information about the al l--->
salient features of e-mail,URL.,contrast,google, yahoo ,Telnet Session,FTP


1. Explain the salient features of e-mail? Explain its working with the help of an example.

Soln: - Electronic mail, or e-mail (and mail) for short, is one of the most popular uses of the Internet. Once you have an e-mail account you can send an electronic message (sort of like a letter) to just about anyone else with an e-mail account so long as you know their e-mail address. The salient features of e-mail are: -
• Delay message sending and offline mail reading
• Multiple e-mail account checking
• Automatic mail forwarding and mail checking
• Mail filters and automated mail processing
• File attachment and flexible formats
E-mail is not a live connection between the sender and its recipients. There is always a delay between the time a message is sent and time it arrives. Because e-mail work as a store forward system. Our e-mail system consists of two different server or protocol running either on the same machine or different machine. Theses two servers are SMTP and POP. SMTP stands for simple mail transfer protocol. It is used for handling outgoing mail. The POP stands for Post Office Protocol. It is used for handling incoming mail.

2. Most people these days subscribe to a newsgroup? What do you understand by a newsgroup and how can you subscribe to it?
Soln: - Usenet newsgroups are Internet discussion groups on just about any topic you can imagine. There are more than 50,000 newsgroups, and more are added all the time. The first way students and scientists using ARPANet (early version of the Internet) started sharing their interests and hobbies was to create newsgroups. In newsgroups students and scientists placed information about their interets and as the number of newsgroups began to expand, the Internet administrators grouped all newsgroups together to form a category known as Usenet. A newsgroup is a kind of open discussion group devoted to a selected topic. The internet is host to thousands of newsgroups, with a wide range of topics. Unlike email when you post to a newsgroup anyone is able to see your message. Although this may not sound appealing, there are many advantages to using newsgroups, one of which is the ability to help each other. For instance if you where to subscribe to an Operating System newsgroup, you may have encountered and fixed a problem someone else may be having. You can then share your knowledge on this topic, not just to assist this person but anyone else who may be reading your message with the same problem.
3. Compare and contrast between FTP and Telnet. How a Telnet session can be established?
Soln: - FTP (stands for File Transfer Protocol) is a communication protocol between two computers for the purpose of transferring files back and forth (uploading / downloading), deleting files.
Telnet gives you command line access to a remote computer. While you can transfer files via telnet, its main differences is you can execute commands (simple ones such as dir, cd and the like) to more advanced things like starting/restarting services. Telnet is a method of remotely accessing a server. It is accomplished via the use of a Telnet client which actually emulates the servers program on your own computer. You can use Telnet to make/remove directories; create, rename, remove files; change modes; get information from the server; manipulate files; etc.
Established a Telnet Session: - You can establish another Telnet session while you are in a current Telnet session. After you establish a cascaded session, you can move between the different systems. The home system is the first client system that you use. The end system is the last Telnet server system that you access. The system that you pass through to get from the home system to the end system is an intermediate system. After you start a Telnet session, press Enter to display the System Request menu. There is no limit the number of systems to which you can establish a Telnet session. To start Telnet session, sign on to the home system, then establish a client session. To establish a connection to a telnet server, create a Telnet instance and provide the required hostname.
4. Search engines like google, yahoo etc. are widely used these days.What is the purpose of using it? How do they help users in using Internet?
Soln: - Search is rarely absolute. Search engines use a variety of techniques to imitate how people think and to approximate their behavior. As a result, most rules have exceptions. With a search engine, keywords related to a topic are typed into a search "box." The search engine scans its database and returns a file with links to websites containing the word or words specified. Because these databases are very large, search engines often return thousands of results. Without search strategies or techniques, finding what you need. To use search engines effectively, it is essential to apply techniques that narrow results and push the most relevant pages to the top of the results list. There are many search engines and directories available on internet such as Google, Yahoo, MSN, AltaVista, AOL etc. But Google is considered as one of the major and popular search engine in the world. Because of efficient and quick search results availability, Google is going to be more and more popular in the world for finding information. Google is very popular not only for searching information but for various other product facility offered by Google. When internet users search for any particular information and type some search query, they find list of pages with website name, title and short description about the website. It shows 10 website’s details on each page. It is possible that there are more than millions of websites available for your particular search. Your website can also belong to that millions of web sites
5. Compare and contrast between a network and Internet.
Soln: - The difference between the two is that internet is the world wide web and network is local. Actually internet is one of the part of computer networks.There are three types of computer networks LAN(Local Area Network)where you can communicate only within some desired distance,MAN(Metropolitan Area Network)where you can communicate within a city,&WAN(Wide Area Network)where you can communicate within the entire world.Internet belongs to the third type.We can also say that Internet is one of the applications of computer networks.
6. Explain the typical structure of a URL.
Soln: - Uniform Resource Locator (URL) is a subset of the Uniform Resource Identifier (URI) that specifies where an identified resource is available and the mechanism for retrieving it. The Uniform Resource Locator was created in 1994 by Tim Berners-Lee as part of the URI. The first part of the address is called a protocol identifier and it indicates what protocol to use and the second part is called a resource name and it specifies the IP address or the domain name where the resource is located. Uniform Resource Locator is also defined as the global address of documents and other resources on the World Wide Web.