I am working in a network design for a implementation in a customer, so far we have decided that the Core will be a pair of 4507R with SupV10Ge, and the access should be 4x 3750G-48 for one floor, and 3x 3750G-48 for the second floor (Stack is a customer requirement for the access layer)...
Total number of users would be less than 400. Is the 4507R ok for the core?!
Also I am stuck in deciding which switch to use in the distribution layer... I am thinking about the 3750-E, but I am not sure about that, can you help me out on this?
Dont use a separate distribution layer, have a collapsed access/distribution layer. Use a mix of 3750G and 3750-E switch in the stack and then design the solution.
For a stack of 4 3750's use, 2 3750-E and 2 3750G'. Place one 3750-E on the top of the stack and other at the bottom.Run 10G connection from the top and bottom 3750 to the 2 core chassis. Do the same on the other stack as well.
If you have users based on the floor plan and dont have to extend the vlans to both the floors then do the intervlan routing for the users on the respective floor stack and run L3 connection from Access to core switches.
Richard makes a very good point. If you are designing for one building only there is no problem with using a collapsed distribution/core design. Your 4507's should be okay in this scenario although you don't say what type of applications you will be running.
Having a separate core from the distribution is quite often seen in campus models where you have a number of buildings to interconnect. This doesn't mean you shouldn't use a separate core in your design but depending on the setup a collapsed core/distribution may be just as viable a solution.
Are you sure you need separate core and distribution layers?
I use 4510's for distribution and 3750's for user access. I'm just now adding 6504's for a core, because of connectivity and firewalling needed to other sites. For Internet Data Center, it's all 6509's for distribution and access.