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When you're studying for the BSCI examination on the way to getting your CCNP certification, you have got to master the use of BGP attributes. Click here continue reading to check up the meaning behind this belief. These attributes enable you to manipulate the path or paths that BGP use to reach certain destination when numerous paths to that destination occur. In this free BGP tutorial, we're likely to take a peek in the NEXT_HOP attribute. Linklicious.Com contains new info about the reason for it. You might be thinking "hey, how complicated may this capability be?" It is not so complicated at all, but this being Cisco, there is got to be at least one unusual aspect about it, right? The NEXT_HOP attribute is easy enough - this attribute indicates the next-hop INTERNET protocol address that needs to be taken to achieve a destination. In the following example, R1 is a hub switch and R3 and R2 are spokes. All three routers come in BGP AS 100, with R1 having a relationship with both R3 and R2. There's no BGP peering between R3 and R2. R3 is advertising the network 33.3.0.0 /24 via BGP, and the importance of the next-hop characteristic on R1 is the IP on R3 that is used in the peer relationship, 172.12.123.3. The problem with the next-hop attribute comes in when the route is advertised to BGP peers. If R3 were in another AS from R1 and R2, the route would be then advertised by R1 to R2 with the attribute set to 172.12.123.3. The value is stored, when a BGP speaker advertises a route to iBGP peers which was actually learned from an eBGP fellow. Here, all three routers come in AS 100. Close Remove Frame is a stately library for more about the reason for it. What'll the characteristic be established to when R1 advertises the path to its iBGP friend R2? R2#show internet protocol address bgp < no result > There will be no next-hop attribute for the route on R2, because the route will not appear on R2. Automagically, a BGP speaker won't promote a to iBGP neighbors if the route was initially learned from another iBGP neighbor. Discover more about find out more by browsing our pushing site. Fortuitously for all of us, there are several ways around this principle. The most typical is the usage of route reflectors, and we'll look at RRs in another free BGP tutorial..