The Security Implications of Virtual Local Area Network VLAN Niger Mills Calabar Nigeria

Virtual local area network (VLAN), is a logical grouping of network users and resources connected to administratively define the operation of activated ports on a switch. The creation of VLAN is saddled with the ability to develop smaller broadcast domain within a layer-2 switching router; by assigning different ports on the switch to different sub networks. The application was a re-design project carried out on the Niger-Mills’ network to improve the operational short falls identified by the operators. Niger-Mills’ LAN network covered a total of 5 departments:: marketing, sales, finance, engineering and management. Five (5) users were randomly sampled and selected from each department to constitute their individual LAN, making a total of 25 computers. The project successfully introduced this process in the Niger-mills LAN as a test run. It was further recommended that switch-model 2950/3560 be introduced to activate this function automatically. From the trouble shooting process, it was obvious that layer-2 switches only read frames for filtering. They don’t access the network layer protocol, and by default, switch forward all broadcast. But the creation and implementation of VLAN, essentially activated a small broadcast domain at layer-2. Based on this framework, the design was modified using six (6) core layer switches with 24 port Cisco catalyst 2950 switch. While the distribution and access switches were D-link switches, with link speed of 100Mb/s. The software, WIRESHARK, was also used to decode packet contents of the interface for readability. Its output was analyzed to verify that the security on the network was enhanced. The introduction of VLAN into Internet-circuit has been able to regulate these practices. Also, VLAN, advantageously built the LAN with multiple broadcast groups and allowed total control of each port and user.