Types Of Push Technology

Published Date: 02 Nov 2017

Introduction:

Push technology is a mobile specific technology and its concept is introduced by the HTM5. In this technology information is being transmitted from the server to the client sides, clients are computers or could be mobile phones. And in PUSH technology event based data is being transmitted to the client like if any email any news update any weather forecast etc. Push technology(http://docs.database.com) is a model of Internet-based communication in which information transfer is initiated from a server to the client. Also called the publish/subscribe model, this type of communication is the opposite of pull technology in which a request for information is made from a client to the server. The information that’s sent by the server is typically specified in advance. When using Streaming API, it is specified the information the client receives by creating a PushTopic. The client then subscribes to the PushTopic channel to be notified of events that match the PushTopic criteria.

Types of PUSH technology

There are different types of PUSH-technologies working in the marketplace but more likely SMS PUSH-technology, WAP PUSH-technology, Server-TCP/IP PUSH-technology, HTML PUSH-technology and Vendor Specific PUSH-technologies are described as following.

SMS PUSH-technology: SMS PUSH-technology is the simple technology in which sms are being sent as any update or alert against the event. It is also known as WAP PUSH . An sms is sent to notify the client to the availability of the required data hence causing an additional cost to send that sms.

Server TCP/IP PUSH: This technology is designed for the 3G devices when users or devices are having public ip address and are easily available and accessible for the server to make a connection and send the relative data and contents upon alert or any event. So this process is likely to be good for the networks where remote clients are not using NAT.

Client TCP/IP PUSH: In this PUSH technology the restrictions made by the Server TCP/IP technology are tried to be removed. In the method client establishing a connection to the desired server and doesn't kill it and whenever there any update or event server simply passes all the relative data and contents to the user/mobile device through that already made and opened connection. There is another variation of this that is called Scheduled Polling in which client stays connected only a limited period of time by giving the server a better scalability as only a specific numbers of users will be connected any any given time. So the server would be easily define the higher amount of clients without any problem.

WAP PUSH: WAP PUSH-technology is used to deliver data contents to the users with synchronizing or establishing a preplanned connection to the user. WAP contents are targeted for the desired users and they have them remotely. In the WAP PUSH-technology contents are delivered to the users without previous interaction. A PUSH initiator is responsible to PUSH the contents to the PUSH Proxy Gateways that delivers the contents to the WAP clients according to the defined instructions. The PUSH initiator is an application running on a web-server communicating with the Mobile Access Gateways using PAP (PUSH Access Protocol).

HTML PUSH: HTML PUSH-technology also called http data steaming is to send data from a web-server to the web browser. In this technology connection is remained established so that if there is anymore updated content, it should be sent to the targeted client immediately. Otherwise if the connection is terminated after the first page then server has to wait for the queue of requests being sent from the users point. HTM5 is favorite tool that is being used to implement HTM PUSH-technology.

Implementation of PUSH technology

PUSH require client end and server end software to cooperate with each other to fulfill the users requirements. Usually the end user has the mechanism that how to work with PUSH technology. All the requesting, Following is an example of the components of Blackberry PUSH application service.

A PUSH application (us.blackberry.com ) service is comprised of three components.

The server side PUSH service that is used to develop PUSH service in turns offer users consumable data . So whenever data or updates are available, content providers can submit PUSH request to deliver the available data.

A client-side application make use of data being offered by the associated PUSH service. The client service initiate a listener in the background to carpture the incoming data from the server.

(III)The blackberry infrastructure work as middle ware receiving requests to PUSH data from the content provider and then that data is being delivered to the specific application to which that data is associated.

(us.blackberry.com/ )

In the above figure (Process Flow),a blackberry PUSH technology process has been explained in which it can be seen how a blackberry PUSH technology works.

In this example (1) the content provider sends a PUSH request to the Blackberry PUSH data servers

in this request user (mobile client) has already subscribed the required services and against it Blackberry PUSH data servers (2) returns a reply to the mobile client via the content provider along with the mobile client sending a receipt of request and queues the request for delivery of data (3) then thee blackberry PUSH data servers send that subscribed data to the mobile client (5) Finally, each black berry (mobile client) device returns a response to the blackberry data servers that in turns sends a response to the Content PUSH initiators.

PUSH content providers and Data servers keep updating the user by using different techniques ie. Long polling , short polling and streaming etc. With the traditional sort polling a mobile user or client regularly keep sending the requests to the server to pull any updated event or data. If there is no update the data sever replies with an empty response but if there is any update or event , clients get it otherwise it waits for new updates and events. By contrast with such "short polling", "long polling" attempts to minimize both latency in server-client message delivery and the use of processing/network resources (http://tools.ietf.org) while in long polling the mobile users wait for a response after making a request there no response not even the empty response till a new update or event arises. After the data server has a complete update of response it sends it to the client. After the the mobile users sends another long poll request immediately upon receiving an updated data. But the Long polling has Header Overhead in which a complete http message will be sent to thee mobile user. After a long polling request has been made by the client and servers sends the required data a long polling request must be made to the data servers and data servers waits for that long polling requests from the clients. Another common drawback in long and short polling requests is that these request frequently establishes an Http tcp/ip connections and close them. Another drawback is the allocation of resources in which OS will allocate resources to these connections and requests based on these connections. In the long polling client or server both that are being loaded by these polling requests has a low performance because of message latency. Also the timeout issues are there because of long polling request has to wait for a long time for any new updates or events

Benefits of PUSH Technology

There are two immediate(http://jungleg.com/) benefits of PUSH technology first one is that if somebody urgently waiting for an email and other person is waiting for its update so when the receiver will access it then other person could be updated about that. PUSH technology save the bottlenecks of network traffic by automatically updating the user regarding any event. Mostly well known and widely used now-a-days PUSH technology was Microsoft Exchange when a popup informs about the new arrival of an email on computer’s Outlook.

In the above example of Blackberry implementation of PUSH-technology it is clearly seen the following benefits can be achieved .

Pushing data to the Blackberry devices is much more efficient. With it developers can easily send data to Java applications. It also minimizes the network latency as wireless networks are less faster than the wired networks so Blackberry PUSH APIs works in the background without the users involvement,users or mobile devices has to just receive the subscribed data. So users feel that there is no wait time.

The applications developed using Blackberry APIs reduces the long poll drawbacks as well that is there is no need to continuously poll the servers. Blackberry PUSH-technology APIs are designed to handle large amount of data. Battery life issue is very very important for mobile devices so developers are really trying always to develop such applications that consume very less battery. It is always in consideration that host device has enough battery to operate that application. Some applications need to repeatedly poll the data server to retrieve the required subscribed data. The mechanisms used in Blackberry APIs is that instead of actively polling the data the developed application actively listens to the data in the background without letting the users know about that hence feeling the users that no waiting time is there. So, once data is delivered to the users again the application can start actively listen and also start processing the accessed data.

Blackberry PUSH-technology APIs also reduces complexity for the the developers that uses by handling all the push requests analogy. By doing so all the complexity of the PUSH requests is hidden from the developers. In the PUSH-technology as users are too much engaged so it can also help in generating revenues by means of transactions, advertising and subscriptions.

Alternatives to PUSH Technology

Opposite to the PUSH technology is PULL technology in which client requests the data from the server and data is being transmitted from the server side to the client side. In the following figure alternative to the PUSH-technology has been illustrated and it is traditional mechanism of accessing the web and all those documents that is simply accessed by the Computer’s user. This traditional mechanism is now customized if not using the PUSH-technology to help give the benefits PUSH-technology. The data over the internet whether it is designed for the PUSH-technology or for simply PULL mechanism may contain rich texts format, audio/video files, many graphics. Similarly, along with those pages other HTTP links can cause the user to retrieve automatically the data and contents related to it. For the computer users it not an issue to do so whether by means of PUSH-technology or simply PULL mechanism as there is enough bandwidth and resources available to use that.

www.library.ca.gov/

In the Figure-1 is the alternative to the PUSH technology that has been widely used and still being used in which user always makes request to the server and server is sending pages or response on the basis of those requests to the user for its requirements. In the mechanism every times a new requests comes in the page is being sent to the user against its request.

www.library.ca.gov

Here in the figure-2 PUSH-technology has been elaborated vs Pull technology. All the users are subscribing to the required data . And the Content data provider is giving them the required data by processing in the background. In the figure-2 selected channels are presenting an example of the users selected or subscribed services that are being PUSHed towards the user with special mechanism without the users letting know about that.

Conclusion

In PUSH-technology services and content providers are at one end and for so many users they are using NAT and HTTP proxies. This thing is currently limiting the use of PUSH-technology so widely and that is why its expensive as well. But with the latest development of IPV6 it will become easier without NATing and Proxies to use the PUSH-technology services. Using Open Sources, PUSH-technology introduces enhancement in the usability and security of data transmission, control of data content and user interaction. All these capabilities will allow increment in using and adoption of the mobile internet. It also provides many opportunities to the content developers to create more new, secure, interactive and innovative applications.