Is the Distribution Layer Still Needed?

arnie_apesacrappin wonders: "I'm in the process of designing the network for a new building in what I would consider a small to medium sized company. It is on the scale of tens of access layer switches, not hundreds. There is a ongoing argument about the need for a distribution layer. My position is that with today's layer 2/3 switches in the core, the distribution layer is outdated for a network of this size. The layer 2/3 core can provide all the aggregation services of the old distribution layer and the routing/filtering functionality of the core with better price and performance. My opponents can only argue that having a distribution layer is the standard. So, are there good reasons for having a distribution layer in a small to medium network? If you were going to argue against the distribution layer, what points would you make?"

Comments

Re:It can be done.

[Kaamoss]

That's the real key, if the network can't be scalable then you're not setting your self up to do further work for the company. When you give someone a solution it should have the ability to grow with them. In the end it's almost allways cheaper to go with the more complete solution than the simple one.

Spoken like a true CCNA

[Schezar]

The very concept was never spoken of at university (Rochester Institute of Technology), nor has it ever come up in work (IBM).

Those three "layers" are abstractions, nothing more. The "distribution" layer is simply a term for traffic shaping and optimization. It's very useful in eliminating excess resource use on beleagured routers. Eliminating the layer is nothing more than simplifying your backbone architecture. There is no "layer" to eliminate except the theoretical one.

It always amazes me how Cisco-certified (not making any acusations here) network techs speak an entirely different language from university-educated ones. They talk about Cisco-specific concepts like they're set in stone universally, and use Cisco jargon for common and/or basic concepts.

There are other options besides Cisco, and not every network fits within the nomenclature of Cisco Jargon. You'd do yourself an immense favour to lean more about generic architecture concepts.

I don't want to sound mean, but a Cisco cert is about as useful as an MSCE.