3750 Series Switches Question

To my knowledge, none of Cisco's 1u boxes are 'upgradeable'. The only boxes that can take module upgrades or replacements are the chassis- based products like the 4500, 6500, etc. As for POE, its not used unless a device is actually pulling current, so there is no additional cost, except for the cost of the device itself. POE is generally used for VOIP or other powered devices, we had many POE devices in a retail organization I used to work for.

A 24-port upgrade to a 3750-24 would be another of them, and you can cable them together. If you have the 3750-E, you have portwise stacking cabling you can do. If not the E model, then just ether-channel some of the ports together.

Or you buy the 48-port version and redeploy or sell off the 24-port version.

These are fairly "low-end" switches and aren't modular like some of the bigger ones are.

Cisco has a zillion resellers, you can buy from any number of them. Cisco sales itself probably prefers to go only after accounts that buy alot (ie. probably > $100k). You can pretty much get any cisco kit from any reseller.

Yes, its called a power injector AIR-PWRINJ3=. It goes inline between your existing switch, and the unit to be powered over ethernet.

Other manufactorers (ie. d-sine) make standard 802.11af (and some even pre-standard cisco) midspan power injectors in 1 to 16 ports or so if you just a few PoE and don't want to spend the bucks on a PoE switch.

That's not entirely correct. Both 3750 and 3750-E can be stacked via StackWise ports. Here is whitepaper from Cisco -

I'm pretty sure that most (if not all) Cisco access point include a power injector because they are included with the 1310AG and 1240AG's I have ordered.

Its an optional order item. You must just order them bundled as part of the order. I've had to buy them seperately when I get my 1301AGs.

I did some checking and found that the power injector is indeed a $59 list price option. We regularly purchase the 1131AG AP's and we never purchase the power injector but our order always includes a power cord, which is a no cost option. Included in the box is a power cord, AND a power injector!!! Very, very interesting.