Many of you may have heard by now, IOS 15 is the way of the future for IOS based devices. Cisco made their official End-of-Sale and End-of-Life Announcement for Cisco IOS Software Release 12.4. So, if you weren't planning on upgrading to IOS 15 ever, at least now you can know when you won't be able to call Cisco for help. The specific dates for EOL and EOS are detailed in the link above, but here's is a screen shot of the dates to save you a click:
What will I get when I upgrade to IOS 15?
Well, Cisco has a Q&A page that explains a lot of fluffy details as to why IOS 15 is better than IOS 12. The best I could gather from reading it is this is the direction Cisco is going and that Cisco knows best. Aside from 15 being 12 plus 3, key features are: version numbers are easier to figure out, licensing of advanced features is handled in a more controlled way with Universal Licensing, and to top it off Cisco promises that they'll be more consistent with feature releases. The image below is from Cisco's Q&A page and shows 12.4 feeding directly into 15:
What's so cool about Universal Licensing?
The main point of Cisco's approach to the Universal Licensing model is that a single image can be deployed for a platform and if you actually need to unlock some of the more advanced features, then you can pay for a feature package and apply a license to your already existing device and existing code to unlock those features. No code upgrade typically required (unless a bug fix is needed or a new feature is released).
The image below depicts the process flow of Universal Licensing. Basically, you have a single code image on the left with all the features baked in. If you buy a feature set license in the middle column, that gives you the features on the right column:
Here's a potentially real life example:
A large enterprise starts deploying universal IOS with a base license at all of their sites. Down the road, a new CIO decides the enterprise needs to move to IPv6 even though the network engineers and architect say they have plenty of IPv4 space and that some applications are not compatible with IPv6 yet. The new CIO knows better and puts his or her foot down. Instead of upgrading to IP Services feature set from IP Base, you simply license the feature for all of the devices that need to run the new protocol and then apply the license.
In theory at least, that is how it can work. You can learn more about the details of Cisco's license activation process here: IOS Software Activation Conceptual Overview.
How do I manage a bazillion Cisco devices running Universal Code and different feature packages?
If you have a lot of gear that is running on Universal code and you need to manage different feature-sets that have been licensed, Cisco License Manager is the answer. I've installed this and tried it out in a small environment. Even though they are up to version 3, it still has some rough edges and is a little challenging to get it dialed in. I'm surprised they didn't just include this as part of CiscoWorks LMS to give people yet another reason they have to buy CW. Perhaps it will be integrated into LMS in the future, but for now it is a stand alone application that sorta works.