1 00:00:00,520 --> 00:00:08,820 In the section we're going to talk about BGP basics and applications running protocols are basically 2 00:00:08,820 --> 00:00:18,150 divided into IGMP and Egypt as you know as it can be understood from the name I keep these are the protocols 3 00:00:18,150 --> 00:00:25,070 used in the internal network and AGP is a general name for the Pericles to use. 4 00:00:25,120 --> 00:00:27,310 But when it works in other net. 5 00:00:27,390 --> 00:00:39,300 In other words between different autonomic systems to get the protocol BGP is also an AGP DGP is very 6 00:00:39,300 --> 00:00:48,480 different from IGP routing protocols as the working mechanism I use criteria called metric to reach 7 00:00:48,540 --> 00:00:52,250 at Target that from one point to another. 8 00:00:52,350 --> 00:01:02,360 For example Ripp uses the metric hop count or SPF and Elijah first try to find the first line and preferred 9 00:01:02,370 --> 00:01:11,640 that but by taking a loop to the bandwidth delay or something like that unlike BGP it's the polis seabeds 10 00:01:11,660 --> 00:01:20,990 running protocol that allows you to control traffic flow using many different features. 11 00:01:21,000 --> 00:01:30,180 The main purpose of BGP is to perform routing between different autonomous systems without the loop 12 00:01:30,510 --> 00:01:35,240 as you can see in our figure we have two systems. 13 00:01:35,270 --> 00:01:46,480 And if you want to share the route between these two it on ARM systems we can use BGP many different 14 00:01:46,480 --> 00:01:55,870 permissions can be used for BGP path selection but if none of these per milliards are configured BGP 15 00:01:55,870 --> 00:02:06,460 behaves like RIP and decide on the number of hops past the hope count means a number in terminology 16 00:02:06,550 --> 00:02:08,090 of BJP. 17 00:02:08,340 --> 00:02:23,110 So let's say the ich ISP has different autonomous number as four and as five let's say that 18 00:02:28,730 --> 00:02:41,780 HQ wants to reach to branch and if I don't configure any BGP attribute the thing I'm going to just look 19 00:02:41,820 --> 00:02:44,810 is the last number that I am passing. 20 00:02:45,260 --> 00:02:59,110 So the rote will be in that direction because I'm just passing I asked the to and oh I'm sure I speak 21 00:02:59,110 --> 00:03:05,080 4 and 5 let's say and they're going to be 23. 22 00:03:05,280 --> 00:03:11,240 I'm just passing I asked before an ISP Phife I'm passing through space. 23 00:03:11,810 --> 00:03:20,160 But any year I'm passing Three-Eyes space so distraught will be perfect. 24 00:03:20,160 --> 00:03:28,110 All right let's take a look to the tables that we are using in BGP we have BGP table neighbored table 25 00:03:28,170 --> 00:03:36,850 and periodic table neighbored table consists of all BGP call for your neighbors. 26 00:03:37,030 --> 00:03:47,190 And please keep in mind that guys neighbors are configured manually on BGP BGP table contains all BGP 27 00:03:47,190 --> 00:03:47,680 routes. 28 00:03:47,730 --> 00:03:57,500 And this table can be very very large sometimes and running table contains the best paths for the destination 29 00:03:57,530 --> 00:04:02,070 networks as happened on the other protocols. 30 00:04:02,070 --> 00:04:10,490 And lastly we are going to focus on the BGP message types the first messages open after the neighbor 31 00:04:10,490 --> 00:04:19,110 who rather is recognized it wants to initiate the neighborhood by sending their rather open message 32 00:04:19,680 --> 00:04:21,640 with this message. 33 00:04:21,650 --> 00:04:33,100 The two rather start the BGP appearing and the second message type is keeping alive to peers periodically 34 00:04:33,110 --> 00:04:35,520 send this message to each other. 35 00:04:35,600 --> 00:04:37,670 Keep alive message is sound. 36 00:04:37,690 --> 00:04:48,200 Air is six the second and with this message the BJP neighborhood remains active and we update my search 37 00:04:48,440 --> 00:04:57,260 running informations sent between two neighbored to peer others and network information is contained 38 00:04:57,410 --> 00:05:05,210 in this update in our search and we have lastly a notification message and this is a message sent by 39 00:05:05,600 --> 00:05:10,700 Pyrenean growlers when there is a problem with the not for cations message. 40 00:05:10,700 --> 00:05:14,480 The neighborhood builder pier is and.