1 00:00:00,060 --> 00:00:00,893 In this lesson, 2 00:00:00,893 --> 00:00:03,780 we'll explore wireless infrastructure security. 3 00:00:03,780 --> 00:00:05,370 Wireless infrastructure security is 4 00:00:05,370 --> 00:00:08,430 a critical aspect of any organization's IT strategy 5 00:00:08,430 --> 00:00:11,430 and as wireless networks have become increasingly widespread 6 00:00:11,430 --> 00:00:13,380 in our organization, it's very important 7 00:00:13,380 --> 00:00:15,870 that you understand how to secure them effectively. 8 00:00:15,870 --> 00:00:18,450 So in this lesson, we will dive into the importance 9 00:00:18,450 --> 00:00:21,690 of wireless access point placement, site surveys 10 00:00:21,690 --> 00:00:23,100 and heat map to ensure 11 00:00:23,100 --> 00:00:25,710 that your wireless infrastructure is secure. 12 00:00:25,710 --> 00:00:28,290 First, let's talk about where your wireless access 13 00:00:28,290 --> 00:00:30,180 points should be placed and installed. 14 00:00:30,180 --> 00:00:33,170 A wireless access point, also known as the WAP 15 00:00:33,170 --> 00:00:35,550 is a device that allows wireless devices to connect 16 00:00:35,550 --> 00:00:39,540 to a wired network using the 802.11 Wi-Fi standards 17 00:00:39,540 --> 00:00:40,440 and protocols. 18 00:00:40,440 --> 00:00:41,273 The placement 19 00:00:41,273 --> 00:00:43,500 of these wireless access points is important to consider 20 00:00:43,500 --> 00:00:45,900 in terms of achieving both optimal network performance 21 00:00:45,900 --> 00:00:48,000 and increased levels of security. 22 00:00:48,000 --> 00:00:50,640 Your wireless access point placement will significantly 23 00:00:50,640 --> 00:00:53,280 impact the range, coverage and the signal strength 24 00:00:53,280 --> 00:00:55,890 of your organization's wireless network. 25 00:00:55,890 --> 00:00:58,620 If you can properly place your wireless access points 26 00:00:58,620 --> 00:01:00,480 you can ensure that your organization's wireless 27 00:01:00,480 --> 00:01:02,340 network will cover the entire physical area 28 00:01:02,340 --> 00:01:04,769 of your office spaces without leaving dead zones 29 00:01:04,769 --> 00:01:07,920 or areas without any coverage by wireless signals. 30 00:01:07,920 --> 00:01:10,560 However, proper access point placement isn't just 31 00:01:10,560 --> 00:01:12,510 about achieving good coverage for your networks. 32 00:01:12,510 --> 00:01:13,950 It's also a huge concern 33 00:01:13,950 --> 00:01:16,920 in terms of wireless security of your wireless network. 34 00:01:16,920 --> 00:01:18,780 If you place the wireless exit point 35 00:01:18,780 --> 00:01:21,690 near a window or an external wall of your facility, 36 00:01:21,690 --> 00:01:23,310 the wireless signal may extend 37 00:01:23,310 --> 00:01:25,800 out past the physical boundaries of your building. 38 00:01:25,800 --> 00:01:28,110 This provides an increased coverage zone that could 39 00:01:28,110 --> 00:01:29,670 allow unauthorized individuals 40 00:01:29,670 --> 00:01:32,370 or threat actors to access your wireless network even 41 00:01:32,370 --> 00:01:34,530 if they are located outside of your facility. 42 00:01:34,530 --> 00:01:37,080 For example, a threat actor could park their car 43 00:01:37,080 --> 00:01:39,060 in your parking lot next to your building 44 00:01:39,060 --> 00:01:41,400 and if an access point is located too close 45 00:01:41,400 --> 00:01:43,020 to the exterior wall of the building 46 00:01:43,020 --> 00:01:46,290 then the wireless network signal could be obtained safely 47 00:01:46,290 --> 00:01:47,910 from the parking lot. 48 00:01:47,910 --> 00:01:50,117 For this reason, you should normally place your wireless 49 00:01:50,117 --> 00:01:52,980 access point near the center of the facility and away 50 00:01:52,980 --> 00:01:55,410 from windows and external walls to minimize the risk 51 00:01:55,410 --> 00:01:56,970 of unauthorized access. 52 00:01:56,970 --> 00:02:00,090 This is especially true if your wireless access points are 53 00:02:00,090 --> 00:02:03,780 using omnidirectional antennas that broadcast the signal 360 54 00:02:03,780 --> 00:02:05,460 degrees in every direction. 55 00:02:05,460 --> 00:02:08,460 Alternatively, if you need to place a wireless access point 56 00:02:08,460 --> 00:02:11,370 on one of your exterior walls, then you should select a 57 00:02:11,370 --> 00:02:14,070 unidirectional antenna that only broadcasts the wireless 58 00:02:14,070 --> 00:02:15,450 signal in one direction. 59 00:02:15,450 --> 00:02:17,010 In works towards your facility 60 00:02:17,010 --> 00:02:19,170 and this will prevent an attacker from gaining access 61 00:02:19,170 --> 00:02:21,900 to the network from your parking lot or other areas outside 62 00:02:21,900 --> 00:02:22,830 of your facilities. 63 00:02:22,830 --> 00:02:25,170 When placing your wireless access point, you should always 64 00:02:25,170 --> 00:02:27,690 place the access point in a higher location, such 65 00:02:27,690 --> 00:02:29,820 as placing it on top of a shelf or mounting it 66 00:02:29,820 --> 00:02:30,780 to the ceiling. 67 00:02:30,780 --> 00:02:33,690 This will help maximize coverage and minimize interference 68 00:02:33,690 --> 00:02:35,040 with your wireless network. 69 00:02:35,040 --> 00:02:37,080 If you're trying to install a wireless network 70 00:02:37,080 --> 00:02:39,090 in a large building, though, you'll not be able to 71 00:02:39,090 --> 00:02:40,920 adequately cover the entire building 72 00:02:40,920 --> 00:02:42,840 with a single wireless access point. 73 00:02:42,840 --> 00:02:45,810 So instead, you need to install them in an extended service 74 00:02:45,810 --> 00:02:48,930 set or ESS configuration where multiple wireless access 75 00:02:48,930 --> 00:02:52,290 points work together to create one large merge coverage zone 76 00:02:52,290 --> 00:02:55,350 across the entire facility and provide seamless coverage 77 00:02:55,350 --> 00:02:57,240 as a user moves throughout the facility 78 00:02:57,240 --> 00:02:59,100 automatically switching from one wireless access 79 00:02:59,100 --> 00:03:00,120 point to another, 80 00:03:00,120 --> 00:03:02,700 while still remaining on the same enterprise network. 81 00:03:02,700 --> 00:03:03,533 When setting 82 00:03:03,533 --> 00:03:05,700 up multiple wireless access points that are working together 83 00:03:05,700 --> 00:03:07,800 in extended service set configuration 84 00:03:07,800 --> 00:03:09,420 it's important that you consider interference 85 00:03:09,420 --> 00:03:12,270 between different wireless access points since they are only 86 00:03:12,270 --> 00:03:15,420 a few channels that most wireless access points can support 87 00:03:15,420 --> 00:03:18,780 and the SEC approved frequency bands for wireless networks. 88 00:03:18,780 --> 00:03:20,280 The two most common types 89 00:03:20,280 --> 00:03:22,380 of interference are co-channel interference 90 00:03:22,380 --> 00:03:24,000 and adjacent channel interference. 91 00:03:24,000 --> 00:03:25,350 With co-channel interference 92 00:03:25,350 --> 00:03:27,000 you start to experience interference 93 00:03:27,000 --> 00:03:29,040 because there are two wireless access points 94 00:03:29,040 --> 00:03:31,920 that are providing overlapping coverage in the same area 95 00:03:31,920 --> 00:03:33,210 and they're using the same channel 96 00:03:33,210 --> 00:03:36,360 or frequency bands to create their coverage areas. 97 00:03:36,360 --> 00:03:37,193 Because 98 00:03:37,193 --> 00:03:39,000 of these two access points using the same frequencies 99 00:03:39,000 --> 00:03:41,850 or channels, it will cause those signals to collide 100 00:03:41,850 --> 00:03:44,070 and then the data must be re-transmitted again 101 00:03:44,070 --> 00:03:47,190 and again until it successfully is transmitted. 102 00:03:47,190 --> 00:03:49,830 This retransmission will slow down your wireless networks 103 00:03:49,830 --> 00:03:51,540 since it is adding additional traffic 104 00:03:51,540 --> 00:03:52,800 to your wireless networks. 105 00:03:52,800 --> 00:03:53,790 On the other hand 106 00:03:53,790 --> 00:03:56,400 adjacent channel interference will occur when 107 00:03:56,400 --> 00:03:57,233 the channel selected 108 00:03:57,233 --> 00:03:59,280 for your adjacent wireless access points do not 109 00:03:59,280 --> 00:04:01,200 have enough space between the channels 110 00:04:01,200 --> 00:04:03,150 which causes some overlapping other frequencies 111 00:04:03,150 --> 00:04:04,710 or signals being transmitted 112 00:04:04,710 --> 00:04:06,210 which can cause a significant number 113 00:04:06,210 --> 00:04:08,040 of errors and loss of bandwidth. 114 00:04:08,040 --> 00:04:10,800 For example, if two access points within range 115 00:04:10,800 --> 00:04:14,370 of one another or configured in the 2.4 gigahertz band 116 00:04:14,370 --> 00:04:17,760 with channels one and six, they will not overlap. 117 00:04:17,760 --> 00:04:20,820 But if a third access point is added using channel three 118 00:04:20,820 --> 00:04:24,600 it will use part of the spectrum used in both of the WAPs 119 00:04:24,600 --> 00:04:27,060 and all three networks will suffer from interference. 120 00:04:27,060 --> 00:04:29,790 This is because in the 2.4 gigahertz band 121 00:04:29,790 --> 00:04:31,530 there are only 11 frequency bands 122 00:04:31,530 --> 00:04:34,080 or channels that are allowed to be used. 123 00:04:34,080 --> 00:04:36,570 Each channel from one to 11 is considered to 124 00:04:36,570 --> 00:04:40,860 be 22 megahertz wide, but there's only a hundred megahertz 125 00:04:40,860 --> 00:04:42,840 of total frequency bands available 126 00:04:42,840 --> 00:04:45,870 so there's a lot of overlap between the different channels. 127 00:04:45,870 --> 00:04:49,560 For example, channel six operates a 22 megahertz channel 128 00:04:49,560 --> 00:04:52,770 centered on 2.437 gigahertz. 129 00:04:52,770 --> 00:04:55,620 This means that there's a strong overlap with channels five 130 00:04:55,620 --> 00:04:58,800 and seven and a little less interference with channels four 131 00:04:58,800 --> 00:04:59,633 and eight. 132 00:04:59,633 --> 00:05:01,350 Since channel six operates at a peak efficiency 133 00:05:01,350 --> 00:05:05,400 of 2.437 gigahertz, but then the strength of the signal 134 00:05:05,400 --> 00:05:07,680 deteriorates and weakens as the signal spreads out 135 00:05:07,680 --> 00:05:11,610 from 2.436 gigahertz to 2.448 gigahertz to 136 00:05:11,610 --> 00:05:15,450 create a circular channel pattern on a frequency chart. 137 00:05:15,450 --> 00:05:18,570 For this reason, you should always select channels one, six 138 00:05:18,570 --> 00:05:21,540 and 11 if you're operating in a 2.4 gigahertz wireless 139 00:05:21,540 --> 00:05:22,530 frequency band. 140 00:05:22,530 --> 00:05:24,690 Since these channels do not overlap with each other 141 00:05:24,690 --> 00:05:27,000 and they will not interfere with each other. 142 00:05:27,000 --> 00:05:29,280 Now that we have a little interference theory covered 143 00:05:29,280 --> 00:05:31,530 let's move into the more practical side of figuring out 144 00:05:31,530 --> 00:05:34,050 if you have interference in your wireless network, and 145 00:05:34,050 --> 00:05:35,970 if your wireless access points have been placed 146 00:05:35,970 --> 00:05:38,820 in the right locations to provide us with the best coverage. 147 00:05:38,820 --> 00:05:40,950 To do this, we'll perform a site survey 148 00:05:40,950 --> 00:05:42,360 and create a heat map. 149 00:05:42,360 --> 00:05:44,070 A site survey is a process of planning 150 00:05:44,070 --> 00:05:46,860 and designing a wireless network to provide a solution 151 00:05:46,860 --> 00:05:49,950 that will deliver the required wireless coverage, data rates 152 00:05:49,950 --> 00:05:52,620 network capacity, roaming capability, and quality 153 00:05:52,620 --> 00:05:53,700 of service levels. 154 00:05:53,700 --> 00:05:54,900 A site survey usually 155 00:05:54,900 --> 00:05:56,520 involves a site visit to test 156 00:05:56,520 --> 00:05:58,170 the radio frequency interference 157 00:05:58,170 --> 00:06:01,320 and to identify optimal installation locations 158 00:06:01,320 --> 00:06:03,450 for access points by scanning the airways 159 00:06:03,450 --> 00:06:06,540 in order to identify any device that is already configured 160 00:06:06,540 --> 00:06:07,470 and is operating 161 00:06:07,470 --> 00:06:10,200 in that wireless frequency band that we are considered using 162 00:06:10,200 --> 00:06:11,310 for our wireless network. 163 00:06:11,310 --> 00:06:12,570 During your site survey 164 00:06:12,570 --> 00:06:15,184 you'll usually create something known as a heat map. 165 00:06:15,184 --> 00:06:17,160 A heat map is a graphical representation 166 00:06:17,160 --> 00:06:18,450 of your wireless coverage 167 00:06:18,450 --> 00:06:20,940 the signal strength and frequency utilization data 168 00:06:20,940 --> 00:06:22,740 at different locations on that map, 169 00:06:22,740 --> 00:06:24,780 with each individual value being represented 170 00:06:24,780 --> 00:06:26,310 as a different color. 171 00:06:26,310 --> 00:06:27,300 Heat maps are really 172 00:06:27,300 --> 00:06:29,610 useful when you're trying to troubleshoot coverage issues 173 00:06:29,610 --> 00:06:32,250 or dead zone areas that have no coverage, as well 174 00:06:32,250 --> 00:06:34,980 as determining any areas where the signal strength is too 175 00:06:34,980 --> 00:06:36,270 strong. 176 00:06:36,270 --> 00:06:38,430 Also, these heat maps are useful 177 00:06:38,430 --> 00:06:40,740 in identifying the areas where your wireless network 178 00:06:40,740 --> 00:06:43,350 signal may be leaking outside of physical boundaries 179 00:06:43,350 --> 00:06:44,940 of the building and could potentially allow 180 00:06:44,940 --> 00:06:48,360 for an attacker to gain unauthorized access to the network. 181 00:06:48,360 --> 00:06:49,920 For example, if you were hired 182 00:06:49,920 --> 00:06:52,110 by a company as a cybersecurity and consultant to 183 00:06:52,110 --> 00:06:54,180 determine the proper configuration and placement 184 00:06:54,180 --> 00:06:56,160 of their wireless network, you should first 185 00:06:56,160 --> 00:06:58,800 conduct a site survey to identify the optimal locations 186 00:06:58,800 --> 00:07:01,290 for the wireless access points by determining what 187 00:07:01,290 --> 00:07:03,960 other wireless networks are already nearby. 188 00:07:03,960 --> 00:07:06,840 Then after installing the new wireless access points 189 00:07:06,840 --> 00:07:08,670 you should create a heat map to visualize the 190 00:07:08,670 --> 00:07:10,470 actual coverage of the network. 191 00:07:10,470 --> 00:07:12,750 The heat map should show that the signal is strong 192 00:07:12,750 --> 00:07:14,610 in the central areas of the building 193 00:07:14,610 --> 00:07:16,410 but weak near the outer edges. 194 00:07:16,410 --> 00:07:20,310 This might indicate that additional WAPs are needed 195 00:07:20,310 --> 00:07:21,720 near the edges of the building 196 00:07:21,720 --> 00:07:23,850 and use some unidirectional antennas to 197 00:07:23,850 --> 00:07:26,010 focus the signal back into the building instead 198 00:07:26,010 --> 00:07:28,020 of letting it leak outside of the building. 199 00:07:28,020 --> 00:07:29,730 On the other hand, at the heat map shows 200 00:07:29,730 --> 00:07:31,740 that the signal is leaking outside the building. 201 00:07:31,740 --> 00:07:34,020 That will indicate that the wireless access points 202 00:07:34,020 --> 00:07:37,020 need to be repositioned to prevent unauthorized access 203 00:07:37,020 --> 00:07:39,420 from outside the building, or the signal strength 204 00:07:39,420 --> 00:07:42,210 of those wireless access points may need to be decreased so 205 00:07:42,210 --> 00:07:45,030 that the signal remains within the walls of your facility. 206 00:07:45,030 --> 00:07:46,710 So remember, the placement 207 00:07:46,710 --> 00:07:49,440 of your organization's wireless access points is crucial 208 00:07:49,440 --> 00:07:51,210 for ensuring the proper network performance 209 00:07:51,210 --> 00:07:53,310 and security for your wireless networks. 210 00:07:53,310 --> 00:07:55,470 The wireless access points should be placed 211 00:07:55,470 --> 00:07:57,270 in central locations within the building 212 00:07:57,270 --> 00:08:01,020 and remain away from the windows and external walls. 213 00:08:01,020 --> 00:08:02,550 A site survey is an essential step 214 00:08:02,550 --> 00:08:04,890 in planning a secure wireless network 215 00:08:04,890 --> 00:08:07,200 and you should create a heat map at the end 216 00:08:07,200 --> 00:08:09,720 of your installation to show a graphical representation 217 00:08:09,720 --> 00:08:10,650 of the coverage area 218 00:08:10,650 --> 00:08:13,350 and strength of your wireless network signals. 219 00:08:13,350 --> 00:08:15,120 These heat maps can then be used 220 00:08:15,120 --> 00:08:18,150 in areas where coverage is too weak, coverage is too strong 221 00:08:18,150 --> 00:08:21,050 or coverage is leaking outside the walls of your facility.