Internet and Intranet System Development

 

Introduction to Intranet

- Intranet is a private network that is designed within an enterprise.
- The staffs of the enterprise only have access to the network.
- It is a medium through which the services of the organization are provided to the staffs for fluent organizational operations, which can not be accessed by other people over Internet.

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Benefits and Drawbacks of Intranet

Comparison of Internet, Intranet and Extranet in terms of benefits and drawbacks

 

Intranet:
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1. Intranet is a private network designed for a large organization to share resources within that organization.
2. It makes use of Internet technologies but is isolated from the global Internet.
3. It provides easy, economical and fast way of communication within an organization.
4. It restricts the use of resources for the people outside the network, which provides higher security to the available shared resources within an organization.
5. If proper security measures like firewalls or gateway are not applied, there is risk of loss of privacy or alteration of sensitive organizational data, that may put the organization at risk.

 

 

Internet
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1. Internet is a public network that is accessible by all the people in the world with Internet access.
2. It uses Internet protocols to link resources across the globe.
3. It enables the user to access information from anywhere in the world without any need of geographical constraints.
4. It also helps in online shopping, messaging, easy sharing and communication.
5. The drawbacks of Internet are spams, malwares, leakage of private information, addiction and non-relevant contents exposure.

 

 

Extranet
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1. Extranet is the Intranet that is accessible to some authorized personnel outside the network.
2. It is a network that is shared by two or more orgnizations.
3. It helps the organization by effectively collaborating with the clients and customers.
4. The major problem of an extranet is the security. 
5. It decreases physical communication with the customers.

 

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Content Design, Development, Publishing and Management

Content

Content is the information that resides within a web site. It may include text, image, video, animation and so on. The quality of the web page is determined by the quality of the content it contains and the way of presenting the content within the page.

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Content Filtering

- Content filtering is the process of controlling what content is permitted to the user.
- It is generally used to restrict the material delivered over the Internet via web or mail.
- It determines what content to make available and what content to block.

Methods of Content Filtering
Refer to http://www.egnitenotes.com/note/information-system/control-audit-and-security-of-information-system/#Content Control / Content Filtering for more information on methods of content filtering.

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Packet Filtering vs Content Filtering

1. Packet filtering is a security mechanism at network layer. Content filtering is a security mechanism at transport and application layer.
2. Packet filtering is done by firewalls. Content filtering is performed by applications such as browsers.
3. Packet filtering only checks address and port for authorization. Content filtering checks the content in addition.

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Content Delivery Network (CDN)

- Content Delivery Network is a system of distributed servers that deliver pages and other web resources to the user based on the geographic locations of the user and the content delivery server.
- It helps to speed up the delivery of the content of the websites with high traffic.
- The closer the CDN server is, the faster the content will be delivered to the user.

Working of CDN and Proxy CDN
- The website makes the request.
- The CDN server that is nearest to the requesting location response to the request.
- The CDN copies the pages of the website to a network of servers that are dispersed in geographically different locations.
- This means the contents of the page is cached in the CDN network.
- Whenever the request is made which is the part of the CDN network, it will redirect the request from originating site's server to the CDN server closer to the user.
- This process is nearly transparent to the users.

Benefits of Proxy CDN
- Easy to configure
- Update content as requested
- Optimal for content provider with high traffic

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Content Management System (CMS)

- Content management system is a computer application that is used to create, manage and modify digital contents.
- A content management system is composed of two components:
1. Content Management Application
2. Content Delivery Application

- A content management application is responsible to provide user interface for the user so that the user can create, manage and modify the contents.
- A content delivery application is responsible to compile the changes in the contents and update the web site based on the new contents.

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Intranet Design with Open Source Tools: JUMLA, DRUPAL

JOOMLA

- Joomla is a free open source content management system for publishing web contents.
- It is built on a MVC web application framework.
- The features of Joomla for intranet web application design are as follows:
1. It is mobile friendly.
2. It provides templates for user interface design.
3. It is flexible and fully extensible.
4. It provides support for multi-user permission levels.

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DRUPAL

- Drupal is a free and open source content management system that helps to organize, manage and publish the web contents.

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Tunneling Protocols: VPN

Tunneling

- Tunnelling is the process by which user can access or provide a network service that the underlying network does not support directly.
- It allows a foreign protocol to run over a network which is not supported directly.
- For eg: running IPv4 over IPv6.

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VPN

- Virtual Private Network is a technology that creates a encrypted connection over a less secure network like Internet.
- It allows remote users and branch offices to securely access corporate applications and other resources securely.
- A secure tunnel is used to transmit data.
- The user must use authentication method via passwords or other tokens to gain access to VPN.
- It ensures appropriate level of security to the connected components.
- The performance of VPN is affected by the Internet connection of client, protocol used by ISP and encryption type used by VPN.
- The security protocols used by VPN are as follows:
1. IPSec
2. SSL
3. Point-to-Point Tunneling Protocol
4. Layer 2 Tunneling Protocol