Congratulations go out to the newly minted Cisco Certified Design Experts that passed the Practical Exam after attending INE's CCDE Bootcamp with me in Chicago last week! So far I know of at least 9 students from this past week's class and previous ones that passed the practical this time around. Here's what some of them had to say:

I had accomplished 2 CCIE's and was ready for the CCDE. I took the CCDE v1 test a couple of years ago and failed miserably. I came to the INE CCDE boot camp with really no expectations. I didn't only learn some technical details through the boot camp, I learned the mental strategies needed to get through this test. Thanks, INE!!

Rob Gonzalez, CCDE #20130059

Brian's approach in how to tackle the exam question were invaluable. I was able to successfully navigate several difficult questions there on my first attempt. Thanks to Brian and his insight I was able to pass.

Travis Jones, CCDE #20130060

Hi Brian,

Just wanted to drop you a note that I passed the exam today. Still in shock, but it’s starting to sink in. Thanks for a great session this week. I’ll highly recommend it!

Dave Fusik, CCDE #20130070

I passed the CCDE in Chicago after attending the 3 day INE CCDE Bootcamp with Brian McGahan. The room was full of very intelligent and experienced individuals who started discussions that helped solidify my knowledge in the topics tested on the exam. Thank you once again INE!

Dana Yanch, CCDE #20130071

As it seems that the interest in the CCDE track is continuing to grow, INE is going to continue to offer our study sessions which follow along with Cisco's schedule for the Practical Exam. The next Practical Exam is scheduled for Thursday February 20th 2014, so expect our next session to likely run Monday - Wednesday that same week in Chicago. However since Cisco is now offering the CCDE Practical Exam at all Pearson Professional Center locations, there's a possibility that we may be moving our next study session to an online format.

If you're interested in attending one of INE's CCDE Bootcamps in the future, let me know via comments below if you prefer it in an online format or a live onsite format. The advantage of course of running it online is that you can attend from anywhere, but at the expense of the live class discussion that happens in an onsite class.

Also don't forget to check out our CCDE Practical Recommended Reading List, as the topic scope for the exam is immense to say the least.

Congrats again to the newest CCDEs of 2013!


Starting next year Cisco will be offering the CCDE Practical Exam at many more locations beyond San Jose, Chicago, London, etc., and registration for the practical will be open up to the day before the exam. Another nice change is that candidates can take lunch break on their own time after finishing the second scenario in the exam, where previously they were required to wait until the set lunchtime was finished before continuing on with section 3. The specific announcement from Cisco is below, along with the link to the CCDE page which outlines exactly where the new locations will be.

Starting with the February 20, 2014 exam administration, the CCDE practical exam will be available at all Pearson Professional Centers (PPCs) worldwide. The ability to conveniently take the CCDE practical exam at a local PPC testing center eliminates the stress and expense of traveling to a remote exam location.

The overall exam administration experience has improved giving you more flexibility in the following areas:

Choosing your exam location:

  • The number of locations where this exam can be administered will  increase from 8 to 275

Registering  for the exam:

  • Registration will close one day before the test date
  • However, candidates are encouraged to register at least 45 days in  advance for most locations to guarantee PPC sites will be open for the required  nine hours to administer the CCDE practical exam

Breaking  for lunch:

  • Candidates can only take a lunch break after they finish section 2
  • Candidates are no longer required to take a lunch break simultaneously

There are no changes to the exam content, scoring methodology, or modular testing approach. See the FAQs for more detail


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 95th 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 30th 2013, August 27th 2013, and November 22nd 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.

[poll id="51"]

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



INE would like to send a big congratulations out to our very own Brian McGahan, who just moments ago took and passed the Cisco CCDE exam! Numbers are still forthcoming, but this being the first exam given in 2013, may well be CCDE #2013::1. Brian will be writing a more in-depth blog post here, outlining some of the more fundamental aspects related to reading and studying for the exam, but in the interim, we just wanted to say CONGRATULATIONS!!


Update: There will be another session running May 27th - May 29th, 2013 in Chicago. Registration info can be found here.

I will be holding a CCDE Open Study Session in Chicago, IL from Saturday Feb 16th through Monday Feb 18th. The CCDE Practical Exam in Chicago is the following day, Feb 19th. This is similar to the one that I held in London last November prior to the previous practical exam, but this time I didn't miss the cutoff for scheduling the practical so I will actually be taking the CCDE exam on the 19th with others who are attending the session ;)

This isn't a "bootcamp" per-se but more of an open discussion or "groupstudy" if you will. We will be working through scenarios written by myself, Brian Dennis, and Petr Lapukhov (CCDE 2010::7) for the days leading up to the CCDE Practical Exam.

There is no cost to attend the session. Even if you aren’t going to take the CCDE but are interested in getting a chance to discuss real world networking with other senior engineers then you should attend. We had a great time in London as nearly everyone was at least a CCIE and many double/triple CCIEs which allowed for interesting discussions on the scenarios and technologies in general. Candidates who are actually taking the practical in Chicago will be given priority though as seating is limited.

If you would like to attend please send an email to Jeremy Brown (INE’s Class Coordinator) at to reserve a seat.

The location of class is yet to be determined, but it will be in downtown Chicago (Chicago Loop) close to where the CCDE practical exam will be at the Pearson Professional Center.


I'll be in London the week of November 19th for an Service Provider Bootcamp that I'm teaching until Friday the 23rd. I'm going to keep the facility and do a CCDE Open Study session like the one I did in San Jose a couple weeks ago. I'll be able to allow up to 25 people attend and of course it's free of charge. We'll go over one CCDE scenario per day for the 3 days prior to the exam which is being held in London on the 27th of November.

Even if you aren't going to take the CCDE but are interested in getting a chance to discuss real world networking with other senior engineers then you should attend. We had a great time in San Jose as nearly everyone was at least a CCIE and many double/triple CCIEs which allowed for interesting discussions on the scenarios and technologies in general.

I'll try to keep doing these sessions a few times a year and keeping them free of charge in various locations to help promote the CCDE program.

Our London location for the CCDE Open Study Session will be the Rydges Hotel in Kensington. This is the same location as my R&S and SP London bootcamps.

Rydges Kensington
61 Gloucester Rd, London, Greater London
SW7 4PE, United Kingdom

Google Map Link

The Rydges Hotel is a little on the pricey side as it's in a really nice area but if you want to stay there Jeremy Brown our Bootcamp Coordinator can get you a discounted INE rate. Also you'll be right down the street from the Natural History Museum, Victoria and Albert Museum and Harrods.

To sign up for the session, email Jeremy Brown and he'll reserve your seat.

I'll post a CCDE recommended reading list and I'm trying to get a CCDE simulation released over the next couple months. I have the content developed and just waiting for the testing engine to be finalized.

Lastly during the last session in San Jose we "cracked" the CCDE demo ( to get a 100% score. If you haven't taken the new demo try it out and see what score you get. Then next week I'll post the answers to the demo here on the blog.


I will be holding a CCDE Open Study Session in San Jose, CA starting Monday July 30th and wrapping up Thursday August 2nd. The CCDE Practical Exam in San Jose is the following day August 3rd. This session is becoming held the Tech Mart Meeting Center in Santa Clara which is just down the street from Cisco's main campus and the Pearson Vue Testing center.

There is no cost to attend the session. Drinks, snacks, lunch, and internet will be provided free of charge. We will work through scenarios written by myself and Petr Lapukhov (CCDE 2010::7) for the four days leading up to the CCDE Practical Exam.

If you would like to attend please send an email to Jeremy Brown (INE's Class Coordinator) at to reserve a seat.


Just ahead of our brand new CCNA Voice live online bootcamp beginning this Monday, I thought it might be nice to provide an easy-to-follow graphic for those starting out in Voice (or on any other Cisco networking track). This graphic was from last year, but remains quite easy to follow for each and every Cisco track.

Be sure you have a high resolution set if you wish to see the entire thing, otherwise scrolling may be necessary.

Click here for the Cisco Career Certification Path poster


The CCDE bootcamp is coming shortly on May 1st, and we would like to provide some information to those of you who have already registered for the class or considering to join us. The class will go for five days and finish right before the CCDE practical exam in Chicago. The class is interactive for the most part - instructor will present you documents, diagrams, slides and questions on board and then the whole class will go through the solutions in live mode, discussing various options and correct answers. The class is centered around three major "platforms": generic "large-scale" network topologies that are used to construct various network design cases. There are three main platforms presented in the class:

  • Internet Service Provider. A fictitious ISP that provides VPN and Internet services to enterprises in addition to wholesale Internet services. Generic two-layer network, featuring a mix of interconnection technologies and using ISIS/BGP for routing. This platform is mainly used to work with scenarios relating to transit traffic services.
  • Application Service Provider. A company that has its own wide-area network interconnecting data-centers and points-of-presence. The company provides server application services - e.g. a virtual call-center, online support desk etc to multiple customers. Customers connect either directly or tunneling over Internet. This platform is used to demonstrate issues arising in networks that provide centralized services to different customers. This network uses OSPF and BGP for routing, traffic flows are mainly considered to be "client-server" flows between different networks.
  • Large Enterprise Network. Presents a generic enterprise network with diverse set of offices and private WAN network. The network services just one company, but has to support a large variety of application and different connection types. Traffic flows are mainly contained to one network but there are multiple "concentration" points. The network uses EIGRP for routing.

Every platform is used to construct 5 different scenarios, featuring from 15 to 20 different questions each. Answering each question requires analyzing the network baseline and additional information presented through the course of the class and selecting the optimal answer. Similar to the actual exam, the scenarios will have one the the following logical structures:

  • Merge two networks or spin off a new network.
  • Add a service or application - e.g. deploy L3 VPNs or add VoIP.
  • Scale the network - accommodate technologies to network growth, e.g. IGP/BGP/MPLS scaling.
  • Replace a technology - e.g. replace routing protocol or link type with another one.

You will be required to do a "fresh" design or fix a faulty/suboptimal scenario and propose a better solution. For example, you may be asked to fix a network that has new application deployed that is not working as required. The class will focus on live discussion of design problems as well as strategy tips for passing the CCDE practical exam. One again, students are assumed to have knowledge equivalent in scope to CCIE Written exam blueprint. And lastly, the following is link to a sample CCDE scenario - baseline and questions in the format they are going to be presented during the class.


Continuing my review of titles from Petr’s excellent CCDE reading list for his upcoming LIVE and ONLINE CCDE Bootcamps, here are further notes to keep in mind regarding EIGRP.

About the Protocol

  • The algorithm used for this advanced Distance Vector protocol is the Diffusing Update Algorithm.
  • As we discussed at length in this post, the metric is based upon Bandwidth and Delay values.
  • For updates, EIGRP uses Update and Query packets that are sent to a multicast address.
  • Split horizon and DUAL form the basis of loop prevention for EIGRP.
  • EIGRP is a classless routing protocol that is capable of Variable Length Subnet Masking.
  • Automatic summarization is on by default, but summarization and filtering can be accomplished anywhere inside the network.

Neighbor Adjacencies

EIGRP forms "neighbor relationships" as a key part of its operation. Hello packets are used to help maintain the relationship. A hold time dictates the assumption that a neighbor is no longer accessible and causes the removal of topology information learned from that neighbor. This hold timer value is reset when any packet is received from the neighbor, not just a Hello packet.

EIGRP uses the network type in order to dictate default Hello and Hold Time values:

  • For all point-to-point types - the default Hello is 5 seconds and the default Hold is 15
  • For all links with a bandwidth over 1 MB - the default is also 5 and 15 seconds respectively
  • For all multi-point links with a bandwidth less than 1 MB - the default Hello is 60 seconds and the default Hold is 180 seconds

Interestingly, these values are carried in the Hello packets themselves and do not need to match in order for an adjacency to form (unlike OSPF).

Reliable Transport

By default, EIGRP sends updates and other information to multicast and the associated multicast MAC address of 01-00-5E-00-00-0A.

For multicast packets that need to be reliably delivered, EIGRP waits until a RTO (retransmission timeout) before beginning a recovery action. This RTO value is based off of the SRTT (smooth round-trip time) for the neighbor. These values can be seen in the show ip eigrp neighbor command.

If the router sends out a reliable packet and does not receive an Acknowledgement from a neighbor, the router informs that neighbor to no longer listen to multicast until it is told to once again. The local router then begins unicasting the update information. Once the router begins unicasting, it will try for 16 times or the expiration of the Hold timer, whichever is greater. It will then reset the neighbor and declare a Retransmission Limit Exceeded error.

Note that not all EIGRP packets follow this reliable routine - just Updates and Queries. Hellos and acknowledgements are examples of packets that are not sent reliably.

Subscribe to INE Blog Updates

New Blog Posts!