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Communications Infrastructure Week 9 Wireless Ap Configuration

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Communications Infrastructure Week 9 Wireless AP Configuration Figure 1 Linksys WRT54GC Figure 2 Belkin USB Network Adapter My setup at home includes a Linksys Compact Wireless WRT54GC Router (Figure 1 above). This is connected to a Motorola SurfBoard Cable Modem and my own PC (PC1) via a wired Ethernet connection. The kids’s PC (PC2) has a Belkin Wireless G USB Network Adapter (Figure 2 above) which allows them to share the internet connection. I was able to set up the IP details as required and was able to ping from each PC to the other and view the web config of the AP from PC2 as shown in Figures 3 and 4. Figure 3 Pinging PC2 from PC1 Figure 4 Accessing the Linksys web config from PC2 Figure 5 Configuring WEP I configured WEP on the wireless router as shown in figure 5 and was able to verify this on the wireless client (Figure 6). The presence of neighbouring networks outlines the need for security. Figure 6 Wireless Client showing WEP-enabled AP WEP (Wired Equivalent Privacy) facilitates two methods of authentication – open system and shared key. In the former no real authentication occurs and in the latter it is possible to ascertain the static WEP key by capturing the four handshake frames. According to the USB adapter literature only WEP is supported but discussions on a few boards suggested that WPA (Wi-Fi Protected Access) and WPA2 are also supported. They recommended using Windows to control access to the wireless network and downloading a Windows update (KB893357). This generated another tab in the Network Connection Properties shown in Figure 7 where I was able to configure WPA2 with AES (Advanced Encryption Standard)(Figure 8). Figure 9 shows configuration on the router. The router crashed during initial WPA2 configuration and a reboot reinstated the default SSID of ‘linksys’. Figure 7 New Tab in Network Properties Figure 8 Configuring WPA2 on wireless client Figure 9 Configuring WPA2 on router WPA2 implements the mandatory elements of 802.11i. In particular, in addition to TKIP (Temporal Key Integrity Protocol) and the Michael algorithm, it introduces a new AES-based algorithm, CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code Protocol), that is considered fully secure. PSK (Pre-shared key) mode, also known as Personal mode, is designed for home and small office networks that don’t require the complexity of an 802.1X authentication server. Each user enters a passphrase in order to access the network. For full protection a truly random passphrase of at least twenty characters should be used and some recommend at least thirty three.