page switch is completely handled on the client side).

    Cheers
    Alessandro
  9. Interesting: as it is stated on features page:
    "True push (no polling, no refresh)"

    Ok, I am getting 'no refresh'. But does it mean that there is no polling at all?

    Dmitry
    http://www.servletsuite.com - web components
  10. It is realy true push.

    To better understand it see:

    http://www.javaworld.com/jw-03-2000/jw-03-pushlet.html

    Also an open source project by the author of this article:

    http://www.pushlets.com/

    And another project that is using the pushlets project:

    http://mis.sourceforge.net/

    Cheers

    Noam
  11. AFAIK, these "push" solutions require an open channel between the browser and the server. Can someone confirm this? If so, I would suspect scalability to be somewhat limited.
  12. streaming channel[ Go to top ]

    Yes, Lightstreamer Server keeps a permanent TCP connection for each client. On this streaming channel the updates travel, subjected to the adaptive filtering algorithms of LS, that detects network congetions and reduces the bandwidth when necessary.

    About scalability, Lightstreamer Server is based on Staged Event Driven Architecture, that permits very high loads to be handled. After continous optimization and refactoring, currently Lightstreamer can sustain 10,000 concurrent connections for each CPU on a Linux machine.
  13. In both cases (Lightstreamer and Pushlets) true push is used (not simulated push with hidden polling).

    The first group of differences is in the scope of the server. Lightstremer Server has been conceived as a push engine aimed to stream real-time data in the most efficient, optimized and reliable way (whether the client is an html browser or a full-fledged thick application), taking into account important aspects such as security, authorization, manageability, integration. So on the server-side the following exclusive features apply:

    1 – LS Server is implemented as a stand-alone process. It’s not a servlet or another kind of component running inside a web server or an app server. This approach was taken in order to have direct control over the operating system's TCP/IP stack. Instead of delegating the aggregation of data in packets to the operating system using the Nagle algorithm, Lightstreamer Server itself decides on each occasion the optimum composition of each TCP packet, with the objective/trade-off of reducing the delay time before data is sent off and at the same time minimizing the number of dispatched packets.

    2 – LS Server features Bandwidth Control. For each user, Lightstreamer can allocate a maximum bandwidth that is dedicated to the streaming channel. For example, if it is required that a certain user cannot exceed a bandwidth of 10 kbps, Lightstreamer will filter the data in such a way as to ensure that the streaming connection with that user always remains below 10 kbps. The system is also able to allocate a maximum update frequency for each user/item combination. For example, it is possible to configure the profile of a certain user so that they do not receive more than 2 updates per second for a certain subscribed item (piece of data). Filtering the data makes sense not only to limit the bandwidth occupied by the streaming connection, but also to improve the quality of data usage on the part of the end user. The “human interface” can absorb data by a combination of the human eye and brain, which are incapable of perceiving data changes of more than a few updates per second. Sending 30 updates a second would be a waste of bandwidth and computing resources, as they could never be taken in by a human user. However, Lightstreamer can also feed automated (as opposed to human) processes. In this case, it is possible to bypass the filtering mechanisms.
    Lightstreamer manages the filterable data feeds by means of a subscription mode called MERGE. However, there are data feeds that should not be filtered. Lightstreamer manages the non-filterable data feeds by means of a subscription mode called DISTINCT. Lightstreamer also offers another three methods of subscribing push data: RAW, COMMAND (that makes it possible to handle the so-called meta-push) and COMMAND-MATCH.
    The advantages of bandwidth control are obvious, both for the server and for the client. For the server, bandwidth control makes it possible to size the Internet connection required simply and accurately. For the client, bandwidth control makes it possible to avoid saturating the bandwidth of the user's modem. Traditional push connections through narrow band equipment (e.g. analog modems or GSM/GPRS mobile networks) risk rapidly saturating the available bandwidth and blocking the user's access to other services. With Lightstreamer, 4 Kbps can be allocated to the push channel on a old GSM mobile phone, leaving about another 5 Kbps free to access other Internet services. In other words, bandwidth control allows partitioning of the client's bandwidth among various applications.

    3 – LS Server features Adaptive Streaming. The ability to allocate a maximum bandwidth to each user may not be sufficient to ensure that the push connection is managed in the best way possible, cause of Internet congestions. The system has to be able to take into account exactly how much bandwidth is actually available at any moment in time. Lightstreamer automatically spots situations of congestion on the Internet, heuristically slowing down or suspending the dispatch of data until the connection is again fully serviceable. This means that if at any time the actual available bandwidth is less than the allocated and required bandwidth, Lightstreamer uses its own filtering mechanisms to modulate the transmission of data with a more suitable bandwidth. The advantage of this is that when the channel becomes available again, the user does not receive a burst of obsolete updates, but immediately starts to see the new data (in other words, data aging is avoided).
    Adaptive streaming is particularly useful for connections that are notoriously unstable and variable, such as those on mobile networks. Let's assume that the user starts a push session on their GPRS smartphone (using one of the many mobile clients made for Lightstreamer). If at a certain point the GPRS signal deteriorates and the effective bandwidth narrows Lightstreamer Server detects what is happening and adapts the streaming in a dynamic way to the new network conditions, even going so far as to suspend the transmission of data in the event that no bandwidth is available at all.

    4 – LS Server features very high performance. Instead of using one thread for each concurrent user, it is based on a staged event-driven architecture, that together with Java NIO libraries adoption, is able to handle very high low. The benchmarks have shown that many thousands of concurrent streaming connections can be sustained by each CPU of the server. Furthermore LS Server can scale very well, both by adding more CPUs in each box and by adding low-cost single-CPU boxes to the cluster. When the data feed produces very high-frequency updates, a multi-stage filtering algorithm is available in Lightstreamer Kernel.

    5 – LS Server features a complete system for handling security, authentication, authorization. When a client (be it an HTML client or of any other nature) connects to LS Server, it sends its credentials, that are validated by LS Server against any back-end system through its Metadata Adapter. Then, each subscription request (with single-item granularity) must be authorized by the Metadata Adapter before it is honored by LS Server. The streaming channel can be based both on HTTP and HTTPS.

    6 – LS Server is fully compliant with JMX (Java Management Extensions) specification. The server can be monitored and administered through any JMX-compliant console. Furthermore, a built-in Web console is provided that shows many indicators about LS Server in real-time (using LS itself to push the updates).

    7 – LS Server can be integrated with any kind of data source and authentication system through an expandable and flexible system based on Adapters. Open Java API’s are provided to develop Data Adapters and Metadata Adapters. Each Lightstreamer Server instance can handle multiple Adapters.


    About client-side technology, more differences with Pushlets arise:

    1 – The HTML clients are only one family, though appealing, of the possible clients of Lightstreamer Server. A Java Client Library is provided to write thick Java clients. A DDE Gateway is also available to push the updates to Excel spreadsheets and other Windows applications. But in the next paragraphs we will focus on the Web client, to allow a comparison with Pushlets.

    2 – Lightstreamer is focused on keeping the JavaScript libraries compliant with the broadest range of browsers. Current compatibility comprises: Internet Explorer, Mozilla, Firefox, Netscape, Opera, Safari, Deepnet Explorer, Philips iTV. We will introduce very soon backward compatibility with old generation browsers like IE 4 and glorious Netscape 4. But the new frontier is the compatibility with micro-browsers (Pocket IE, Opera for Mobile, Minimo, NetFront, etc.). The current version of Lightstreamer web front-end is already compliant with Opera 7 for mobile phones (that is adopted on Motorola A1000).

    3 – Any existing Web front-end can be transformed into a Lightstreamer-compliant one by following some simple guidelines, whatever is the technology employed to produce the pages (JSP, PHP, ASP, etc.). The static part of the pages, the layout, the images and other resources keep on being hosted on the original Web server.

    4 – Lightstreamer Web Client handles fail-over. If the Lightstreamer Server instance to which it is connected breaks down, it automatically reconnects to another instance and recovers the session, without the user doing anything.

    5 – Lightstreamer Web Client never saturates the memory of the browser (a perpetual buffering of events would be lethal).

    6 – Lightstreamer Web Client is able to update simultaneously the content of various frames and pop-up windows with only one single multiplexed HTTP connection. This way the browser’s connection pool never gets saturated,

    7 – Lightstreamer Web Client permits the dynamic subscription and unsubscription of pushed items through control connections that don’t impact on the permanent stream connection.


    For further details a White Paper is available at http://www.lightstreamer.com/download.htm.
  14. XMLHTTP[ Go to top ]

    Good work! But it not free... ;-(

     I think XmlHttp can do this property. But it can work only in IE6.
  15. must be expensive[ Go to top ]

    They have no pricing on the web site.
  16. It works well on Firefox1.0. Btw very nice demo.

    Thanks,
    Surapong K.
    Mfatix Company Limited
    http://www.mfatix.com