1. What Is Real-Time Communication?

INTERNET AND JAVA

Unit-2

2 Marks

1.  What is real-time communication?

In some types of chatting and conferencing, messages are sent immediately after they are complete (for example, as soon as you press ENTER after typing a message). This type of communication is called real-time communication.

2.  What is an asynchronous chat?

Allows participants to consider their responses, gather information, and formulate a response carefully. It also allows people from different time zones or with different schedules to participate. For example, there may not be a time when all the members of a committee are available for a real-time meeting.

3.  What is a Usenet, newsgroup and newsreader?

Usenet is a system that allows messages to be distributed throughout the Internet. Because of the volume of messages, the messages are divided into newsgroups, or topics. You use a newsreader program to subscribe to a newsgroup, read the messages posted to that newsgroup, and post your own messages.

4.  What is an IRC?

Internet Relay Chat (IRC) allows thousands of Internet users to participate in real-time text-based chat. When you use an IRC program to connect to a central IRC server and join a conversation (called a channel), you see all the messages that are typed in that channel within seconds of when the messages are sent. The IRC program enables you to type and send your own messages, too.

5.  What are MUDs and MOOs?

Multiuser dimensions (MUDs) are text-based chats in which the participants play a game by following a set of rules enforced by the central server computer. The game is usually a fantasy game, but may be an online university or other group event. MUDs object oriented (MOOs) are user-programmable games that are similar to MUDs: by programming, participants can create objects in the shared world of the MOO.

6.  What are the types of Mailing Lists?

·  Open vs. closed subscriptions

·  Open vs. closed posting

·  Moderated

·  Digests

·  Archived

·  Reply-to-list vs. reply-to-sender

7.  What is MLM?

The mailing list management program responds to all messages addressed to both the list address and the list’s administrative address. Messages to the list address are distributed to the subscribers. Messages to the administrative address are processed by the program: for example, a message with the command subscribe might add the sender to the subscriber list. Subscribers communicate with the MLM entirely by sending commands to the administrative address for the list.

8.  What are the commands used to read the archives of a list?

To read the archives of a list, you use two commands:

·  Index To see a list of the archive files

·  Get To request an archive file

9.  What are the basic newsgroup hierarchies available?

The following are the original seven hierarchies and their respective topics:

·  comp Computer hardware, software, networking, and other computer-related topics

·  misc Miscellaneous topics

·  news Usenet itself

·  rec Recreational topics

·  sci Scientific topics

·  soc Social topics

·  talk General discussion

10.  What is NNTP?

News servers and newsreaders communicate by using an Internet protocol called the Network News Transfer Protocol (NNTP).

11.  What do you mean by spam?

Spam is a nickname for unsolicited commercial e-mail, but the term is used for Usenet postings, too.

12.  What is an IRC network?

IRC networks (or nets) are the backbone of IRC. IRC networks are groups of IRC servers that are linked together over the Internet, enabling chat sessions to span the globe. All the public IRC networks are accessible via the Internet.

13.  What is an IRC Server?

IRC servers are computers and software that work like IRC switchboards, letting users connect to them by using an IRC client program. Most IRC servers are at universities or ISPs. IRC server computers run the programs that enable you to connect to an IRC net, keep track of users and channels, and make sure that all the messages that all the users type get to the right place

14.  When does a netsplit occur?

A netsplit occurs when one or more servers split off from the rest of the net, due to a communications problem. Usually, a netsplit is caused by an overload of users. The servers that split from the rest of the net (and all of their users) are still able to communicate with each other, but not with the rest of the net.

15.  What is a lag?

Lags sometimes are associated with netsplits. The lag is the time that it takes for your message to travel from your server to the net. Before a netsplit, the lag is frequently long, which is an indication that the servers are overloaded and experiencing problems. Sometimes, a lag affects only one or two servers, and sometimes it affects many servers.

16.  What is a DCC?

The Direct Client to Client (DCC) protocol enables you to send files or chat with other users by establishing a direct connection between your computer and theirs. This connection bypasses the IRC server and connects you directly from your ISP to the other person’s ISP.

17.  What do you mean by web server and web browser?

A Web server is a computer connected to the Internet that runs a program that takes responsibility for storing, retrieving, and distributing some of the Web’s files. A Web client or Web browser is a computer that requests files from the Web.

18.  Give the difference between a Web page and a Web site.

A Web page is an HTML document that is stored on a Web server and that has a URL so that it can be accessed via the Web.

A Web site is a collection of Web pages belonging to a particular person or organization.

19.  What is a portal?

A portal is a Web site that wants to be your start page, the page that your browser displays first. That is, the portal wants to be the place where you start your browsing experience—and see every time that you turn on your Web browser.

20.  What are plug-ins?

Plug-ins are programs that are independent of your Web browser, but that “plug in” to it in a seamless way, so that you may not even be aware that you are using a different piece of software. Various plug-ins (such as RealAudio for receiving streaming audio, or QuickTime for downloading video) have become standard accessories for IE or Navigator, and are installed automatically when you install the Web browser.

21.  What is a Cookie?

A cookie is a small (at most 4K) file that a Web server can store on your machine. Its purpose is to allow a Web server to personalize a Web page, depending on whether you have been to that Web site before, and what you may have told it during previous sessions.

22.  What are the major risks involved in any Internet transaction?

·  Eavesdropping Any information that you transmit may be overheard by other computers—your credit card number, for example.

·  Manipulation The information that you send or receive may be altered by third parties. For example, the delivery address for your shipment might be altered.

·  Impersonation You might not be dealing with the entity that you think you are dealing with. Or, conversely, whoever you are dealing with might gather enough information to impersonate you in another transaction.

23.  What is PICS?

The Platform for Internet Content Selection (PICS) is an Internet protocol that enables ratings to be transferred and understood across the Internet. PICS is a technique for associating an HTML document with a label containing information about its content. A Web browser reads the label first, compares it to criteria set by the user, and then decides whether to display the page.

24.  How do web-based search engines work?

A Web search engine employs a search agent (also called a spider) that goes out and looks for information on Web pages. This information is indexed and stored in a huge database. When you conduct a search, the search engine looks through its database to find entries that match the information you entered. Then, the search engine presents to you a list of the Web pages that it determines are most relevant to your search criteria.

25.  What are Web Directories?

A Web directory is a Web site that categorizes Web pages, so that you can browse links to Web pages by topic. For example, the Yahoo! Web directory includes categories for Arts and Humanities, Business and Economy, Computers and Internet, Education, and a dozen others.

16 Marks

1.  Explain in detail how to propose a new newsgroup.

·  Creating a Mainstream Newsgroup

o  Explain the groups involved

o  Give the general steps to be followed

·  Creating an Alt Newsgroup

2.  Explain the common newsreading Tasks.

·  Configuring Your Newsreader

·  Subscribing to Newsgroups

·  Selecting and Reading Articles

·  Posting Messages

3.  How does Chat work? What are the Chat Etiquette available?

·  Identifying Yourself

·  Topics, Newsgroups, Channels, and Rooms

·  Following the Discussion

·  Mention the various Chat Etiquette which comes around 15 points

4.  Explain Subscribing and Signing Off a mailing list.

·  Sending a Subscribe Command

·  Tips for Sending Commands

·  Confirming Your Subscription

·  Solving Subscription Problems

·  Signing Off Mailing Lists

5.  Explain chatting in mIRC in detail

·  Getting mIRC

·  Connecting to an IRC Server

·  Listing Channels

·  Joining Channels

·  Starting to Chat

·  Whispering

·  Sending Files

·  Leaving Channels and Disconnecting from Servers

·  mIRC Tips

6.  Explain the Security and privacy issues in WWW.

·  Cookies

·  Firewalls

·  Secure Communications and Transactions

o  How Secure Transactions Work

·  Executable Applets and Scripts

·  Viruses

·  Privacy Implications of Browser Caches and History