In a typical architecture, where you would have front-end & bankend servers i.e. divided into DMZ1, DMZ2, INSIDE etc, single/dual Cat 6500 chassis is used with multiple vlans defined. And this is considered a common design.
However, when it comes down to separate switches, it is widely seen that switches are placed in every segment i.e. DMZ switch, INSIDE switch etc. Why is it so ? Why can't a single switch be divided into multiple vlans hosting all the segments like DMZ, INSIDE etc similar to Cat6500.