Skipping the Access Layer

[NETAD]

Hi guys, 

Why is it not recommended to omit the access layer and plug users directly into the aggregation switches? I know we can do that with the collapsed core design where we merge both the aggregation and the core layer together. My company is looking to stand up a new buidling with some 3850 stacks as distribution and 4000 series for gateways but connect users traffic directly to the 3850 stacks. 

Thanks 

[Seb Rupik · Accepted solution]

Hi there,

The difference between access and aggregation/ distribution switches comes down to capability/ performance and cost per port. The closer you move towards the core the great these two functions become.

That said the 3850 is an access layer switch, so it is fine to connect users straight to it.

cheers,

Seb.

[Steven Williams · Accepted solution]

Aggregation layer for the case of Design really pertains to the datacenter design. Usually the aggregation switch is a Nexus. Otherwise when dealing with regular networking "aggregation" is essentially the "Distribution" layer