Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

IOS name versus Feature Set

Hi Everyone,

I would like to know if anyone knows how can we identify, using only the IOS name (i.e using only the letter of its name, for example, s, is-mz, js, k, etc) that those IOS is set to use an determined Feature Set?.

For example, the following IOS: "c2600-JS-MZ.122-32.bin" is set to "Enterprise Plus" feature set. From this, we know that the letters "JS-MZ" stands the Enterprise Plus feature set.

Another example, using the same platform, router 2600, the following IOS "c2600-IS-MZ.122-30.bin" is set to IP Plus. From this, we know that the letters "IS-MZ" stands "IP Plus" feature set.

Thanks everyone in advance!!!



New Member

Re: IOS name versus Feature Set

If I understand you it sounds like you've almost answered your own question.

I = IP

IS = IP Plus

JS = Enterprise Plus

SP = Service Provider

The MZ: M is for the memory location and the Z is the compression format.

Here is a doc that breaks down how to interpret an IOS name.

This is also helpful:

New Member

Re: IOS name versus Feature Set

Hi James,

OK. Thanks for your notes.

Best Regards,


Hall of Fame Super Silver

Re: IOS name versus Feature Set

Hello Marcelo,

there was a old link that could be accessed with a qualified access on CCO

I've found the following:

the codes change with the main release.

New IOS images have the name containing the feature set

You can use the feature navigator and make a search by image name to decode

some info about old name structure:

Image Naming Conventions

You can identify the platform, features, and image location by the name of the image. The naming convention is platform-featureset-type for images.

The platform variable indicates which platforms can use this image. Examples of platform variables include rsp (Cisco 7000 series with RSP7000 and Cisco 7500 series), c1600 (Cisco 1600 series), and c1005 (Cisco 1005).

The featureset variable identifies the feature package that the image contains. Cisco IOS software comes in feature sets tailored to suit certain operating environments, or customized for certain Cisco hardware platforms.

The type variable is a code indicating the characteristics of the image:

•f-The image runs from flash memory.

•m-The image runs from RAM.

•r-The image runs from ROM.

•l-The image is relocatable.

•z-The image is zip compressed.

•x-The image is mzip compressed.

in your case JS is enterprise plus MZ says how the image is executed.

the codes combines together to provide more info like k9 means 3DES o3 IOS firewall and so on.

Hope to help