Importance of a Network Design - Essay Example

Full Paper Project Scope Calling You Inc. provides assistance on the phone for various companies. The company has decided to deploy a data communication network to support their business functions. The two offices of Calling You Inc. will share a dedicated T1 link. However, each office consists of sixty workstations with Internet access, access to centralized services, VPN and VOIP. The company provides 24 / 7 services and the staff rotates in terms of shifts supporting eight management offices. As there is no legacy data communication network, every stage defines the requirements along with implementation of network components and services. 2 Objectives of the Network The network for Calling You Inc. must meet these objectives: 2.1 Integration The requirement is to synchronize two office of the company with a dedicated T1 link 2.2 Enhanced Voice Support The requirement is to implement a data communication network supporting voice over the network to reduce cost and improve efficiency. 2.3 Scalability The network must support virtual private network in order to establish connections and secure Internet for remote workers of the company. 2.4 Centralized Shared Resources The Company provides 24 / 7 support, staff rotates in shifts, centralized administration is recommended to configure multiple accounts on each workstation, and this enables every employee to log in the computer with his / her own credentials. 3 Network Topology Topology is the framework of any network. Star topology is recommended for the current network design. It is the most widely adopted topology. The star topology supports the centralized provision of network resources and services. The support staff can manage the network administrative and troubleshooting tasks centrally. Star topology helps to implement centralized security architecture for improved and enhanced security of the network. The network implementation cost can be saved by provisioning the core systems located centrally. The security controls and backup systems are also located centrally for better troubleshooting and management. 4 Dedicated T1 Line Data communication network requires a carrier for transportation of data. A simple definition is available on ‘www. T1definition.com’ that says “A T-1 line is a dedicated data line that transmits data at the speed of 1.544 megabits per second (mbps). This translates to a speed that is 27 times faster than a 56k dial-up modem, which means that multiple people can access the Internet simultaneously”. T1 consists of total 24 channels that can be used as 24 different channels for voice or data. However, 24 simultaneously logical connections can be established. A dedicated T1 line can support up to 50 to 100 users on the network. 5 Network Design Figure 1.1 5.1 CAT 5 The dedicated T1 carrier is implemented to synchronize traffic within the two remote sites for Calling You Inc. Furthermore, another carrier is requisite for internal communication of the network. Data transmission is conducted on a Category 5 cables for the current network design. CAT-5 is in the form of twisted pairs. However, the cable consists of 4 copper wire pairs, connecting the network node with RJ 45 connectors. In addition, CAT-5 supports up to 100 to 1000 MHz speeds in a full-duplex mode (#.2007). 5.2 Routers Router is the core components of any network. It performs administrative and traffic distribution tasks. A router is a core computing and packet processing devices in the computer network. Router connects two or more networks with different subnets, enabling the networks to expand on an enterprise level. Logically the router builds a routing table, where it stores all the route addresses. The company requires a synchronization of two networks with geographically located two offices as shown in Fig 1.1. Router on each site will redirect the traffic of both networks over the dedicated T1 link as a carrier. 5.3 Switches Network dictionary defines switch as “A network switch is a device that joins multiple computers together at a low-level network protocol layer. Technically, network switches operate at layer two (Data Link Layer) of the OSI model”. For internal voice and data communication, fast Ethernet switches are recommended. However, the switch redirects the traffic to the router for broadcasting it on the WAN. 5.4 Firewall Firewall is a technology that is deployed for securing the network from intruders, hackers, viruses etc. The presence of a Firewall on the network is vital to secure data and the internal network for any potential threats. 5.5 Server In order to fulfill the requirements of personalized shared resources, Microsoft Active Directory is recommended. Active directory enables the freedom for sharing the same workstation with personal login credentials for each employee. Furthermore, active directory provides centralized administration of shared resources over LAN, MAN and WAN. 5.6 IP Phones Internal communication of VOIP will be supported by CAT 5 cable. Manageable switches will assign IP address to each IP phone by dynamic host configuration protocol (DHCP). As IP phones will connect to the network directly, each IP Phone will be configured by an IP address. 5.7 VPN For creating a VPN session between office network and the remote user, Internet connectivity is mandatory at both ends. Remote users will use a dialer to connect the office network. The VPN configuration will be conducted on the server to accept ‘incoming VPN request’ from remote users. Users may create a VPN session by entering correct username and password. 5.8 Workstations The manageable switch will assign different IP addresses to each workstation by configuring DHCP. However, the communication with the remote office will be conducted by the dedicated T1 which is connected to the routers of these two sites as shown in Fig 1.1. 5.9 WAN To cater the bandwidth requirements along with VOIP support ADSL connectivity is recommended. There is no superior requirement for downloading data from the Internet. The goal of the network is to support VOIP calls. 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, which is sufficient for the network’s bandwidth requirements. 6 Protocol Exploitation & Justification 6.1 Internet Protocol Internet protocol (IP) is the primary protocol for communication between computing devices over a network. It was developed in the 1970’s and is used together with transmission control protocol (TCP) (IP - what is IP (internet protocol)?). Every component on the network requires an IP address for communication. In the current network design, following devices are configured with at least one IP address. Workstations Switches Routers Servers IP Phones ADSL Modem 6.2 Address Resolution Protocol/ Reverse Address Resolution Protocol The address resolution protocol (ARP) identifies the destination of a specific workstation. For example, ‘Workstation A’ wants to send data to ‘Workstation B’. ‘Workstation A’ is located on ‘Site 1’, and ‘Workstation B’ is located at ‘Site 2’. The request from ‘Site A’ will ask the network gateway of Site 2, to identify the workstation in order to deliver the data. The network gateway will instruct the ARP to identify the specific workstation by matching MAC address and IP address. The reverse address resolution protocol (RARP) involves a request from the workstation, in order to enquire its MAC address and IP address from the network’s gateway. 6.3 Internet Control Message Protocol This protocol is executed for troubleshooting issues on the network. For example, if ‘Workstation 1’ cannot access the folder shared by’ Workstation 2’, ping command is executed from the command prompt with the syntax “ping [destination IP address]”. ICMP sends an echo request to check availability of the destination node in terms of time intervals. 6.4 Transmission Control Protocol The transmission control protocol operates on top of IP in order to ensure reliable delivery of data packets. TCP is a connection-oriented protocol. Furthermore, it “enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent” (What is TCP? - A word definition from the webopedia computer dictionary).TCP appends efficiency to the Calling You Inc. data communication network by requesting missing or corrupt packets from the source. 6.5 User Datagram Protocol User datagram protocol does not ensure the delivery of each data packet. There is no retrieval for any corrupt or missing data packet. VOIP is the primary business requirement for the company. VOIP is executed to make IP based voice calls and operates on UDP. File sharing between workstations via file transfer protocol (FTP) also operated on UDP. 6.6 Simple Main Transfer Protocol Simple mail transfer protocol sends and receives electronic email messages. SMTP is supported by two other protocols post office protocol (POP 3) and internet message access protocol (IMAP). POP 3 stores email when the user is in an offline mode. For example, night shift staff receiving emails on day time. Therefore, the emails cannot be downloaded as the user is not available and stored in a queue. When the night staff comes to work, they can download all emails by POP 3 that were received when they were not present. IMAP access emails that are available on the email server queue. 6.7 Hyper Text Transfer Protocol Hyper text transfer protocol is the fundamental protocol which maneuvers on the World Wide Web. HTTP classifies the transmission of messages along with the format. For example, an employee wants to access a website; the first step is to enter URL in the browser. As soon as the user hits enter, the request from the web browser sends HTTP request to the web server for retrieving and displaying the contents of the website. 6.8 Domain Name System Domain name system translates IP addresses in to domain names. The domain names are translated in to meaningful words. For example, 192.168.0.2 is the identification of ‘Calling You Inc.’ domain on the network, DNS translates it in to ‘callingyou.com’ that is more understandable and easy to memorize. 6.9 Dynamic Host Configuration Protocol A simple illustration of the most basic functionality is available at ‘www.kb.iu.edu’ which says “Dynamic Host Configuration Protocol (DHCP) is a network protocol that enables a server to automatically assign an IP address to a computer from a defined range of numbers (i.e., a scope) configured for a given network” (What is DHCP? - knowledge base ). For ‘Calling You Inc.’, DHCP is configured on each switch to automatically assign IP addresses to each workstation and IP phone. References Gast, M.T1: A survival guide Beijing; OReilly, c2001. #. (2007). Network Dictionary, , 1-13. IP - what is IP (internet protocol)? Retrieved 1/24/2011, 2011, from http://compnetworking.about.com/od/networkprotocolsip/g/ip_protocol.htm What is TCP? - A word definition from the webopedia computer dictionary Retrieved 1/24/2011, 2011, from http://www.webopedia.com/TERM/T/TCP.html What is DHCP? - knowledge base Retrieved 1/25/2011, 2011, from http://kb.iu.edu/data/adov.html Read More