NM vs HWIC

zeeshan.kamal · ‎04-07-2009

Hi

Can anyone tell me the difference between NM and HWIC. I want to use almost 8 internet connections on 2821. All connections are on Ethernet. Which card should i take HWIC-4ESW or NM-16ESW ?

Sushil Kumar Katre · ‎04-07-2009

Hi Zeeshan,

NM and HWIC are two different kind of Slots available on a router which are compatible with a specific set of modules.

If I am not mistaken the internal connectivity for NM and HWIC is a little different.

Cisco 2821 router has ONE NM slot and FOUR HWIC slots. So you need to choose the NM module judiciously since you just have one slot on the router.

-> Sushil

Leo Laohoo · ‎04-07-2009

In addition, NM-16ESW comes in two variety:

NM-16ESW is a Layer 2 Switch module; and

NME-16ESW is a Layer 2/3 Switch module (a mini-3750)

Hope this helps.

Sushil Kumar Katre · ‎04-07-2009

Sorry Zeeshan, I missed the main point on the selection of HWIC or NM.

As pointed by Leo this specific NM module can act as L2 or L3 switch. This means that you can terminate your internet links and assign the IP Addresses directly on the ehternet interface.

While HWIC-4ESW is a L2 switch module,meaning you'll not be able to assign ip addresses directly on the interface. However you can use SVIs and make it work.

Probably the cost of two HWICs will be less than the cost of the NM.

-> Sushil

Leo Laohoo · ‎04-07-2009

There's another one you can check for Layer 2: HWIC-9ESW.