The 3 Topics You Need To Know For Your CCNA R/S Exam

ccna r/s May 23, 2017

Studying for your CCNA R/S (200-125) exam? If so, a perusal of the exam topics list can be daunting. Clearly, you’re going to spend a significant amount of time getting at least a passing familiarity with the myriad of topics. However, your focus should not be spread evenly over all topics. Rather, there are some topics that need a disproportionately large amount of study.

That’s the focus of this blog post, identifying 3 of the topics likely to appear multiple times on your 200-125 exam. These topics won’t come as any surprise, but I hope this will be a reminder to expend that extra measure of effort when reviewing “the big 3.” Let’s check out the list:

1. IP Addressing

To be prepared for IP addressing questions on the CCNA R/S exam, you need several skills, including:

  • Knowing how to convert between dotted decimal notation (e.g. and slash notation (e.g. /24) for subnet masks.
  • Determining the number of useable IPv4 addresses in a subnet.
  • Determining the number of IPv4 subnets created by applying a specific subnet mask.
  • Determining the network to which a given IPv4 address belongs.
  • Identifying what subnets are created by applying a specific subnet mask to a classful network.
  • Knowing how to calculate the EUI-64 IPv6 address for a given MAC address.
  • Knowing the different types of IPv4 and IPv6 traffic flows.


This version of the CCNA R/S requires you to know how to configure, verify, and troubleshoot the OSPF interior gateway protocol (IGP) not just for IPv4, but also for IPv6. So, if you have access to practice routers (or router simulators or emulators), labbing up a few OSPF topologies would definitely be a good use of your time.


Similar to OSPF, you’ll want to know how to configure, verify, and troubleshoot EIGRP for both IPv4 and IPv6.

Of course, all of the above topics are covered in my CCNA R/S (200-125) Complete Video Course. However, I do have some freely available YouTube videos covering these and other Route/Switch topics available in a playlist. Just click HERE to access the playlist, and enjoy the videos! 

Kevin Wallace, CCIEx2 (R/S and Collaboration) #7945