In this video, Bill Ferguson demonstrates a subnetting error on a connection between routers. Learn how to resolve issues like these by subnetting in your head.
- [Instructor] Okay, so to prove all of this,…I've set up a simple network topology.…This one happens to be on Boson NetSim,…but it could be on any simulator,…or, obviously, on real equipment as well.…The main point is that I have two routers…that are sitting right next to each other…and have point-to-point connections to each other.…And I have the IP addressing that we used in our demo.…I'll show you that by, on Router1,…I'm going to type, sh ip int e0/0.…
And, if you take a look at the top of the screen,…right below where the routers are,…you'll see that the internet address is 172.16.5.1/21,…just like our example.…Also, I'm going to go to Router2…and type, sh ip int e0/0…and notice that the IP address there is 172.16.9.1/21,…just like in our example.…
Now, these two routers are right next to each other.…Their interfaces are point-to-point.…And they're electrically connected to each other.…What do I mean by electrically connected to each other?…Well, if on Router2, I were to type sh cdp nei…he says, "Well I see Router1."…
Discover how IP addresses are constructed and how to understand them better by relating them to a picture rather than converting binary numbers or memorizing charts. Learn the benefits that subnetting in your head provides in every aspect of IT networking, including routing protocols, access control lists, and network address translation. Then walk through Bill's four-step method, which leverages the rules that were used to create the original classful IP addressing schemes. Using this method, students can learn to "see" the IP addresses for each subnet. Watch the technique in action, and then practice what you've learned using the audio guides in chapter five, which provide auditory cues as you subnet in your head.
- The benefits of subnetting
- Class A, B, and C IP addressing
- The four-step subnetting method
- Troubleshooting IP topologies and IP host address ranges
- Audio cues for the four-step method