Computer Network Principles - Essay Example

1 Introduction Internet is the fastest rising technology mankind has ever produced. Helping to navigate through the powerful and fastest growing world of information is a challenge. The integration of computer networks in valuable for the students as well as the school management. Students acquire technology awareness at the initial phase of study (Ramig 2010). The school of computing needs a network which will cope with the future trends and technologies. Lot of educational institutes has implemented a Campus area network. The campus area network connects to two or more local area networks of the educational institutes or universities or corporate campus. The connectivity involves library, departments, student halls of residence (Campus Area Network. 2007).The network devices and computing equipments have to be consistent and extendable, if the faculty staff increases. The school consists of 6 departments. Every department has different requirements, in order to employ network resources. The network layout of the school requires an expandable and efficient network which will fulfill the requirements of the school staff. Network security considerations will also be given for the special laboratories servers and lecturers. The connectivity and access level for each group is not same. Internet connectivity is limited; it means everyone is not allowed to access Internet. Scanners and printers are required by some departments in order to print and scan related documents. The network design with centralized administration is called a client / server architecture. This architecture is best suited for centralized administration. The same network architecture is deployed in the school premises. 2 Requirements of LAN Design The initial stride will is to classify the requirements. This will include the network devices and functionality for fulfilling the requirements for the school staff. The justification of the selected computing devices and the network equipments is required. The second stride includes the network design. The design will clearly identify, floor connections, office connections, servers, workstations, printers, scanners and cable types. The third stride is to implement a Wide Area Network (WAN) to connect other locations or Internet connectivity. 3 Network Requirements 3.1 First Floor The first floor includes Administration, Staff Office and the technical staff. The staff office will access the file server which is the ‘Students notes distribution server’ for uploading notes. Students are facilitated at the same time for downloading the notes. The lecturers will connect their laptops with the wireless access points installed equipped with the new 802.11n technology. Since the demand of high bandwidth multimedia transmission is increasing, improving the (QoS) (Quality of service) is essential. Keeping this in mind a new technology 8.2.11n is introduced by the IEEE (Kuo 2008). For keeping the network robust and efficient 802.11n protocol provides comprehensive support for voice and video services (Cai, Ling et al. 2009). These wireless access points are connected with a Cisco switch. For providing security, Virtual local area network (VLAN) is introduced. The definition of virtual LAN is available on network dictionary which states as “Virtual LAN (VLAN) refers to a logical network in which a group of devices on one or more LANs that are configured so that they can communicate as if they were attached to the same wire, when in fact they are located on a number of different LAN segments” The VLAN will be considered as a broadcast domain. It concludes that the broadcast generates from one computer can only be received to the destination which is defined by some criteria in the broadcast domain (VLANs and Virtual Networking. 1998). The advantages of VLAN implementation includes more efficient way of bandwidth utilization and eliminating the network from possible broadcast storms which may result in denial of service. By using VLANs the capacity of switching technology is utilized to its full potential. VLAN also supports VLAN trunking protocol. The VLAN trunking protocol will significantly reduce administration for the switched network. Considering the future network expansion considerations of the school the requirement for creating new VLAN will be eliminated by using VLAN trunking protocol. The VLAN will split the domain of the lecturers with the other. VLAN uses encryption techniques for transmitting data over the network. Access policy list is configured in the router for defining the routes. The router processes the data packets based on parameters. Internet protocol and subnet is the framework of the router to process the routes on the destination. The policy for lecturers is to access to the file server, printers and email server. In this way, data transmission from the academic domain is secured. No one can identify the wireless network because only lecturer Internet protocol pool is allowed to communicate. If anyone tries to access the wireless network from outside, he or she is prompted to enter the Wired Equivalent Privacy key (WEP). A good definition of WEP is available in the network dictionary which says ” Wired Equivalent Privacy (WEP) is a security protocol, specified in the IEEE Wireless Fidelity (Wi-Fi) standard, 802.11b, that is designed to provide a wireless local area network (WLAN) with a level of security and privacy comparable to what is usually expected of a wired LAN.” WEP provides security by an encryption algorithm. No one in the school can access the wireless network or the lecturers system. A secondary Cisco switch installation has been proposed. Although one access point within a range of approximately 200 feet is enough for connecting 253 laptops. The staff can access the printer on the network. The printer is shared on the network and is visible at “My network places” in case of Microsoft operating systems. The administrative staff needs to access the email server, Microsoft office and the Internet. The team requires full access to the student records for administrative purpose. A new VLAN is created for that purpose. On that VLAN, an access policy is applied for granting access to the file server, Internet and the Email server. For future network expansion, an extra switch is installed with the premises for coping up the network connectivity requirements, if a new system has been placed. Technical staff consists of the school’s servers. A file server, Email server, and a firewall / proxy server are installed. One scanner is also installed for the lecturers. The router and the Wide Area network (WAN) connectivity is terminated in this department. A DSL modem is installed for that purpose. As it is the technical staff team, access to all network devices is granted for administrative and troubleshooting purpose. The router is installed in the technical department and providing connectivity to the second floor of the school premises. 3.2 Second Floor On the second floor, 12 staff offices rooms are available, which are connecting to the wireless access points. The first and second floor shares the same security architecture. 3.3 Third Floor The third floor contains 6 student laboratories. Apart from the two special laboratories, total four laboratories have a capacity of forty students. Each laboratory possesses a laser printer. A network switch needs to be installed in order to access the student network. Before connecting to the network, the student should notify the technical staff to grant them access on the network. The practical and tutorial laboratory consists of servers regarding practical and tutorial material. A separate VLAN is created for the practical and tutorial server in order to protect the network transmission. The other special laboratory containing servers for student projects will use a separate VLAN for securing and encrypting the transmission. The connectivity of the laboratory servers is separated from the network by placing another router. A secondary switch installation is required for supporting the needs of network resources in the future. 4 Implementation of Network Equipments 4.1 Implementing Cables Category 5 cables are used for the data transmission in a proposed network design. CAT-5 is in the form of twisted pairs. This cable consists of 4 copper wire pairs, connecting the network node with RJ 45 connectors.CAT-5 supports up to 100 to 1000 MHz speeds in a full duplex mode (Category 5 Cable. 2007). The length of the cable depends on the distance which needs evaluation in the school premises. 4.2 Implementation of Switches Fast Ethernet Cisco switches supporting VLAN functionality are implemented. As compared to the old 10 base-t, the 100 base-t provides 10 times more speed supporting the MAC and MTU. Almost all network adapters supports 100 base-t technology, making it a cost saving and efficient choice for local area networks (Fast Ethernet. 2007). All the switches are of twenty four ports, keeping in mind the expansion of the network will not affect by purchasing new network equipment. Total six switches are used on the first floor. Only four out of six are operation. Two switches are installed for future expansion of the network. On the second floor, total four switches are used. Three switches are operational and one is installed for future expansion of the network. On the third floor, total nine switches are installed. Seven switches are operational and two switches are installed for future network expansion. 4.3 Implementation of Routers There are total three routers installed for routing the traffic from each floor. The access policies are applied for separating the lecturers, students, and Internet user’s domain. 4.4 Installation of Printers There are total seven laser printers installed in the premises. One printer is installed on the first floor of the school premises, the rest of the six printers are installed on the third floor in each student laboratory. 4.5 Installation of Servers There were total three servers including the file server, email server and the firewall / proxy server. The file server is the student’s notes distribution system. The email server will route the email, inbound and outbound of the school premises. The application layer for accessing email service is “Microsoft outlook express”. The data servers which are located in the two specific laboratories are on a student’s network indicated by blue color Ethernet cables in the network diagram. They are being used for practicals and tutorials, and projects of the students. 4.6 Installation of Access points Access points are seven in total. Three access points are used on the first floor for providing secure wireless connectivity to the laptops of the lecturers. On the second floor, four access points are installed. For keeping in mind, the supporting network resources for network expansion two switches are installed for connecting any new access point in case of new development of the departments and staff hiring. 4.7 Implementation of Wide Area Network A comprehensive definition of wide area networks is available on network dictionary which says “A Wide Area Network (WAN) is a computer network covering multiple distance areas, which may spread across the entire world. WANs often connect multiple smaller networks, such as local area networks (LANs) or metro area networks (MANs)”. For implementing Wide Area network, digital Subscriber line is implemented for catering the needs of the school network. A device used to connect to the telephony company for Internet access (DSL modem. 2010).There is no superior requirement for downloading data from the Internet. The student network runs on the local area network. DSL supports up to 3 Mb/sec downstream speeds in an asynchronous mode means only the downstream. The upstream speed is from 128Kbps to 768 Kbps. 4.8 Support and Maintenance The incident management is catered by the local technical department of the school. Currently only five employees are working. After the implementation of the network, new hiring of a qualified network administrator is required in order to manage the network security related incidents. To troubleshoot issues related to system administration and support, a team is required for performing day to day issues within the school premises. 5 Appendices 5.1 Network Design First Floor 5.2 Network Design Second Floor 5.3 Network Design third Floor 5.4 Bibliography RAMIG, R., 2010. Online Tools for Research--Elementary and Middle School Style. MultiMedia & Internet@Schools, 17(5), pp. 15-17. DSL modem. 2010. Computer Desktop Encyclopedia, , pp. 1. Campus Area Network. 2007. Network Dictionary, , pp. 85-85. Quality of Service. 2007. Network Dictionary, , pp. 397-397. Wide Area Network. 2007. Network Dictionary, , pp. 525-525. Category 5 Cable. 2007. Network Dictionary, , pp. 88-88. Virtual LAN. 2007. Network Dictionary, , pp. 515-515. Fast Ethernet. 2007. Network Dictionary, , pp. 190-190. VLANs and Virtual Networking. 1998. Internetworking LANs & WANs, , pp. 453-494. Wired Equivalent Privacy. 2007. Network Dictionary, , pp. 529-529. CAI, L.X., LING, X., SHEN, X. and MARK, J.W., 2009. Supporting voice and video applications over IEEE 802.11n WLANs. Wireless Networks (10220038), 15(4), pp. 443-454. KUO, W.-., 2008. Traffic scheduling for multimedia transmission over IEEE 802.11e wireless LAN. IET Communications, 2(1), pp. 92-97. Read More