This past week I took and passed the Cisco Certified Design Expert (CCDE) Practical Exam, making me CCDE #20130013, or CCDE #2013::13 in geek-speak.  Cisco doesn’t publish official stats on either the number of CCIE or CCDE certified people anymore, but per the unofficial stats of the CCIE/CCDE Hall Of Fame this makes me one of about 100 engineers globally that currently hold this certification.  Pretty neat, considering I thought being one of 7500 CCIEs was really cool back in 2001.

In this post I’m going to talk about my personal journey to obtaining the CCDE, details about the practical exam itself (within NDA of course), and some recommendations for engineers that are currently pursuing or thinking about pursuing CCDE.

The weekend before the practical exam, Petr Lapukhov - CCDE #2010::7 and I hosted a CCDE Open Study Session in Chicago, my hometown, just a few blocks away from where the practical exam was delivered.  This was the second time I hosted one of these sessions, and I personally think these sessions ended up being the difference between me passing and failing in this attempt – but more on this later.  Congratulations to Chance Whaley - CCDE #2013::9, and Rolf Schärer - CCDE #2013::12, who both attended the study session and then passed the practical exam as well.  Also a special thanks to Petr for taking time out of his busy schedule at Microsoft’s Bing search unit to come hang out with us.

This was my second attempt at the CCDE practical, having taken the CCDE beta written exam at Cisco Live 2008, followed by the original CCDE beta practical exam in October of 2008 in Chicago. I believe there were over 100 of us who took the beta, and it was pretty much an utter disaster for all but three of us.  It took about 6 months for us to get the result back, which was essentially a short note that said “Score: FAIL”.  All in all it was a great experience though, especially the after party that Cisco hosted at the Signature Room on the 95^th floor of the John Hancock Center, which was a great chance to get together with other high-level engineers and complain about how we all failed the exam.  Also thanks to the new CCIE Tracker site I was actually able to finally see my score on the original CCDE beta practical, which turned out to be a measly 36%.

This past attempt was much better than the original beta, not only since I actually passed this time, but since Cisco has made significant improvements in the both testing engine and just the format of the exam in general.  Like any of the CCIE tracks, the CCDE certification is made up of two parts - a qualification written exam, and an 8-hour practical exam.  The CCIE and CCDE written exams are very similar in format, the same as any other Cisco written exam such as CCNA or CCNP.  The major difference though is in the practical exam.

In a CCIE lab exam, candidates are given 8-hours to solve troubleshooting and configuration scenarios on live equipment, such as routers, switches, firewalls, etc.  In CCDE however, the 8-hour practical exam uses a testing engine similar in some aspects to other Cisco written exams, but is much more advanced in many ways.  Not only are there multiple choice, multiple answer, and drag-and-drop type questions, but there are also questions that require the candidate to analyze network diagrams, suggest the addition/removal of network devices, and suggest the addition/removal of configuration features, all while keeping the ever expanding requirements of the customer in mind of whose network you are currently working on design changes for.

Specifically, the CCDE practical exam is broken down into two sections of two scenarios each, for a total of four scenarios.  For each section candidates are allotted 4 hours, and between sections there is a mandatory lunch break.  In our case I think we took about 30 minutes or so for lunch.  For me personally timing wasn’t that big of an issue, as I spent just over an hour on each scenario, finishing the first three before lunch and then spending about an hour after lunch on the final scenario; all in all I think I spent about 5 hours on the exam give or take.  What’s strange though is that instead of a single block of 8 hours, you get two blocks of 4 hours.

Even if you finish the first section early, that time doesn’t carry over into the next section.   The reason this could be an issue is that all scenarios aren’t created equal.    During the brief chat between candidates at lunch break, it was apparent that not everyone’s exam delivery was the same.  While many of us likely got some of the same scenarios, they weren’t all delivered in the same order.  The end result is that you could get a delivery where the scenarios of one section take you much longer to complete than the other.  For example you could finish the first section in 2 hours, and then run into trouble with the next section and have the clock run out at 4 hours.  If it was up to me I would say there should be a single block of 8 hours that you can spend between scenarios as you wish, but unfortunately I’m not on the CCDE exam delivery team.

Another big improvement to the CCDE practical is that the grading is 100% automated and immediate, just like any other Cisco written exam.  For me personally I’ve had the experience of having to wait 6 months for results in the original beta, and having to wait 60 seconds for results in the 2.0 format.  By far having to wait only 60 seconds for results is better.

As I mentioned, the format of the questions of the CCDE practical go above and beyond other normal written exams.  You can get a better idea of what I mean by this by checking out the CCDE Practical Exam Demo on the Cisco Learning Network.  Don’t worry about the answers or your score on the demo too much, as our study group scored about a 23% collectively on it.  No, I don’t mean 23% as an average, I mean all 30 of us working collectively on it and voting on the answers we scored a 23% :)

The key differences between other written exams and the CCDE practical is that you are first presented with an overview of the business of whose network you are working with, and some of the high level information on what their current design is and what their future design goals are.  For example you may be presented with ACME Corp., a multi-national enterprise that manufactures widgets.  ACME currently has 100 remote sales offices, 3 manufacturing facilities, 2 data centers, and the corporate HQ that are connected together with a combination of legacy Frame Relay T1s and analog dial-up VPDN.  ACME is planning on adding 200 new sales offices over the next 18 months due to an acquisition, and must integrate with the acquired manufacturing and data center locations as well as the sales offices.

Based on this the exam might ask you questions on what your recommendations are for ACME to expand the design, what are the possible technologies that fit the technical specs, the budget requirements, the security requirements, the compliance requirements, etc.  What is really interesting about the exam though is that there are multiple possible branches you can go down.  For example if the question asks you what you would recommend ACME do to migrate off of the legacy Frame Relay network, and you choose MPLS L2VPN with VPLS, the exam may follow this up with questions such as – What are the advantages of using MPLS L2VPN VPLS vs. MPLS L3VPN?  What are the disadvantages of using VPLS vs. using DMVPN for this solution? Etc.  At times it’s hard to tell whether your answer was correct, or whether your answer was wrong and the testing engine is simply leading you down the wrong branch.  Eventually however the branching of the exam reaches a limit and it will correct you back to the branch that they wanted.  For example if you chose VPLS and they wanted MPLS L3VPN, you may eventually hit a dead-end and see the next question read “ACME Corp. has decided to go with MPLS L3VPN as the migration solution off of legacy Frame Relay…”.  All in all the testing engine itself, along with the content, is much better executed than the original beta exam in my opinion.

As for the exam content, the major focus is layer 2 switching and layer 3 routing design.  While you don’t necessarily need to be an expert in the day-to-day implementation or support of these technologies, you do need to have an expert level understanding of what the technological advantages and limits are of choosing one design over another, as well as the impact on day-to-day support and maintainability, along with the financial implications of your design choices are, i.e CAPEX vs. OPEX.  Specifically the exam has a large focus on layer 2 technologies such as Frame Relay, ATM, and Ethernet, layer 3 routing technologies such as OSPF, EIGRP, and IS-IS IGPs, as well as BGP, tunneling techniques such as GRE, IPsec, L2TPv3, MPLS L2VPN & L3VPN, DMVPN, and other miscellaneous topics such as security filtering, QoS, and Multicast.  While these may seem very broad and vague, it is simply the nature of the beast.  If you are an enterprise engineer that has spent the last 20 years working on Ethernet, OSPF, and BGP but don’t really know how IS-IS works… you will very likely fail the CCDE.  If you are a Service Provider engineer who’s an expert in core IS-IS and MPLS design but doesn’t really know where EIGRP and DMVPN fit together… you will very likely fail the CCDE.

This is one of the reasons that Cisco’s CCDE Practical Reading Booklist is so long.  Do you really need to read all of these books?  No, not really.  Do you really need to know all the topics that these books cover?  Yes, definitely.  Petr Lapukhov also posted a CCDE Practical Exam Recommended Reading list a while back on the INE blog, and again while it is very intimidating, there’s no shortcut in understanding how these technologies really work and impact network design.  This is also one of the reasons that INE does’t really offer CCDE “classes”, as it’s not really a skill that you can teach per-se as compared to CCNA or even CCIE R&S, etc.  Instead, you have to sit down and spend the time to learn the technologies, which often in most cases takes years of expertise to master due to the sheer breadth and depth of content.

For me personally I’ve now been a CCIE for over 11 years, and been in IT for over 16 years.  Although I’ve read many, if not all, of the texts on these lists, one of the shortcomings I found in myself was being able to step out of my normal conceptions and look at design options from a different more objective angle.  For many engineers this is very difficult to do, as per their experience they may be more comfortable with OSPF over IS-IS, or flat out refuse to use EIGRP in any design case, etc.  This is where the study sessions we ran really helped.

In the study session essentially what we did was read through CCDE level scenarios that Petr had previously written, and then as a group discussed the possible solutions, advantages, disadvantages, etc. on a step-by-step basis.  In the three days of this past session we barely finished going through two scenarios.  Essentially what should have taken less than 4 hours in the practical exam we spent over 20 hours discussing in class.  Many of the attendees weren’t even planning on taking the CCDE practical, but instead just attended to participate in and listen to the discussion amongst other engineers.

Based on the feedback of this past study session, along with the previous one that I ran in London in November 2012, INE is going to continue to run them in tandem with the CCDE practical schedule.  The upcoming dates for the practical this year are May 30^th 2013, August 27^th 2013, and November 22^nd 2013.  The locations for the study sessions are yet to be determined.  If you are interested in attending, please let us know below as to which location you would be interested in, either Chicago, San Jose, or RTP in the USA, or London UK.

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Thanks again for those who took the time to come out to the CCDE study session, and I hope to see you in a future one!

Brian McGahan - CCIE #8593 (R&S/SP/Security) & CCDE #2013::13