BGP options connectintg to Internet - Video By Sikandar Shaik || Dual CCIE (RS/SP) # 35012

[Music] now we are ready to get into some more details about the BGP here so if you remember in our previous video we have learned some of the basics of BGP where we started with autonomous system number I BGP and BGP differences and then BGP features loop dimension mechanism and when to use BGP and when not to use HP because it's something what we have seen number of first video now we are going to continue from there now in this video we are going to learn the different types of ISP connections so depending upon the size of the company depending upon the company's requirement we can have different types of connections to ISP and we have something called single home dual home multihoming dual multihoming connections will try to see the differences between these connections and in which type of connection which type of routing or which type of BGP configuration is more appropriate we will try to look into that and then finally we will see if you are connecting to ISP let's say I am connecting to is p/yr BGP route what are the different methods we try to connect okay that's what again we'll see more in detail about that like we can have three different options with default routes and some specific routes and exchanging all the odds so we'll see these two majorly in this video of training so first we'll start with the type of ISP connections so the first one is single home connection now if you remember in the previous video I already discussed single home so in a single home environment we have just one exit path so this is my autonomous system number let's say is autonomous system number 80 it's connecting to my service folder which is my ISP one and I just got only one connection so in this type of connection we can just have a single default route I can go to this route or I can simply say IP route 0 0 0 0 0 0 0 0 and whatever the next stop let's say the next stop is 1.1 1.2 and then from the ISP side he is going to configure a static route for the public IP whatever we are using here so it's just a normal simple default configurations what we did in our basics is hearing so in this section in this single home environment it's really not recommended to run BGP we just have a site with a single ISP connection and this is fine that doesn't that do not that doesn't depend heavily on the internet or the man connection so here we can use the static route which is most commonly used or even you can use some of the that's what we just simply see your default route to the ISP a second connection we have something called dual homing environment now this is something more common in most of the companies who are not running BGP we generally have two links by connecting to service borders now what is the advantage we get connecting to two links the main advantage we get here is if any one of the link fails like what we'll do is we'll go to this router and I am going to say IP route 0 0 0 0 here also 0 0 0 0 I will say next stop address is 1 dot one dot one dot two which is my first link and I am going to configure one more default route on the same router I'm going to say IP road 0 0 0 0 0 0 0 and then I am going to say to door to door flow to with some different address registers now by default it will use the first link because of administer distance default is 1 if that primary link sells it is going to use the second link now the main advantage we get in this deal home side connection is we cater a tendency the major advantage now we can do like this here as well where you might be connecting to two different routers or you may have a connection to two different routers also for a tenancy and we generally done some HS RP v RR p GL v p to have multiple gateways again in the land so that is something different types of configurations and then that's how we do in case of dual homing and in this scenario also it's not really recommended to use BGP so we are not going to run any BGP because we are just connecting to the same service border so if any one of the link fails only the backup link is used and very less we can do path manipulation you can see you very list we can do pass translation so in this scenario also it's not recommended to use BGP now but when it comes to multihoming environment like in this scenario we can use BGP here now when you have a multihoming environment where you got to exit paths from the same is this is - it's connecting to is p1 and 22 is p2 and I can tell some part of the traffic let's say I got 4 networks like it took example 10 or 10 12 20 dot Network 30 or net flow for your network and I can tell that tend on May 12 2009 it works should use the primary ISP and the remaining two which is my Caridad Network can use alternate secondary ISP and in case if this link fails then everyone goes through secondary link so this is what we can do some part manipulations where we can decide how the traffic should enter there is or exit that is we call this as path manipulation so in this type of scenarios BGP is more typically used and we generally exchange the routes in this scenario we're not simply getting the default route or we are not sending only the default route here instead we are also exchanging all the routes from the service border through bgp protocol but in case of previous two different networks we are just sending the default route in any unknown packet will be sent to ISP and s we will return back that packet based on the static route but here we are trying to exchange all the routes through bgp or maybe some specific routes and then we have something called dil home environment in this dual environment it's just an addition of extra links between the same it's just the same thing which has got some extra links which will provide more redundancy the most redundancy and again here also we can do some use from BGP go do some path manipulations so these are the four different types of implementations we can use and especially in the first two networks the first two types BGP is not really recommended because in the first two scenarios what we do is we simply configure a default route like default routing if you remember the basic default routing in the basic CCNA studies and from the isp side we get a static default or static route for the public IP because our router also do some math translations that's how it works but whereas in case of the remaining two setups we are not only connecting to ISP one for a tenancy we are going to connect to ISP to also so that I can also use I can tell that some of the networks should go from here and the remaining networks should go from here if you want to move that path manipulation within your ace we need to run BGP anyways so this four is going to run BGP now you need to have a registered ace number and based on that a system where I can I can exchange the route between from the service folder and I can do some path manipulation where I will decide how my routes or how my network should go to the Internet why are these fruit of that room so there is something what we get if we are using BGP especially in the big size networks they use BGP for these things or if you are working for a service for derp you may have some customers with these type of connections you may need to do some path manipulation that okay for the customer one they should exit from one path and for the customer to it should use the alternate path so that's something really very useful the bishop is designed for that only so next thing we need to understand is the next thing is we need to understand how we are going to connect to the service for and what how we are going to exchange the routes now there are three different methods of exchanging the routes or communicating with the service folder or routes a communicating to Internet so one option we can just have a single default route and the next option is we can have some more specific routes and the default route and the third option is we can have a complete routing table now how it is going to work so I got some diagrams here so these diagrams looks a bit much complicated so I'll try to make it simple here by using my own diagrams here you can see so what I am going to do is this is my autonomous system number and I got plenty of routers more than 50 60 routers connecting in mice and my ace number is 65,000 65,000 sub number and I'm going to connect to two different ISPs already I have taken some two links from is p1 and is p2 ok so one option is what I can do is if I want to communicate with my internet or if I want to communicate with any outside is now one option I can simply do is I can simply use a single default sort that is something what I can do I can simply go to my router and I can say I can configure a default route here pointing towards is p1 and then from the ISP he will confer the static route and then that default or I will redistribute into my IGP now based on the ICP same thing I will do here also I will point a default out here and from is vv already we have a static route and that static route i will redistribute into BGP and now I'm getting the default route from both the sides I am getting the default route from both the sides so based on the IGP metric like OSPF EIGRP it is going to use any one default route as my primary route if that route goes down then automatically it is going to use the second route that is the first option now there is an advantage with this option and there is also one of the disadvantage here now the advantage with this first type of implementation is we don't really need to know the routes let's say I am going to try to access Yahoo server or Gmail server on the internet I really no need to maintain any information about that Yahoo or Gmail so what I am going to maintain is I am going to maintain just a default on so any unknown packet will be sent to ISP and I say will take care to forwarded Yahoo and your communication will start happening between them that's a very good advantage with that we don't have enough means if you don't have enough resources you can really try this but the drawback is we cannot do any path manipulations so partment elation is not possible in this scenario because even though you are going to use to devolve routes it's going to use any one of the route as primary route based on IGP metric and if that primary route fails then only it is going to use the alternate route it is something not possible right that is the main disadvantage here so now it depends upon like it's a very good option especially if you don't have enough resources in your network you don't have high-speed routers to maintain the routes to run BGP you can simply go on with this option this is really useful especially applicable for small size to medium-sized companies they go with this kind of solution there is the first option we can use a simple default route now the second option is we can have a default route that is one thing and also we can have some specific route this is another way of implementing is one or more implementation which we can do if you are running BGP now what I am going to do is I am going to have a default route from this side and both the sides I am going to have a default route that is just like a case at the same time I am also receiving some specific routes they stick route spins let's say I regularly access some of my servers on the internet there are some 10 servers or my company's service or anything I got some regular service maybe Yahoo Gmail or it can be any any other service now what I will do is I will try to only receive this network information into my BGP table which means in my BGP table I have the information of those 10 servers or networks but I am NOT going to maintain the complete internet routes for all end up so to reach those 10 routes or 10 networks I am going to receive the information and I can run BGP and I can say that 10 dot network and 20 tour networks should use the primary ISP or I can say they will use is p1 route in my LAN so in my line in mind in mind s I got four different networks and I can do some path manipulation that these four networks when they go to the reach this specific service or specific networks they should use is p1 and the remaining two networks they should use is PD so I'm going to do some path manipulation based on those specific routes and if I am trying to access any other networks other than this like maybe I am trying to access some normal Internet traffic or I'm trying to do something other than other than accessing this specific service they just go with a default route so in this scenario I'm getting a default route which means it is reducing the overhead on my router I am NOT going to install all the rocks at the same time I have some specific routes so that I can do path manipulation only for specific selected destinations or specific selected networks at the same time for the remaining networks I am going to use the default out what I have that's the second option now the third option is exchanging all the internet rocks now in the third option what we are going to do is we are not going to use any default route we are going to exchange everything from the source form which means on my is any router in - is connecting to both ISPs this is my ISP 1 and n 2 is P 2 I am receiving all the routes from the service folders all the entered routes from this service forum now I will do path manipulation for each and every Network any network I go I want to access on the internet or any any other s I'll do my own path manipulation so based on that path none relation it is going to do the major drawback with the third option is it's really going to be very hard on your routers like your routers really need very huge processing is required to maintain all the routes information to run the BGP and you need to have some high end devices so especially this is more appropriate for very big size companies or if you are continuously communicating especially high speeds I can say the service for does need to maintain each and every route information coming those things so if you're running a specific organization big cellphone ization we can go with a second option in case of small size companies we generally don't do use PC we simply go with a default route with the primary and secondary options so these are some of the three different types of implementations which we use the default route from the service for which is very easy on the routers Internet traffic is routed with the nearest PGP router so it's just good for it based on your ICP information or we can just hello for selection selection of some paths with others falling back to the default route and the third one is we are going to exchange all the routes which is very hard on the resources of the router but again it is going to get it the most direct path or the shortest path it is going to Gary I show that but depending upon the requirement it can go with any one of these options so we discussed two things here we try to understand the different ways of connecting to ISPs slicing a single home dual home connections which are more appropriate using a default or without BGP and if you are running a multi-homing or dual multi home environment then it's really recommended to go with BGP and we do some pass translations at the same time when you're connecting to BGP when you're running when you're exchanging routes through on the internet through ISP through service for then we can have a single default route coming from the service folder and we are not going to run the BGP he is just getting the default route from the service border or we can have some specific routes from the service border and some specific routes and then the remaining will automatically switch back to the default chart and we can have all the routes exchanged from the service forest so three different types of implementations so probably we will try to jump into our laps we do some basic conversations in our next video so these are some of the basic things we need to understand before we start getting into BGP configurations ah

Channel: Sikandar Shaik

Views: 111,782

Keywords: border gateway protocol (bgp), border gateway protocol explained, border gateway protocol in computer networks, border gateway protocol configuration, border gateway protocol definition, what is border gateway protocol, how border gateway protocol works, what is border gateway protocol in networking, MicroNugget, cbt nuggets, computer based training, cbt, BGP, Border Gateway Protocol, routing protocols, bgp training, What is BGP?, bgp

Id: U7OQQpRJYSE

Length: 17min 33sec (1053 seconds)

Published: Mon Feb 27 2017