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In this lecture I'd like 2

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to talk about WiFi Bands. 3

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The band of a network 4

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defines what frequency it 5

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can use to broadcast the signal. 6

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This means it also defines 7

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the frequency that the clients 8

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or the computers need to be able 9

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to support and use in order to 10

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be able to connect this network. 11

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The two main frequencies used in 12

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WiFi networks are 2.4 and 5 gigzhertz. 13

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Now previously, when we use airodump-ng 14

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we were only sniffing on 15

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the 2.4 gigahertz frequency. 16

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You can see first of all 17

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my wireless adapter is in 18

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monitor mode mon0 in here. 19

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So if I just do airodump-ng mon0 20

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you'll see that I can get the 21

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wireless networks around me. 22

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But you might have noticed that 23

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you won't actually see all the networks 24

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around you when you run airodump-ng. 25

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I'm gonna control-c this 26

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and if I go here to 27

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my normal host machine 28

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and it actually has a 29

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built in wireless adapter 30

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so it's not as strong 31

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as my alpha adapter. 32

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But if I look for networks, 33

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you'll see I actually have 34

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much more networks in here. 35

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And mainly I have networks and 36

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in here and the name by 5G. 37

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Now the network doesn't have 38

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to necessarily end in 5G 39

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but here in Ireland if 40

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a network broadcasts over five gigahertz 41

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the service provider adds 42

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5G to the network name. 43

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But we also have other networks 44

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broadcasting over 5G 45

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that don't end in 5G. 46

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But basically the main point that 47

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I want to talk about is I'm not able 48

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to see all the networks around me 49

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in here in airodump-ng. 50

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And the reason for this is 51

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because airodump-ng is only sniffing 52

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on 2.0 gigahertz frequency. 53

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So if you do this and you don't 54

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see all the networks around you, 55

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or if you're sniffing 56

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on your own network, 57

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but you don't see all the clients 58

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in your network it's possible 59

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that your routers is 60

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broadcasting over two bands, 61

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over 2.4 and five gigahertz. 62

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And if you're not seeing 63

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the router at all, 64

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if you are not seeing the network 65

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at all like what's happening 66

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here for me, then the router 67

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is probably just broadcasting 68

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over five gigahertz. 69

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Now this doesn't mean that 70

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your wireless adapter is not good. 71

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it just literally means that 72

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this adapter is not able to 73

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see five gigahertz frequency. 74

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It's just outside of its limit, 75

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outside of its reach. 76

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The main problem with five gigahertz 77

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is that, there are a lot 78

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of wireless adapters that can 79

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see it and can communicate with it. 80

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But not many of them support 81

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monitor mode and packet injection. 82

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So you might see me and other people 83

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recommending wireless adapters like 84

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Alpha AWUS0360NHA 85

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This is my most favorite wireless adapter. 86

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I use it all the time, even now. 87

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But the problem with that adapter is 88

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it doesn't pick up five gigahertz frequency. 89

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So it doesn't mean that that adapter is bad 90

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it just means that it can't see 91

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five gigahertz frequency. 92

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Like I said, there aren't many 93

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wireless adapters that support five gigahertz, 94

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but I have an adapter here it's Alpha AWUS0360ACH 95

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and this adapter supports both 96

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2.4 gigahertz and five gigahertz frequencies. 97

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It's not as good as the Alpha 98

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but it does the job. 99

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Now if you want more information about 100

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wireless adapters check out 101

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the link in the resources. 102

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I'm not going to talk a lot about 103

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what wireless adapters do. 104

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But in this lecture I wanna show you 105

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how to sniff and discover five gigahertz 106

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frequency networks and then so that 107

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you can use all the attacks that you've 108

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learned in my other lecture and 109

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in my previous videos with 110

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five gigahertz networks. 111

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So, the adapter that I'm using right now 112

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supports five gigahertz but 113

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as you can see, I still 114

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can't pick up these networks. 115

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That's because I need to specifically 116

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tell airodump-ng that I want you 117

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to listen on five gigahertz frequencies 118

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and five gigahertz channels. 119

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To do that, all we have to do is 120

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just do airodump-ng like we always do 121

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and then we are gonna use a new argument 122

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that we haven't see before and 123

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this argument is called band. 124

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And we're gonna tell it that I want 125

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you to sniff on band A 126

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and that's the band that 127

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supports five gigahertz frequency. 128

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And then I'm just going to give it 129

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the name of my wireless adapter 130

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in monitor mode which is Mon0. 131

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So the command is very simple. 132

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It's very similar to what 133

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we have used before. 134

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And all we have to do 135

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is just type in airodump-ng 136

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followed by the band and 137

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that band that we want to use is A 138

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and we're following that with 139

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our wireless interface. 140

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So I'm gonna hit enter, 141

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and as you can see as soon 142

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as we hit this I'm actually just 143

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gonna do control C now 'cause 144

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you can see the results. 145

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You can see that we got much more 146

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networks right now and we have 147

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the five gigahertz networks. 148

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So we have this network and 149

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this network that we 150

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weren't able to see. 151

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We have the JamesSmithWhiskey 152

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newtwork as well. 153

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And basically we're able to capture 154

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all the networks that use the 155

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five gigahertz frequency. 156

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Now what you can also do, 157

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let me clear the screen. 158

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You can specify multiple bands 159

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using the band argument. 160

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So again, using the same command, 161

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instead of just saying band A, 162

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we can do band a-b-g 163

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and what this will do is 164

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it will tell airodump-ng to capture data 165

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on both 2.4 and five gigahertz frequencies 166

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at the same time. 167

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So let me show you. 168

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So as you can see right here 169

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we're capturing some 2.4 gigahertz networks 170

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and we're capturing five gigahertz networks 171

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as well at the same time. 172

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and we'll also be able to discover 173

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clients connecting to both bands. 174

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The only problem with using 175

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airodump like this is first of all, 176

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you need a powerful 177

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wireless adapter to do this. 178

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Also it will be slightly slower 179

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than only sniffing on one band. 180

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Because when you're sniffing on 181

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two bands you have a lot of channels 182

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that airodump-ng has to hop on 183

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all of them and discover clients 184

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and networks broadcasting on these channels. 185

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So, if you want quicker results 186

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then you're better off specifying the band A, 187

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when you want to sniff on the 188

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five gigahertz frequencies and just 189

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not specify the band when sniffing on 2.4. 190

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But, as you can see you can 191

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just run the command like so, 192

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with band a-b-g and this way you'll 193

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be able to capture data sent over 194

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2.4 and five gigahertz frequencies. 195

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Also keep in mind, in order to sniff data 196

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on five gigahertz frequency, like I said 197

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your wireless adapter needs to 198

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be able to support this band. 199

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So simply adding the band argument 200

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will not work unless your wireless adapter 201

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can support and can sniff data on this band. 202

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One more thing that I wanna note, 203

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I've actually said this before. 204

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If you run airodump-ng against a network 205

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and you see some devices missing 206

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then there is a high chance that these devices 207

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are connected over five gigahertz. 208

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So again, use the band A and then 209

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you should be able to see these devices.