An intranet refers to a private network within an organization that connects computers and offices using non-public network links, with firewall protection. An extranet extends an organization's intranet to external users via the public internet. A leased line is a private telecommunications connection between two locations that a provider delivers for a monthly fee. SMTP and POP are protocols for sending and retrieving email over the internet. HTML uses tags for markup while XML requires complete tagging and is more structured.

1. Difference Between Intranet and Extranet Intranet refers to a collection of networks within a logical body, such as a building, corporation or other entity. Intranet can be as simple as two computers connected at home to each other, or as vast as 1000 branch offices of a bank, connected via privately owned, non-public network links. Intranets usually have a firewall and router, which permits access to the public Internet, while protecting the internal Intranet from malicious users

2. Intranet vs. Extranet

3. An extranet is a private network that uses Internet protocols , network connectivity. An extranet can be viewed as part of a company's intranet that is extended to users outside the company, usually via the Internet . It has also been described as a "state of mind" in which the Internet is perceived as a way to do business with a selected set of other companies ( business-to-business , B2B), in isolation from all other Internet users. In contrast, business-to-consumer (B2C) models involve known servers of one or more companies, communicating with previously unknown consumer users.

4. Difference Public, Private Networks and Leased Line public network- consists of two services. It is important to understand the concept of switched and dedicated services since mistakes in configuring telephone networks could result in extra expense, insufficient capacity and increased maintenance. private network- is a network that uses private IP address space, following the standards set by RFC 1918 and RFC 4193 . These addresses are commonly used for home, office, and enterprise local area networks (LANs), when globally routable addresses are not mandatory, or are not available for the intended network applications. Private IP address spaces were originally defined in an effort to delay IPv4 address exhaustion , but they are also a feature of the next generation Internet Protocol , IPv6 . A leased line is a service contract between a provider and a customer, whereby the provider agrees to deliver a symmetric telecommunications line connecting two locations in exchange for a monthly rent (hence the term lease).

5. Lease Line Network

6. Private Network

7. Public Network

8. SMPT VS. POP Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission across Internet Protocol (IP) networks. SMTP was first defined in RFC 821 ( STD 15) (1982),[and last updated by RFC 5321 (2008) which includes the extended SMTP (ESMTP) additions, and is the protocol in widespread use today. SMTP is specified for outgoing mail transport and uses TCP port 25. Post Office Protocol (POP) is an application-layer Internet standard protocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection. POP and IMAP (Internet Message Access Protocol) are the two most prevalent Internet standard protocols for e-mail retrieval. Virtually all modern e-mail clients and servers support both. The POP protocol has been developed through several versions, with version 3 (POP3) being the current standard. POP3 is used for most webmail services such as G-mail and Yahoo.

9. SMPT VS. POP

10. HTML VS. XML The most important difference between the two markup languages is that HyperText Markup Language , or HTML, is an application of SGML (Standard Generalized Markup Language),and allows an author to omit certain tags and use attribute minimization. The Extensible HyperText Markup Language, or XHTML, is an application of XML (Extensible Markup Language). It doesn’t permit the omission of any tags or the use of attribute minimization. However, it provides a shorthand notation for empty elements—for example, we could use <br/> instead of <br></br>—which HTML does not. A conforming XML document must be well formed, which, among other things, means that there must be an end tag for every start tag, and that nested tags must be closed in the right order.When an XML parser encounters an error relating to the document’s well-formedness, it must abort, whereas an HTML parser is expected to attempt to recover and continue.

11. HTML VS XML

13. Is this relevant to E- BUSINESS? Yes this activity is relevant to electronic business because we must be aware on networking system, how it works and their attributes. We need this awareness or skills by the time that we implement our business what ever it is. I thank YOU!