Scenario 1: Network topology selection and device configuration
- The network topology that EBiz.com is configured in is star topology (Besta and Hoefler, 2014). Therefore, an extended star topology would be the best choice. Star topology is an excellent topology with high rate of flexibility however, if the wiring in the network needs to be upgraded and or replaced then an extended star topology would be better. In the given scenario, the office building consists of three floors. The network design could be such that each floor will contain a switch. All the computers will be connected to the switch. The switch of each floor will be connected to a central switch through optical fibers (Diebold and Y?lmaz, 2014). EBiz.com has 250 computers and 5 switches. Therefore, the design would be such that each floor will have 1 switch or maximum of 2 switches. Around 85 computers will be connected to one switch. The switches should be capable of future expansion.
- Server based network would be best suitable for the above design. This would increase the speed and allow easy reconfiguration of the networks (Liang et al., 2014). Peer to peer based network will significantly slow down the speed of data transfer when the number of computers connected to the network increases (Bolognani et al., 2013). This is because in peer-to-peer network data packets will have to travel all the nodes in the network. Nodes are the computers connected to network.
- The company has 250 computers and 5 servers. The building has three floors. Therefore, 1 server will be installed in each floor and around 85 computers will be connected to each server. The servers in each floor will be connected to a central switch that will control the entire network.
- The central switch or router is the easiest to configure (Mardedi and Rosidi, 2015). Deletion or expansion of network is done through this central point. However, it has the disadvantage of central point failure (Rohden Sorge Witthaut and Timme, 2014). The meaning of the above said words is that if the central server breakdowns then the whole network will be disrupted ((Espina et al., 2014)). This can cause a serious problem in the network and all the computers connected to the network will become idle.
- The network diagram for the above design will be as follows:
Figure 1. Extended star network design
(Source: Created by author)
- The IP address will have 5 subnets (Schemitsch, 2013). The subnets with different hosts are listed as below:
150, 90, 30, 20 and 10 hosts.
- The subnet mask of 192.168.10.0/24 is given as below:
Various steps need to be followed to calculate the subnet mask of a network number. The steps are as follows:
Step 1. Converting the network number into a binary number.
Step 2. Calculating the number of ones in the subnet mask from the IP address.
Step 3. Calculating the host range.
Step 4. Calculating the total number of subnets and hosts in each subnet.
Following the above said methods of the subnet mask is calculated as follows:
192 . 168 . 10 . 0
11111111 . 11111111 . 11111111 . 00000000
255 . 255 . 255 . 0
There should be 24 ones as the per the network number.
- A number of subnet mask can be created by using the CIDR /24. However, in this case 7 subnets can be created.
- The network addresses that will be created are listed below:
Network number in CIDR |
Host address range |
192. 168. 10. 0 / 25 |
192. 168. 10. 0 – 192. 168. 10. 127 |
192. 168. 10. 0 / 26 |
192. 168. 10. 0 –192. 168. 10. 63 |
192. 168. 10. 0 / 27 |
192. 168. 10. 0 – 192.168. 10. 31 |
192. 168. 10. 0 / 28 |
192. 168. 10. 0 – 192. 168. 10. 15 |
192. 168. 10. 0 / 29 |
192. 168. 10. 0 – 192. 168. 10. 7 |
192. 168. 10. 0 / 30 |
192. 168. 10. 0 – 192. 168. 10. 3 |
192. 168. 10. 0 / 31 |
192. 168. 10. 0 – 192. 168. 10. 1 |
The CIDR of the given address 197. 14. 88. 0 will be 197. 14. 88. 0 / 24. According to the scenario, the network number will be able to work for 10 to 13 addresses each. The size of a subnet mask has to be to the power of 2, and consists of two reserved addresses one for the subnet ID and the other for broadcast address (Dey Ahmed and Ahmmed, 2015). Subnet with an address will be required in by the ISP. 10 and 13 both can be represented as 2^3 and 2^4, therefore, the size of the subnets will have to be atleast 2^4. This will address 16 addresses. Therefore, for 16 customers, 256 addresses are available. The subnets will be 197. 14. 88. [ n * 16 ] / 28, n is the number of customers. In this case, the number of customers is 16. First usable address is 197. 14. 88. [ n * 16 + 1 ] and the last will be 197. 14. 88. [ n * 16 + 14 ]. ISP can reach the internet that the other 13 customers are leaving by using the first address as the gateway for the customer. The address for broadcasting will be will be 197. 14. 88. [ n * 16 + 15 ]. The subnet mask will be as follows:
11111111. 11111111. 11110000
This is the binary representation. The decimal representation will be 255. 255. 255. 240
The first four subnets will be as follows:
- 14. 88. 0 / 28
- 14. 88. 16 / 28
- 14. 88. 32 / 28
- 14. 88. 48 / 28
The above subnets have been represented as decimal number. All the subnets belong to class C as the original IP address is a Class C address.
References:
Besta, M., and Hoefler, T., 2014, November. Slim fly: A cost effective low-diameter network topology. In Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis (pp. 348-359). IEEE Press.
Bolognani, S., Bof, N., Michelotti, D., Muraro, R., and Schenato, L., 2013, December. Identification of power distribution network topology via voltage correlation analysis. In Decision and Control (CDC), 2013 IEEE 52nd Annual Conference on(pp. 1659-1664). IEEE.
Dey, G. K., Ahmed, M. M., and Ahmmed, K. T., 2015, November. Performance analysis and redistribution among RIPv2, EIGRP & OSPF Routing Protocol. In Computer and Information Engineering (ICCIE), 2015 1st International Conference on (pp. 21-24). IEEE.
Diebold, F. X., and Y?lmaz, K., 2014. On the network topology of variance decompositions: Measuring the connectedness of financial firms. Journal of Econometrics, 182(1), 119-134.
Diekmann, C., Michaelis, J., Haslbeck, M., and Carle, G., 2016, May. Verified iptables firewall analysis. In IFIP Networking Conference (IFIP Networking) and Workshops, 2016 (pp. 252-260). IEEE.
Espina, J., Falck, T., Panousopoulou, A., Schmitt, L., Mülhens, O., and Yang, G. Z., 2014. Network topologies, communication protocols, and standards. In Body sensor networks (pp. 189-236). Springer, London.
Liang, W., Yu, H., Zhang, X., Yang, M., Weijie, X. U., Wang, J., … and Zhijia, Y. A. N. G., 2014. U.S. Patent No. 8,730,838. Washington, DC: U.S. Patent and Trademark Office.
Mardedi, L. Z. A., and Rosidi, A., 2015. Developing Computer Network Based on EIGRP Performance Comparison and OSPF. IJACSA. International Journal of Advanced Computer Science and Applications, 6(9), 80-86.
Rohden, M., Sorge, A., Witthaut, D., and Timme, M., 2014. Impact of network topology on synchrony of oscillatory power grids. Chaos: An Interdisciplinary Journal of Nonlinear Science, 24(1), 013123.
Schemitsch, R. R., 2013. U.S. Patent No. 8,578,034. Washington, DC: U.S. Patent and Trademark Office.
Thomas, M., Metcalf, L., Spring, J., Krystosek, P., and Prevost, K., 2014, June. SiLK: A tool suite for unsampled network flow analysis at scale. In Big Data (BigData Congress), 2014 IEEE International Congress on (pp. 184-191). IEEE.