An intranet represents a private computer network within an organization or an institution that facilitate secure sharing of information and network applications within an organization; through offering access to the network’s resources. The network of an organization can be segmented to facilitate its easy implementation and ease of network management. Segmentation involves the division of the larger intranet into smaller sub networks that are linked. The functionality of an intranet is primarily dependent on the internet protocol. The intranet uses the same concepts of the internet as its building blocks for instance the client-server computing model (Casad, 2004). The intranet can be viewed from the same analogy as the internet but confined within an organization and having restricted access to its applications and resources. The uses of intranets vary diversely according to the various needs of an organization. Some of its primary uses include sharing and securing corporate information over the company’s network, facilitation of network applications for instance collaboration which is very important during teleconferencing (Casad, 2004). A typical structure for an intranet with a single access point to the internet can be represented by the figure1 below:
Back bone cable/switch INTERNET
During the design and implementation of an intranet, many factors must be put into consideration. Some of the issues that must be considered include: the size of the intranet with regard to the number of the network segments in the intranet and the total number of individual work stations, the need to have access to the internet, the need to webhost implying that one must have to implement at least 1 DNS server in their network, and the various network applications and resources that the network will make use of (Casad, 2004). The design needs should basically meet your requirements and objectives you expect to get from the intranet.
Domain Name systems (DNS)
The Domain Name System servers represents a dedicated computer on the intranet whose task is to join the Domain Name System which a standardized technology that is used for the management of website names and a variety of internet domains. The Domain name servers run customized networking application; it has a public IP address; an IP address that is visible to all the other network domains on the internet, and contains information on all the other available network names and network hosts.
The DNS is used to convert the human friendly domain names of websites and internet domains such as www.facebook.com into an IP address such as 220.127.116.11 that the connecting nodes of a communication system can understand. The DNS facilitates the assigning of the different domain names to various internet resources irrespective of their physical locations. This is to the advantage of the user because the use of the URL (uniform resource locator) is more user friendly compared to the use of IP addresses to locate the various internet resources. The DNS also store other information such as the list of mail servers that can accept and send mail to and from the different mailing platforms. Through the provision of a world wide a worldwide and distributed redirection services based on key-words, the DNS forms an essential part of the internet and thus the intranet.
The Domain Name Servers can employ the use if static IP address; one is permanently assigned to the DNS server during its configuration and is not subject to change under the network influences, or Dynamic IP address; which changes frequently according to the state of the network, when using this approach, the DNS server is configured to obtain its IP address after a thorough analysis of the network state.
The internet is basically divided into two major name spaces: the domain name systems and the IP address platform. The function of the DNS servers is to synchronize communication between these two platforms( Ron,2005). The figure 2 below best illustrates this logic.
The formulation of Domain Names employs a standardized hierarchical structure whereby the domain name is divided into 3 major parts:
- Top level design which is represented by the right most label for instance in www.facecook.com the top level design is represented by com.
- The sub-domain of the top level design represented by each move to the left of the top level design. In facebook.com, the www represents the sub domain of the com.
- Domain registers.
The figure 3 below represents an example of a domain space.
Figure 3. Source: Windows server cookbook 2005.
Benefits of using the DNS
One of the advantages of using the DNS is that naming system used in the DNS is user friendly compared to the IP address referencing platform. Users tend to be consistent with systems that employ the use of natural language in its design. Labels used in the DNS are familiar and therefore facilitating usability of the network resources and applications. Users find it easier to remember domain names that complex IP addresses.
Another benefit that accompanies the implementation of a DNS is that there is consistency in the DNS names compared to IP addresses. This consistency is achieved due to its hierarchal structure and the standardization of the top level designs such as com, edu, org and so on. Many users find it easy to draw a relationship between the domain name and the relevant content contained in the internet resource (Robbie, 2005). This consistency in the DNS is a key advantage that DNS has over the IP address referencing.
With connection to the internet, using DNS comes as an added advantage because the naming system uses the conventional internet naming methods. DNS is easy to use compared to other servers such as the proxy servers and the print server whose functionality primarily depends on the configuration of IP addresses (Robbie, 2005).
Challenges in management and configuration of DNS
Configuration and management of DNS present a challenge for any organization irrespective of its size; this implies that creating and maintaining a DNS is expensive in terms of hardware, software and the amount of time required configuring the DNS (Craig, 2002).The complexities that accompany the implementation of DNS raises security concerns because the DNS forms the primary access point between the network and the external world. Its weakness therefore presents a potential entry into the network by external hackers and malicious applications from other networks (Craig, 2002).
Casad, J. (2004)Sams teach yourself TCP/IP in 24 hours. New York: Sams Publishing. Pp 10-25.
Craig, H. (2002). TCP/IP network administration. New Jersey: O’Reilly Media, Inc. pp. 69-85
Robbie, A. (2005). Windows server cookbook. New Jersey: O’Reilly Media, Inc. pp 85-125.
Ron ,A. (2005). Pro DNS and BIND. New York: Apress, 2005. Pp 156-191.