1 00:00:01,260 --> 00:00:04,530 So what is the Cisco quality of service toolset. 2 00:00:04,690 --> 00:00:11,670 The S.R. indie guy discusses the following mechanisms or quality of service tool sets that allow you 3 00:00:11,670 --> 00:00:14,140 to implement quality of service. 4 00:00:14,160 --> 00:00:19,020 This is what is emphasized in the CCMA exam. 5 00:00:19,110 --> 00:00:22,470 The exam talks about marking device trust. 6 00:00:22,500 --> 00:00:27,710 Pro translation shaping policing and congestion management. 7 00:00:27,900 --> 00:00:34,420 And if you look at the mechanisms listed in the s or indeed guide we have classification and mocking 8 00:00:35,040 --> 00:00:43,520 policing and markdown scheduling link specific tools and there are some additional options such as order 9 00:00:43,530 --> 00:00:47,260 cause and called Mission Control. 10 00:00:47,380 --> 00:00:51,070 He has a graphic showing the quality of service toolset. 11 00:00:51,170 --> 00:01:00,530 Now these mechanisms apply to differentiate its services or serve into serve has its own mechanisms 12 00:01:00,890 --> 00:01:01,790 and best effort. 13 00:01:01,790 --> 00:01:04,600 Essentially it doesn't have these mechanisms. 14 00:01:04,610 --> 00:01:08,320 It simply treats all traffic the same. 15 00:01:08,330 --> 00:01:10,630 Firstly we have a mission control. 16 00:01:10,700 --> 00:01:15,300 Will your call as an example be permitted across the IP network. 17 00:01:15,860 --> 00:01:22,790 If there is over subscription of the link a voice call may need to take an alternate path classification 18 00:01:22,790 --> 00:01:28,280 and marking is essentially looking at traffic types and putting them into classes. 19 00:01:28,280 --> 00:01:29,950 So is it voice traffic. 20 00:01:30,020 --> 00:01:33,350 If it is then it goes into a certain class. 21 00:01:33,470 --> 00:01:37,740 Is it video traffic then it would go into a different class. 22 00:01:37,820 --> 00:01:41,940 Is it FCP FCP would go into a third class. 23 00:01:42,170 --> 00:01:44,190 We have policing and markdown. 24 00:01:44,270 --> 00:01:50,570 If you're sending too much traffic your traffic could be dropped or the quality of service given to 25 00:01:50,570 --> 00:01:52,270 you could be lowered. 26 00:01:52,460 --> 00:01:56,060 Then we have scheduling which includes queuing and dropping. 27 00:01:56,060 --> 00:02:04,680 We have traffic shaping and link specific mechanisms we'll start off with classification and marking. 28 00:02:05,060 --> 00:02:14,090 When you send a package with FedEx or DHL that package needs to be marked for next day delivery or urgent 29 00:02:14,120 --> 00:02:22,370 delivery or standard delivery a label gets put onto the package to indicate how important that package 30 00:02:22,370 --> 00:02:27,080 is when the package is sent from one depot to another. 31 00:02:27,110 --> 00:02:32,760 They don't open the package to determine the quality of service that that package would get. 32 00:02:32,780 --> 00:02:40,160 They look at the label and the label determines the quality of service that the package gets in the 33 00:02:40,160 --> 00:02:43,890 same way when a telephone sends packets into a network. 34 00:02:44,000 --> 00:02:51,620 It needs to mark those packets as important so that every switch and router along the path can treat 35 00:02:51,680 --> 00:02:55,810 the packet differently when compared to say FCP sent by. 36 00:02:55,810 --> 00:03:04,640 P.S. so when packets are forwarded from the phone to the first switch it needs to indicate using some 37 00:03:04,640 --> 00:03:09,800 kind of marking or label or field that the packet is important. 38 00:03:09,950 --> 00:03:17,780 It needs to be treated better than say in FTB packet when switch one sends the packet to switch to it 39 00:03:17,780 --> 00:03:24,350 needs to indicate to that switch that the packet is important and in the same way when the second switch 40 00:03:24,350 --> 00:03:30,980 sends the packet to the rudder it needs to indicate to the broader that the packet is of great importance. 41 00:03:30,980 --> 00:03:34,220 Now this introduces the concept of a trust boundary. 42 00:03:34,220 --> 00:03:36,500 Who do we trust in the network. 43 00:03:36,860 --> 00:03:42,320 As an example does the rod of trust switch to the switch to trust. 44 00:03:42,350 --> 00:03:43,530 Which one as an example. 45 00:03:44,150 --> 00:03:50,990 If these devices trust the markings that they receive from each other or the quality of service settings 46 00:03:50,990 --> 00:03:55,950 that they receive from one another then the trust boundary ends over here. 47 00:03:55,970 --> 00:04:02,670 In other words the switch doesn't trust the phone and the switch doesn't trust the P.C.. 48 00:04:02,750 --> 00:04:10,730 If however the switch did trust the phone the trust boundary would be extended to the phone as is the 49 00:04:10,730 --> 00:04:13,710 case with a lot of IP phones. 50 00:04:13,820 --> 00:04:22,170 We could have a P.C. connected to a phone so we could connect to the P.C. to the back of the phone and 51 00:04:22,170 --> 00:04:25,830 in that case the trust boundary would end at the phone. 52 00:04:25,830 --> 00:04:31,910 In other words the switches and the router trust the phone but they don't trust the P.C.. 53 00:04:32,130 --> 00:04:38,580 So if the P.C. sends traffic to the phone telling the phone that its traffic is important the phone 54 00:04:38,580 --> 00:04:40,520 will not trust those markings. 55 00:04:40,800 --> 00:04:48,120 All those values and would override them in the same way switch one doesn't trust the markings or values 56 00:04:48,120 --> 00:04:54,720 sent by the P.C. but it would trust the markings or values sent by the phone and again switch to would 57 00:04:54,720 --> 00:04:58,180 trust what switch one tells it and the writer would trust. 58 00:04:58,200 --> 00:05:06,030 Switch to as an analogy if you go to the airport and your ticket says that you have a first class ticket 59 00:05:06,370 --> 00:05:12,380 you will be treated differently to someone who has a economy class ticket. 60 00:05:12,930 --> 00:05:17,410 But the people at the airport won't accept a ticket that you've just made up. 61 00:05:17,520 --> 00:05:22,430 So if you just printed out your own ticket they're not going to trust that unless they can reference 62 00:05:22,430 --> 00:05:23,160 it officially.