PPC+Copy

=Term 3 - w1. Please go here, read the instructions and work through.= = = =Contents= = **__Convergence__** = = __**Teleconferencing and Videoconferencing**__ = = __**VoIP**__ = = __**Web Seminars**__ = = __**Smartphones**__ = =Push Pull Technologies= = __**Intercepting **Communications****__ =

= = = __**Technological Convergence**__ =

Traditionally, ** communications ** media were separate and their services were distinct. Broadcasting, voice telephony and on-line computer services were different and operated on different platforms: TV and radio sets, telephones and computer. Each of these was regulated differently by different regulators. Convergence is the combination of all these different media into one operating platform. It is the merger of telecom, data processing and imaging technologies. This convergence is ushering in a new epoch of multimedia, in which voice, data and images are combined to render services to the users. Traditional convergence is noted in the combination of the ** personal ** computer and the internet technology. This combination provides a convergence of data processing, images and audio services. Recent examples of new, convergent services include:
 * Internet services delivered to TV sets via systems like Web TV;
 * E-mail and World Wide Web access via digital TV decoders and mobile phones;
 * Web casting of radio and TV programming on the Internet;
 * Using the Internet for voice telephony

Technological convergence points to the way technologies are increasingly converging into one. The availability of carrier technology with high bandwidth means that, transmission is not limited to voice only, now data, picture and other multimedia and interactive media can be transported in one single carrier technology like the fibre optic cable and satellite technology. One other noticeable technology that perhaps is the epitome of convergence technology is the Computer technology. This technology provides the most striking convergent service: Internet. The Internet combines all know communication media into one single service on a computer screen.

 = __**Teleconferencing and Videoconferencing - beware of the terms!**__ =

When describing **video conferencing** systems, there is a common interchanging of words that mean the same thing. **Video conferencing** is the same as **video teleconferencing**. The phrases are both used to describe __a meeting between parties in different locations wherein the meeting participants use ** communications ** equipment to both see and hear one another as they interact.__

There is similar usage for phrases associated with **teleconferencing**. __Teleconferences are called both audio conferences and teleconferences__. In each, three or more telephone callers are linked together in a telephone call with all parties hearing one another and some or all parties interactively speaking.

Therefore, **teleconferencing is a blanket term** __used to describe, overall, communication between two people at remote sites, via video and/or audio. This also includes the term "video conferencing", "voice over IP", etc.__

[|How teleconferencing works?] [|All about teleconferencing] [|Advantages and Disadvantages of Teleconferencing]

Alistair's Notes: Teleconferencing.docx

Jeremy's Notes: Teleconferencing and Videoconferencing.docx  = __**VoIP**__ = [|How VoIP works video] [|How VoIP works] 7 Things Skype.pdf

 = __**Web Seminars / Webinars**__ = [|How Web Seminars work] [|Advantages and Disadvantages of Web Conferencing] [|Disadvantages of Web meetings]

Alistair's Notes: Webinars.docx  = __**Smartphones**__ =

**What Is a Mobile Phone?** A mobile phone is more frequently called a cellular phone or cellphone. These communication devices connect to a wireless ** communications ** network through radio waves or satellite transmissions. Most mobile phones provide voice ** communications **, Short Message Service (SMS), Multimedia Message Service (MMS), and newer phones may also provide Internet services such as Web browsing, instant messaging capabilities and e-mail.

**What Is a PDA?** Short for //**** p ****** ersonal ** **d**igital **a**ssistant//, this is the name given to small handheld devices that combine computing, telephone/fax, Internet and networking features. A typical PDA can function as a cellular phone, fax sender, Web browser and ** personal ** organizer. These devices are usually pen-based, which requires the use of a stylus rather than a keyboard for input. PDAs today are available in either a stylus or keyboard version. Traditionally, PDAs have not had phone or fax services.

**What Is a Smartphone?** A smartphone is considered to be the combination of the traditional PDA and cellular phone, with a bigger focus on the cellular phone part. These handheld devices integrates mobile phone capabilities with the more common features of a handheld computer or PDA. Smartphones allow users to store information, e-mail, install programs, along with using a mobile phone in one device. A smartphone's features is usually more oriented towards mobile phone options than the PDA-like features. There is no industry standard for what defines a smartphone, so any mobile device that has more than basic cellphone capabilities can actually be filed under the smartphone category of devices.
 * Smartphone basics**

[|Smartphones & PDAs]: [|Smartphone Basics]

[|How Smartphones Work - How Stuff Works]


 * Smart Phones are an excellent example of technological convergence. David Pogue, a journalist from the NY Times, provides some excellent examples of this on new Smart Phone technology.**

[|Smartphones or hand held computers?] [|Smartphones - the pro's and the con's] The advantages of using a smartphone include: The disadvantages of using a smartphone include:
 * live (online) access to data
 * reduces the number of devices a doctor needs to carry
 * much better web browsing capability than a cellphone
 * integration of contact / phonebook databases
 * requires an expensive wireless data plan
 * a single device means a single point of failure
 * policies restricting cellphone use at many hospitals
 * bigger and heavier than a regular digital cellphone
 * hard to use your PDA at the same time as talking on the phone

[|Mobile workers push for smartphones] [|The benefits of smartphones]


 * The effect of mobile phone devices on human behaviour - have we really become anti-social?**

[|Shock tactics for anti-social mobile phone users] [|Mobiles 'let you control your life'] [|Beware what you share. We know where Adam Savage lives.]

__**Mobile Phone Addiction**__ [|Mobile phones becoming a major addiction] [|Are kids becoming phone addicts?] [|Technological stimulus affecting our ability to concentrate]

__**Mobile Phones and Health**__ [|Effects of wirless **communications** on our health] [|Mobile Phones and Health Effects]  = __**Push Pull Technologies**__ =


 * Interestingly, comes first with ** communications ** technologies?**




 * __//Of pulls and push//:__**

=
Traditional Web browsing has been based on the model of '//pull//' - wherein, when a user requires information he visits the website thereby making a request and the browser '//Pulls//' or downloads the information into his computer. =====

=
A new form of information delivery called '//push//' is rapidly gaining popularity. '//Push//', in fact, amounts to //pull// and //push//, //pull// out relevant information from a large number of sites and //push// into computers of individual clients. The information can be made available to viewers just like television broadcast media except that the viewer 'subscribes' to his channels of interest. Information is then sent regularly to his system. =====

=
The technology uses client-server software of varying degrees of sophistication. The **advantages** are several : =====  Surfers find it quite annoying to reach for the 'reload' button every time transfer is interrupted. Web pages with dynamic content is another reason to refresh pages at the client end. //push-pull// technology seeks to solve this problem by periodically downloading pages to the client. There are two ways of doing this : "C//lient-pull and Server-push".// With //client-pull//, the change is instigated from the Web client end. After a certain period, (usually defined within the Web page), the browser requests a page again, during which time elements on it may have changed, causing the displayed Web page to evolve. Included with the data is a directive that might say, 'reload this data in 10 seconds,' or ' go load this other URL in 20 seconds.' After the specified amount of time has elapsed, the client does what it was told to do in the directive (reloads or goes to another URL.). The browser automatically displays the reloaded data or new URL. Alternatively, //server-push// can be used. In this, it is the server that determines when things change, and simply sends down the new data. This method can be more efficient, since new HTTP connections don't have to be opened all the time. The downside is that the open connection consumes a resoruce on the server side while it's open (only when the server knows it wants this to happen, though). Although at first glance these might seem very similar, there is a fundamental difference. With //client-pull//, the connection is closed after each transfer in the normal way. The client is told when to open a new connection, and what data to fetch when it does so. But with //server-push//, the connection is left open so that the server, whenever it wants, can send more data for the client's browser to display. The process continues to repeat itself with the connection remaining open and the server sending new information periodically. Now the __client is able to surf the internet from the local disk__.
 * =====It cuts down on browsing time, particularly for those who have low - speed connections. =====
 * =====It enables a client to know when updates have been made to their favorite sites, because notices of these are sent out via e-mail. =====
 * =====Channels offered by '//push//' developers could be seperate ones for news, weather, sports, softwares and so on, so it lets you select channels that deliver **//focused content//**.Focused content here means, the user is given //hyperlinks// only to selected news. =====
 * =====**//Advertisers & Internet Programmers listen !!!//** Server can authoritatively //push// advertisements and make sure that Client has to view all those advertisements while receiving genuine information in background from Server. This can be achieved either by displaying those advertisements in Client's window, or by inserting the same in //pushed// information. =====
 * =====The big **disadvantage** is that the more //push// players there are, the more it increases Net traffic. //push// companies send out crawlers to check websites for updates, and these can be a factor for **congestion** on the net. =====
 * __//The mechanics of push-pull// :__**
 * How it works?**

 = = = __**Intercepting ** Communications ****__ =

__**Wiretapping**__ [|How wiretapping works] [|Wiretapping] [|Wiretapping, whistleblowing and IT ethics] See also Intercepting ** Communications **, Chapter 3.2, A Gift of Fire (p.98-109 in the 2003 edition)

__**Packet Sniffing**__ [|Packet Sniffing] [|Techstuff Podcast - Is your ISP sniffing packets?]