An extranet is a controlled private network that allows access to partners, vendors and suppliers or an authorized set of customers normally to a subset of the information accessible from an organization’s intranet. An extranet is similar to a DMZ in that it provides access to needed services for authorized parties, without granting access to an organization’s entire network. An extranet is a private network organization.
Historically the term was occasionally also used in the sense of two organizations sharing their internal networks over a VPN.
During the late 1990s and early 2000s, several industries started to use the term ‘extranet’ to describe centralized repositories of shared data (and supporting applications) made accessible via the web only to authorized members of particular work groups – for example, geographically dispersed, multi-company project teams. Some applications are offered on a software as a service (SaaS) basis.
Advantage of Extranet
- Exchange large volumes of data using Electronic Data Interchange (EDI)
- Share product catalogs exclusively with trade partners
- Collaborate with other companies on joint development efforts
- Jointly develop and use training programs with other companies
- Provide or access services provided by one company to a group of other companies, such as an online banking application managed by one company on behalf of affiliated banks.
Disadvantage of Extranet
- Extranets can be expensive to implement and maintain within an organization (e.g., hardware, software, employee training costs), if hosted internally rather than by an application service provider.
- Security of extranets can be a concern when hosting valuable or proprietary information.
Issues in Extranet
Apart for advantages there are also some issues associated with extranet. These issues are discussed below:
- Hosting
Where the extranet pages will be held i.e. who will host the extranet pages. In this context there are two choices:
- Host it on your own server.
Host it with an Internet Service Provider (ISP) in the same way as web pages.
But hosting extranet pages on your own server requires high bandwidth internet connection which is very costly.
- Security
Additional firewall security is required if you host extranet pages on your own server which result in a complex security mechanism and increase work load.
- Accessing Issues
Information cannot be accessed without internet connection. However, information can be accessed in Intranet without internet connection.
- Decreased Interaction
It decreases the face to face interaction in the business which results in lack of communication among customers, business partners and suppliers.