CCIE Pursuit Blog

January 17, 2008

Cisco’s Official Response Concerning Dynamips

Filed under: Cisco,Cisco Certification,Dynamips,Home Lab,IOS — cciepursuit @ 3:40 pm
Tags: , , , ,

I was reading this post at Brad Reese’s blog about installing Dynamips.  It has a link to the Internetwork Expert Dynamips COD.  It also has a picture of one of the Brians (McGahan – at Networkers?). 

The bit that caught my interest was this post concerning the official Cisco (non)response concerning Dynamips.  It seems that CertGuard believes that Dynamips may be in violation of Cisco’s IOS copyright and licensing agreement.  Cisco’s response:

As a matter of policy, Cisco will not comment on a specific customer or organization’s use of Cisco software.

That said, it is accurate that according to Cisco’s standard software licensing terms, users may only run Cisco software on the Cisco hardware for which the user pays the appropriate fees.

We have also heard from customers that emulation/simulation tools are of value to them and we are exploring different ways on how to continue to help customers best design and test network configurations prior to deployment of their networks.

Dynamips does not include IOS images so I don’t think that they really need to worry about Cisco turning the Eye of Sauron on them.  I don’t think that anyone is looking to throw Dynamips on a PC and using that to replace the 2800 routers in their network.  For Cisco, Dynamips is a boon.  It is allowing more certification candidates to get hands-on (emulated) experience with their products.  The only (extremely slight) downside to their business is the (very few) certification candidates that will be using Dynamips instead of buying new Cisco gear.  Most of that market was being served by eBay and used equipment vendors anyway.  Plus, Dynamips is absolutely free so there’s no one getting rich on the backs of Cisco.  That said, it does look like Dynamips users – by obtaining and running Cisco IOS images in Dynamips – ARE in violation of software licensing agreement.  But, considering the effect of this practice on Cisco, I don’t expect Cisco to do anything.

In the end, CertGuard’s point is interesting (and likely true) but I can’t see any harm that Dynamips does to Cisco, while I can see plenty of upside for Cisco from Dynamips.


While Cisco is probably not affected by Dynamips “market”, vendors who currently offer simulators for the Cisco certification markets ARE going to be affected. 



  1. For a more comprehensive history on how the Dynamips conversation got started, please read this (3 page)thread:

    Honestly, I hope Cisco works something out with Mr. Fillot. I would like to see Dynamips on the market just as much as anyone that it benefits. Because of the nature of CertGuard, however, we cannot support it in it’s current capacity.

    Thanks for the blog.

    Best Regards,

    Robert Williams
    CertGuard, Inc.

    Comment by Robert Williams — January 17, 2008 @ 6:13 pm | Reply

  2. Dynamips is not going to go anywhere or else Cisco would have crushed it long ago. I once bought a CCNP simulator from a vendor and it was terrible so I don’t shed a tear for them.

    I thought the Cisco IOS was going to go open source soon anyhow ?

    Comment by Carl Yost Jr — January 17, 2008 @ 8:51 pm | Reply

  3. Why would Certguard be concerned about this anyhow?

    Comment by Carl Yost Jr — January 17, 2008 @ 8:59 pm | Reply

  4. Also Cisco has no reason to fear people using Dynamips on PC’s to replace their routers.

    1. People already do this using Linux Routers on PC’s.

    2. A real engineer would never do this anyhow, why not ? Flash file system is king and always will be. True routers don’t have the hardware failure rate of PC’s. I know the last thing I want to worry about is a hard drive shutting down our T3 while I am on vacation…

    Comment by Carl Yost Jr — January 17, 2008 @ 9:23 pm | Reply

  5. @Robert

    I agree with you about Cisco and Christophe Fillot working something out. Cisco’s response seems to indicate that they are working in that direction:

    “We have also heard from customers that emulation/simulation tools are of value to them and we are exploring different ways on how to continue to help customers best design and test network configurations prior to deployment of their networks.”

    I read through your forum post as well as the CertCities forum post that I put in my blog posting. I agree that it is a clear breach of the EULA to use Cisco IOS with Dynamips. I am not arguing that point, nor do I think that CertGuard is the “bad guy” in this situation. I do echo Carl’s position in that I don’t know why CertGuard would be concerned about this situation. I don’t see how the availability of a Cisco emulator would damage Cisco’s certification program. In fact, I think that it enhances it.

    I do have to say that I am a little interested to see Boson employees active in both threads. Boson IS affected directly by Dynamips because they offer simulation products that will most likely lose sales due to the popularity of Dynamips:

    Boson NetSim for CCNA 7.0

    Boson NetSim for CCNP 7.0

    Anyhoo…I think that Cisco is either going to co-opt Dynamips (or develop their own emulator) or continue to ignore it. I don’t see any upside to Cisco following up on the IOS agreement breach.

    Comment by cciepursuit — January 18, 2008 @ 12:31 pm | Reply

  6. I was thinking Microsoft/SCO vs Linux when I seen BosonMichael in each and every thread. There is the motivation to care. If you go to the Certcities boards BosonMichael and Headhunter are pretty much blasting every Dynamips user and telling them they are going to be sued.

    I honestly could see Cisco coming out with a watered down IOS strictly for Dynmaips.

    Comment by Carl Yost Jr — January 18, 2008 @ 2:36 pm | Reply

  7. As a Cisco employee, I can tell you Cisco is a very reasonable, open minded, and fair company – almost too much so in my opinion. If Cisco can let large silicon valley competitors copy and sell Cisco intellectual property like DHCP Snooping and IP ARP Inspection without filing suit, I highly doubt Cisco would litigate a kid in his basement writing some code just trying help people learn more about IOS. Cisco has a long history of always “taking the high road” in situations like this.

    Comment by Brad Hedlund — January 18, 2008 @ 10:06 pm | Reply

  8. @cciepursuit
    Thanks for the comments. I agree that Dynamips has nothing to do with IT Certifications and that I shouldn’t have involved myself, but I felt a minor obligation to help fellow trainers that were concerned about its existence. Basically, we were just trying to get to the bottom of an issue that seemed to be unanwered up to that point.

    @Brad Hedlund
    I’m sure if you would do a little research on Christophe Fillot, you’ll find that he is much more than ‘a kid in his basement writing code’.

    Comment by Robert Williams — January 24, 2008 @ 5:00 pm | Reply

  9. ‘Kid in his basement writing code’ was obviously a rhetorical figure of speech. When you compare a individual person like Christophe Fillot to a large comapny like HP Procurve, the ‘kid in basement’ is somewhat fitting. I didn’t think anybody would take it that literally … hehe 🙂

    Comment by Brad Hedlund — February 7, 2008 @ 4:31 pm | Reply

  10. No doubt Dynamips is a boon to the CCIE-to-be community. I wonder why Certguard so much concern about the others using Dynamips? Downside of Dynamips would be it would degrade the CCIE in such a way that you could see CCIEes without even seeing a cisco router or switch or without having any networking experience! As I read about a 18 year old chap who passed the CCIE a few months back!

    Comment by tyousuf — August 3, 2008 @ 12:28 pm | Reply

  11. “CCIEs without having any networking experience”????seems to be impossible.

    Comment by Darkkmaul — October 24, 2008 @ 2:30 pm | Reply

  12. […] Cisco software on the Cisco hardware for which the user pays the appropriate fees”. This is discussed a little more in depth in this posting, but basically you are breaking your Cisco IOS terms of use by running IOS on Dynamips.  That […]

    Pingback by Dynamips for CCIE - Part 1 - What is Dynamips? « CCIE Pursuit Blog — January 5, 2009 @ 12:06 pm | Reply

RSS feed for comments on this post. TrackBack URI

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

Blog at

%d bloggers like this: