1 00:00:00,470 --> 00:00:08,060 OK, so before we talk about how to expand the sniffing space, let me explain the active network devices 2 00:00:08,060 --> 00:00:09,890 and the brooders hubs and switches. 3 00:00:11,690 --> 00:00:18,590 Hub is commonly used to connect segments of a land, which is a local area network and a hub, contains 4 00:00:18,590 --> 00:00:22,700 multiple ports when a packet arrives at one port. 5 00:00:22,730 --> 00:00:29,120 It is copied to the other ports so that all the segments of the land can see all of the packets. 6 00:00:30,270 --> 00:00:35,400 Hub act as a common connection point for devices and a network. 7 00:00:37,510 --> 00:00:46,210 Now, Switch operates at the datalink layer, layer two and sometimes the network layer, which is layer 8 00:00:46,210 --> 00:00:48,970 three of the OSI reference model. 9 00:00:49,820 --> 00:00:53,120 And therefore support any packett protocol. 10 00:00:54,150 --> 00:01:01,050 A LANSAT use switches to join segments are called switch lands, or in the case of Ethernet networks, 11 00:01:01,050 --> 00:01:05,580 switched Ethernet plans in basically all networks. 12 00:01:05,850 --> 00:01:11,580 Switch is a device that filters and forwards packets between LAN segments. 13 00:01:12,960 --> 00:01:19,740 A router is connected to at least two networks, commonly to LANs or Wens, which are the wide area 14 00:01:19,740 --> 00:01:25,200 network or LAN and its ISP, which is the Internet Service Providers Network. 15 00:01:26,320 --> 00:01:32,410 Router is generally located at Gateways, the places where two or more networks connect. 16 00:01:33,570 --> 00:01:40,890 Using headers and forwarding tables, router determines the best path for forwarding the packets, and 17 00:01:40,890 --> 00:01:48,300 in addition, the router also uses protocols such as ICMP Internet control message protocol to communicate 18 00:01:48,300 --> 00:01:53,270 with each other and configures the best route between any two hosts. 19 00:01:53,610 --> 00:02:00,570 So in a word, router, forewords, data packets along networks. 20 00:02:02,170 --> 00:02:08,590 Now, let's compare the hub and the switch, since both of these two devices have similar roles on the 21 00:02:08,590 --> 00:02:09,130 network. 22 00:02:10,120 --> 00:02:16,780 Each serves as a central connection for all of your network equipment and handles a data type known 23 00:02:16,780 --> 00:02:17,770 as frames. 24 00:02:18,460 --> 00:02:20,770 Frames carry your data. 25 00:02:21,700 --> 00:02:28,990 When a frame is received, it is amplified and then transmitted onto the port of the destination PC, 26 00:02:29,020 --> 00:02:31,150 which is typically a personal computer. 27 00:02:32,180 --> 00:02:39,380 The big difference between a hub and a switch is in the method in which frames are being delivered. 28 00:02:39,990 --> 00:02:41,960 Got that in a hub. 29 00:02:42,680 --> 00:02:47,720 A frame is passed along or broadcast to every one of its ports. 30 00:02:47,900 --> 00:02:51,320 It doesn't matter that the frame is only destined for one port. 31 00:02:52,180 --> 00:02:57,010 The hub has no way of distinguishing which port a frame should be sent to, right? 32 00:02:57,950 --> 00:03:03,030 So passing it along to every port ensures that it will reach its intended destination. 33 00:03:03,800 --> 00:03:08,920 Now, this places a lot of traffic on the network and can lead to poor network response times. 34 00:03:08,930 --> 00:03:10,300 You can only imagine, right? 35 00:03:11,060 --> 00:03:18,260 Besides, the frame is received by the unintended nodes, which could be hackers and in a cyber security 36 00:03:18,260 --> 00:03:18,840 point of view. 37 00:03:19,220 --> 00:03:21,650 What about the confidentiality? 38 00:03:22,640 --> 00:03:29,930 And additionally, on a ten one hundred megabit per system hub, it must share its bandwidth with each 39 00:03:29,930 --> 00:03:31,140 and every one of its ports. 40 00:03:31,370 --> 00:03:38,150 So when only one PC is broadcasting, it will have access to the maximum available bandwidth. 41 00:03:38,690 --> 00:03:45,380 However, if there are multiple pieces broadcasting, then that bandwidth will need to be divided among 42 00:03:45,410 --> 00:03:49,700 all of those systems, which will degrade performance for everybody. 43 00:03:50,930 --> 00:03:58,640 So in comparison, a switch keeps a record of the Mac, which is the media access control address of 44 00:03:58,640 --> 00:04:06,380 all the devices connected to it, with this information, a switch can identify which system is sitting 45 00:04:06,380 --> 00:04:07,280 on which port. 46 00:04:08,420 --> 00:04:16,010 So when a frame has received, it knows exactly which port to be sent to without significantly increasing 47 00:04:16,010 --> 00:04:23,600 network response times, and in addition, unlike a hub, a 10 100 megabits per second switch will allocate 48 00:04:23,600 --> 00:04:26,950 a full 10 100 megabits per second to each of its ports. 49 00:04:27,320 --> 00:04:33,920 So regardless of the number of pieces transmitting, users will always have access to the maximum amount 50 00:04:33,920 --> 00:04:35,630 of bandwidth that's important. 51 00:04:36,020 --> 00:04:41,600 So it's for these reasons that a switch is considered to be, well, let's say, a much better choice 52 00:04:41,600 --> 00:04:42,080 than a hub. 53 00:04:42,090 --> 00:04:43,700 Right, good.