1 00:00:00,720 --> 00:00:07,800 So to configure a port on a switch as a trunk port supporting Cisco IP phones, you would do the following. 2 00:00:09,460 --> 00:00:10,950 So firstly on our switch. 3 00:00:10,960 --> 00:00:15,760 Well, in this case the 500, I'm going to type the command show VLAN. 4 00:00:17,240 --> 00:00:19,340 Switch to see our VLANs. 5 00:00:20,350 --> 00:00:25,120 As you can see here, we've got a default VLAN and we've got our voice VLAN which is VLAN. 6 00:00:25,120 --> 00:00:29,720 Two all interfaces are currently in the native VLAN. 7 00:00:29,740 --> 00:00:31,690 In other words, the default VLAN. 8 00:00:32,369 --> 00:00:42,810 So going into global configuration mode, I can type the command interface range if 0/1/1 up to three. 9 00:00:43,980 --> 00:00:46,230 And then I can type the command switch port. 10 00:00:47,710 --> 00:00:52,630 Trunk encapsulation and then specify an encapsulation. 11 00:00:53,620 --> 00:00:59,620 In the past, we may have chosen eesl or ed to one Q Cisco IP phones only support dot one. 12 00:00:59,620 --> 00:01:02,590 Q So we're going to specify one key. 13 00:01:03,290 --> 00:01:06,350 Then I'm going to say switchboard mode trunk. 14 00:01:06,620 --> 00:01:10,370 To force these ports to trunk and then switchboard. 15 00:01:11,160 --> 00:01:14,610 Trunk native vlan one. 16 00:01:15,750 --> 00:01:21,600 Then I'm going to top switchboard voice VLAN and in our case it's VLAN two. 17 00:01:22,260 --> 00:01:25,350 Topping the command do show run interface. 18 00:01:25,350 --> 00:01:31,530 If 01/1 will show me the running configuration of that specific port. 19 00:01:31,920 --> 00:01:37,260 Now remember, default commands don't show up in the running config, so you won't necessarily see all 20 00:01:37,260 --> 00:01:41,310 the commands we've just typed because some of them are there by default. 21 00:01:41,580 --> 00:01:46,980 But as you can see here, the port is trunking and the voice VLAN is VLAN two. 22 00:01:47,280 --> 00:01:53,010 The problem here is that all VLANs will be allowed across this port, which could potentially cause 23 00:01:53,010 --> 00:01:57,850 that issue where broadcasts affect the processing of Cisco IP phones. 24 00:01:57,870 --> 00:02:00,510 So we should manually prune this trunk. 25 00:02:01,110 --> 00:02:08,610 So I'm going to top the command switchboard trunk allowed VLAN and then I'm going to specify the VLANs 26 00:02:08,610 --> 00:02:09,600 that are allowed. 27 00:02:09,630 --> 00:02:16,230 Now on certain switches, you might only need to specify the voice VLAN, but in the U.S. 500 I'm going 28 00:02:16,230 --> 00:02:21,270 to specify all the default vlans plus the voice vlan. 29 00:02:21,910 --> 00:02:28,240 Not tapping the command du show run and the specific interface shows me that I'm only allowing the native 30 00:02:28,240 --> 00:02:36,310 VLAN VLAN one on ethernet VLAN two, which is my voice VLAN and the other default VLANs supported on 31 00:02:36,310 --> 00:02:37,300 Cisco switches. 32 00:02:37,720 --> 00:02:41,440 So once again do show VLAN switch. 33 00:02:42,500 --> 00:02:48,110 Will allow me to see those default VLANs one is the default for Ethernet and then we have the VLANs 34 00:02:48,110 --> 00:02:50,240 for FTI and token ring. 35 00:02:50,720 --> 00:02:53,510 So that's how you configure an interface to support trunking. 36 00:02:53,510 --> 00:02:58,700 It's no longer recommended, but if you have an older switch, you may need to configure it in this 37 00:02:58,700 --> 00:02:59,240 way. 38 00:02:59,690 --> 00:03:06,590 Lastly, I could tap the command show interface f01/1 switchboard. 39 00:03:08,440 --> 00:03:11,470 I notice you can see here that the administrative mode is shrunk. 40 00:03:11,500 --> 00:03:18,190 The operational mode at the moment is trunk, encapsulation is dot one Q the native VLAN is VLAN one, 41 00:03:18,190 --> 00:03:25,570 which is the default the VLANs enabled across this interface, all 1 to 1000 2 to 1005. 42 00:03:25,900 --> 00:03:28,930 The active VLANs at the moment are VLANs one and two. 43 00:03:29,230 --> 00:03:31,630 The voice VLAN is VLAN two. 44 00:03:33,210 --> 00:03:41,250 The recommended way to implement IP phones in a network infrastructure is to use multiple VLAN access 45 00:03:41,250 --> 00:03:41,910 ports. 46 00:03:42,270 --> 00:03:48,210 In this example, we are configuring the port on the switch as an access port, but still configuring 47 00:03:48,240 --> 00:03:49,890 two VLANs on that port. 48 00:03:50,160 --> 00:03:54,720 The phone will be in the voice VLAN and the PC will be in the data VLAN. 49 00:03:55,230 --> 00:03:57,420 Tag frames will be sent to the phone. 50 00:03:57,870 --> 00:04:00,900 So 801 Q frames are still used. 51 00:04:00,930 --> 00:04:06,270 Even though this is an access port untagged frames are sent to the PC. 52 00:04:06,480 --> 00:04:10,380 Now this flies in the face of what you learned in the CNA course. 53 00:04:10,920 --> 00:04:16,829 In the CNA course we learnt that an access port belongs to a single VLAN. 54 00:04:17,010 --> 00:04:19,620 That is not the case in this scenario. 55 00:04:19,860 --> 00:04:24,810 In this scenario, the access port has two VLANs configured on it. 56 00:04:26,030 --> 00:04:30,260 Now there are multiple advantages to this method of implementation. 57 00:04:30,650 --> 00:04:37,100 The first one is that a multi VLAN access port can be configured as a secure port, unlike the previous 58 00:04:37,100 --> 00:04:39,740 example where we configured the port as a trunk. 59 00:04:40,130 --> 00:04:48,170 The voice vlan id can also be discovered through CDP or LDAP, so the manual configuration of vlans 60 00:04:48,170 --> 00:04:49,880 on the phone is not required. 61 00:04:50,120 --> 00:04:54,050 It also allows for scalability from an IP addressing point of view. 62 00:04:54,320 --> 00:04:56,900 The issue that you may encounter in the real world. 63 00:04:57,800 --> 00:05:05,270 Is that if a Class C address has been allocated to your PCs and let's say using 80% of your addresses. 64 00:05:05,630 --> 00:05:11,660 So 80% of the IP addresses in that subnet have been allocated to physical devices like PCs. 65 00:05:11,660 --> 00:05:14,870 And now you add Cisco IP phones to the mix. 66 00:05:15,260 --> 00:05:21,680 You are essentially doubling the amount of devices that you only have, 20% of the IP addresses remaining 67 00:05:21,680 --> 00:05:22,720 in that subnet. 68 00:05:22,730 --> 00:05:28,310 So you cannot put the phones and the PC in the same subnet without redoing your IP address. 69 00:05:28,850 --> 00:05:34,610 However, if you put your phones into a separate subnet, that doesn't affect the IP addressing of the 70 00:05:34,610 --> 00:05:35,450 PCs. 71 00:05:35,660 --> 00:05:43,460 So you allocate a separate subnet for IP phones, and the IP subnet allocated to the PCS is left alone. 72 00:05:44,730 --> 00:05:48,060 There's also a logical separation of voice and data traffic. 73 00:05:48,570 --> 00:05:51,470 Because the phones are on a separate subnet to the PCs. 74 00:05:51,480 --> 00:05:54,540 It's easier to implement quality of service. 75 00:05:54,900 --> 00:05:59,700 It's easier to implement your access lists, and it's easier to implement security. 76 00:05:59,700 --> 00:06:05,160 So that's a major advantage to separating the phones and the PCs into separate subnets. 77 00:06:05,640 --> 00:06:10,650 Two devices can also be connected to a single port in the switch, which minimizes cabling. 78 00:06:11,390 --> 00:06:17,150 Your PC is physically connected to the phone, which is physically connected to the switch across a 79 00:06:17,150 --> 00:06:18,260 single cable. 80 00:06:18,530 --> 00:06:26,570 However, logically, the phone and the PC are in separate cables because they are in different VLANs. 81 00:06:26,570 --> 00:06:28,880 But physically you saving on cabling. 82 00:06:29,390 --> 00:06:35,630 The multiple VLAN access port implementation tends to be the most common in the real world and is the 83 00:06:35,630 --> 00:06:42,910 recommended way to implement IP phones to configure a multiple VLAN access port on an interface. 84 00:06:42,920 --> 00:06:44,060 Do the following. 85 00:06:44,710 --> 00:06:52,950 So on a U.S. 500 or on our switch I'm going to top the come on show VLAN switch to see the VLANs configured 86 00:06:52,960 --> 00:06:56,660 at the moment we have vlan one configured on ports. 87 00:06:56,680 --> 00:07:00,760 If 01/0 up to f01/8. 88 00:07:01,000 --> 00:07:03,520 No interfaces are in the voice vlan. 89 00:07:04,350 --> 00:07:08,910 I can also do the command show run interface if 01/1. 90 00:07:10,050 --> 00:07:12,450 To show you the configuration on this interface. 91 00:07:13,050 --> 00:07:16,130 As you can see, I've just defaulted the configuration. 92 00:07:16,140 --> 00:07:18,990 All ports are in excess VLAN one. 93 00:07:19,530 --> 00:07:26,100 So going into global config mode and tapping the command interface range of 01/1, two, three. 94 00:07:26,790 --> 00:07:31,890 In other words, we're going to configure the three ports that have our IP phones connected to them. 95 00:07:32,220 --> 00:07:40,500 I cannot type the command switch port mode access making these ports access ports, which is the default. 96 00:07:40,950 --> 00:07:49,200 Then I can tap the command switchboard, the voice vlan two and switchboard access vlan one. 97 00:07:50,590 --> 00:07:52,790 Now tapping the command show run interface. 98 00:07:52,810 --> 00:08:00,070 If 011 shows me that that interface has been configured with a voice VLAN, we don't see the native 99 00:08:00,070 --> 00:08:09,520 VLAN or the data VLAN or the access VLAN because VLAN one is the default VLAN and default configurations 100 00:08:09,520 --> 00:08:17,470 don't show up in the running config, but tapping the command show interface if zero one says one switch 101 00:08:17,470 --> 00:08:18,160 port. 102 00:08:19,020 --> 00:08:23,250 Allows me to see the voice and data VLAN more clearly. 103 00:08:23,700 --> 00:08:31,770 So on this interface it's been configured as a static access port and is acting as a static access port. 104 00:08:32,309 --> 00:08:39,720 The access VLAN is VLAN one the default and notice the voice VLAN is VLAN two. 105 00:08:40,289 --> 00:08:45,090 So even though the operational mode is static access, in other words, this is acting as an access 106 00:08:45,090 --> 00:08:45,720 port. 107 00:08:45,900 --> 00:08:49,710 We are allowing VLANs one and two across this port. 108 00:08:51,570 --> 00:08:58,920 The fourth way to implement IP phones is to use ADA 2.1 P, now 82.1 P frames. 109 00:08:58,920 --> 00:09:06,090 Use the three bits in the ADA 201 CU header to allow for the prioritization of voice traffic over data 110 00:09:06,090 --> 00:09:06,810 traffic. 111 00:09:06,960 --> 00:09:12,720 They are three bits in an edited or one Q header called the costs or class of service bits. 112 00:09:13,050 --> 00:09:14,850 I'll talk more about these later. 113 00:09:15,300 --> 00:09:22,740 Essentially Editor a1p allows for the marking of voice traffic with a value of five in the cost field, 114 00:09:22,980 --> 00:09:28,680 allowing the switch to see voice traffic as higher priority than data traffic. 115 00:09:29,100 --> 00:09:37,230 Now with a single VLAN access port using ADA or one P, the interface is in a single VLAN, so both 116 00:09:37,230 --> 00:09:41,250 the phone and the PC are in VLAN two. 117 00:09:41,580 --> 00:09:49,710 But the phone is going to send tagged frames to the switch now because this is a standard access port. 118 00:09:49,740 --> 00:09:58,560 The phone uses a special VLAN number in the edited or one Q header to allow for the use of 80 21q frames. 119 00:09:59,930 --> 00:10:07,400 Now just to recap from the CCNA course, a standard Ethernet frame has a source and destination field, 120 00:10:07,400 --> 00:10:14,120 a length or either type the data and then a frame check sequence when edited or one Q is used. 121 00:10:14,120 --> 00:10:20,690 A tag is inserted between the source and destination address and the length and either type field. 122 00:10:21,080 --> 00:10:23,570 That tag consists of four bytes. 123 00:10:24,020 --> 00:10:33,110 16 bits is the tag protocol identifier and then the remaining 16 bits consist of the priority code point 124 00:10:33,200 --> 00:10:43,940 or priority field, the canonical format indicator and the vlan id now editor r1p specifies the meaning 125 00:10:43,940 --> 00:10:48,500 of the priority field or class of service or cost field. 126 00:10:49,100 --> 00:10:52,910 The priority code point field is three bits in length. 127 00:10:53,330 --> 00:11:01,850 In other words, the binary values are from 000 to 111, and decimal values is 0 to 7. 128 00:11:02,120 --> 00:11:07,910 The higher the priority value, the more important the traffic and thus voice will have a binary value 129 00:11:07,910 --> 00:11:12,290 of 101 or the equivalent decimal value of five. 130 00:11:12,710 --> 00:11:22,100 So the phone is sending edited or one q frames to the switch on an access port with the cost field or 131 00:11:22,100 --> 00:11:25,640 priority code point field set to five. 132 00:11:25,640 --> 00:11:29,990 In other words, it's sending an edit two to the one p frame to the switch. 133 00:11:30,590 --> 00:11:38,990 Now just to reiterate terminology and edit 201q header is inserted in the Ethernet frame, which looks 134 00:11:38,990 --> 00:11:39,890 as follows. 135 00:11:40,100 --> 00:11:47,690 Edit 201p denotes the meaning or values of the priority field or cost field. 136 00:11:48,170 --> 00:11:54,080 The value specified here form part of the recommendations of edit 2 to 1 p. 137 00:11:54,200 --> 00:12:01,940 So once again editor or one P specifies the different classes or values of the priority field in an 138 00:12:01,940 --> 00:12:03,710 802 to 1 Q header. 139 00:12:04,930 --> 00:12:10,930 The phone is setting the value of the cost field to five when sending frames to the switch. 140 00:12:11,230 --> 00:12:16,960 The switch therefore knows that traffic from the phone has a higher priority than traffic from the PC. 141 00:12:17,020 --> 00:12:21,100 Now that explains how editorial one PPI can be used for quality of service. 142 00:12:21,370 --> 00:12:24,200 But in this example, this is an access port. 143 00:12:24,220 --> 00:12:27,340 In other words, it's not a trunk port, it's an access port. 144 00:12:27,460 --> 00:12:30,250 Only one VLAN has been configured on this port. 145 00:12:30,250 --> 00:12:31,300 VLAN two. 146 00:12:31,690 --> 00:12:38,410 So when sending traffic to the switch, a VLAN number has to be specified by the phone and the VLAN 147 00:12:38,410 --> 00:12:41,530 number used in this case is VLAN zero. 148 00:12:42,700 --> 00:12:49,660 The switch therefore knows that when it receives an edit to the one Q frame with the VLAN number set 149 00:12:49,660 --> 00:12:57,400 to zero that the phone still belongs to the VLAN configured on this port as the access VLAN. 150 00:12:57,730 --> 00:13:03,550 So all traffic from the phone and the PC reside in VLAN two. 151 00:13:03,880 --> 00:13:07,090 The phone is not in a separate VLAN to the PC. 152 00:13:07,120 --> 00:13:09,550 They both belong to VLAN two. 153 00:13:09,910 --> 00:13:19,390 Thus the use of the special VLAN of zero when sending ed or one q frames to the switch on this access 154 00:13:19,390 --> 00:13:20,020 port. 155 00:13:20,650 --> 00:13:26,680 So to configure ATO 2.1 p on an axis port, you need to do the following. 156 00:13:27,530 --> 00:13:32,270 So before configuring the switch or the U.S. 500, let's have a look at our VLANs. 157 00:13:33,410 --> 00:13:38,450 So as you can see here, all interfaces on the default VLAN of VLAN one. 158 00:13:39,100 --> 00:13:41,670 Once again show run interface. 159 00:13:41,680 --> 00:13:48,550 If 011 shows us that the interface has a default configuration on it. 160 00:13:49,710 --> 00:13:55,770 Going into global config mode typing interface range f01/123. 161 00:13:56,960 --> 00:13:59,840 The interfaces that have our phones connected to them. 162 00:14:00,200 --> 00:14:08,270 I can tap the command switch port mode access so these ports are not going to be configured as trunks. 163 00:14:08,450 --> 00:14:10,550 They configured as access ports. 164 00:14:11,270 --> 00:14:12,200 Switch port. 165 00:14:13,380 --> 00:14:23,460 Voice vlan dot one p to specify the use of dot one p on these ports switch port. 166 00:14:24,340 --> 00:14:27,250 Access VLAN two. 167 00:14:28,930 --> 00:14:31,810 Notice we're not specifying a voice vlan of two. 168 00:14:31,840 --> 00:14:35,020 We are specifying an access vlan of two. 169 00:14:35,530 --> 00:14:40,270 So once again, show run interface f01/1. 170 00:14:40,720 --> 00:14:43,390 Shows me that this port is in VLAN two. 171 00:14:44,080 --> 00:14:50,200 It's an access port, but we are using ED or one P on this interface. 172 00:14:50,740 --> 00:14:59,560 The phones will transmit traffic to the switch as tagged frames using VLAN zero in the VLAN identifier. 173 00:15:00,390 --> 00:15:04,140 Both the phone and the PC are in VLAN two. 174 00:15:06,510 --> 00:15:12,090 That concludes part one of our discussion of the Cisco IP phone startup process. 175 00:15:12,240 --> 00:15:19,740 We discussed how an IP phone obtains power, how VLAN information is provided to the phone using CDP 176 00:15:19,800 --> 00:15:21,360 or LDPE. 177 00:15:21,930 --> 00:15:27,480 In the next part, we're going to continue the discussion by looking at how an IP phone acquires an 178 00:15:27,480 --> 00:15:34,030 IP address, downloads its firmware and configuration, and registers with a Q CM. 179 00:15:34,440 --> 00:15:38,330 We'll also discuss the signaling protocols of skinny and sip. 180 00:15:39,240 --> 00:15:40,410 Thank you for watching.