proxy server


6. What is proxy server?

Proxy server sits between a client application, such as a Web browser, and a real server.
It intercepts all requests to the real server to see if it can fulfill the requests itself. If not, it
forwards the request to the real server.

Proxy servers have two main purposes:

Improve Performance: Proxy servers can dramatically improve performance for groups
of users. This is because it saves the results of all requests for a certain amount of time.
Consider the case where both user X and user Y access the World Wide Web through a
proxy server.

First user X requests a certain Web page, which we'll call Page 1. Sometime later, user Y
requests the same page. Instead of forwarding the request to the Web server where Page
1 resides, which can be a time-consuming operation, the proxy server simply returns the
Page 1 that it already fetched for user X.

Filter Requests: Proxy servers can also be used to filter requests. For example, a company
might use a proxy server to prevent its employees from accessing a specific set of Web
sites.

7. If you can not receive emails:

- Check your Incoming Mail (POP3) settings.

- Make sure that you use the full email address not just the first part of the email address
For example: janedoe@comentum.com and not just "janedoe".

- Login to your Web Mail and Delete any suspicious email that can block your Mailbox.
(emails that have no "From" or corrupted spam emails can cause Outlook/Outlook
Express to hang.

- Check Bulk and Spam folders.

- Check whether you have reached your storage limit.

- There are many reported issues on newly installed or existing Firewall/Anti-Virus/
Anti-Spam softwares which are misconfigured and are causing problems sending and
receiving emails. You may want to disable these types of software in your computer
temporarily to see if your email problems go away. If this fixes your issue, try updating/
re-installing or re-configuring your Firewall/Anti-Virus/Anti-Spam software correctly.

8. If you can not send emails:

- Check your Outgoing Mail (SMTP) setting.

9. Microsoft Outlook vs. Outlook Express

Outlook Express is the Internet e-mail and news reader included with Microsoft
Internet Explorer version 4.0 and later. It was formerly called Internet Mail and News.
While it shares the Outlook name, Outlook Express doesn't have the task- and contact-
management capabilities of Microsoft Outlook, nor can it handle e-mail other than
Internet mail.

Microsoft Outlook is a full-featured Personal Information Manager (PIM) application that
lets you store information such as Contacts (Address Book), Calendar (Date Book), Tasks
(To Do List) and Notes (Memo Pad). It also acts as an email application, connecting with
a standard POP3 mail server or a corporate Microsoft Exchange mail server. Outlook
usually appears in a business or organizational setting; rarely is it used primarily as a
personal email solution.

Outlook Express is a free email application that connects with a standard POP3 mail
server only. It is bundled with Internet Explorer. Outlook Express usually appears in a
personal or home setting. It does not include the full-featured PIM elements that are part
of Microsoft Outlook.

10. What is TCP/IP?

Transmission Control Protocol/Internet Protocol, is the basic communications protocols
used to connect hosts on the Internet.

A communication protocol is a description of the rules computers must follow to
communicate with each other. The Internet communication protocol defines the rules for
computer communication over the Internet.