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New Member

CatOS and IOS

Why did Cisco decide to have two different types of OS's? (CATOS and IOS) Are then any beinfits from one to the other?

Do both OS's use Cisco's proprietry Spanning Tree Protocals, PVST and MISTP?

Regards and thanks.



Re: CatOS and IOS

Probably it is more correct to say that it just happened to them because Cisco wanted to grow. To realize a share of the switching market they aquired other companies with products that Cisco expected to be successfull. Catalyst switches were one of these.

Then Cisco had to sell them asap to make their aquisition pay off. But these non-cisco products were never designed to run under the IOS and were therefore incorporated in the Cisco-product range with little more changes than a suitable black/blue painting and the Cisco logo.

The long term goal is (or has been) to incorporate all functionality on all devices in the IOS. You can see that Cisco has made considerable progress in this effort but I would be surprised if the CatOS was to disappear within the next 3 years.

The same approach is chosen for other non-cisco products like the PIX firewall and the VPN concentrators.



New Member

Re: CatOS and IOS

Thanks for that Leo, very informative.

Last question is… Do both OS's, CATOS and IOS use Cisco's proprietary Spanning Tree Protocols, PVST and MISTP?

Or do they work differently?

Just wanted to know if there both nice and compatible.

Cisco Employee

Re: CatOS and IOS

Hi Michael,

Yes, both CatOS and IOS support PVST and MISTP. However, while PVST is Cisco proprietary, MISTP is an IEEE standard (802.1s).



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New Member

Re: CatOS and IOS

Many thanks.

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