Which two statements are true about best practices in VLAN design?

Which two statements are true about best practices in VLAN design? (Choose two.)

A.
Routing should occur at the access layer if voice VLANs are utilized. Otherwise, routing
should occur at the distribution layer.

B.
Routing should always be performed at the distribution layer.

C.
VLANs should be localized to a switch.

D.
VLANs should be localized to a single switch unless voice VLANs are being utilized.

E.
Routing should not be performed between VLANs located on separate switches.

Explanation:
In the distribution layer, uplinks from all access layer devices are aggregated, or come
together. The distribution layer switches must be capable of processing the total volume of

traffic from all the connected devices. These switches should have a port density of highspeed links to support the collection of access layer switches.
VLANs and broadcast domains converge at the distribution layer, requiring routing, filtering,
and security. The switches at this layer must be capable of performing multilayer switching
with high throughput. Only certain Catalyst switch models can provide multilayer switching;
be sure to understand which ones can do this.
A switched environment offers the technology to overcome flat network limitations. Switched
networks can be subdivided into VLANs. By definition, a VLAN is a single broadcast domain.
All devices connected to the VLAN receive broadcasts from other VLAN members. However,
devices connected to a different VLAN will not receive those same broadcasts. (Naturally,
VLAN members also receive unicast packets directed toward them from other VLAN
members.)
A VLAN consists of defined members communicating as a logical network segment. In
contrast, a physical segment consists of devices that must be connected to a physical cable
segment. A VLAN can have connected members located anywhere in the campus network,
as long as VLAN connectivity is provided between all members. Layer 2 switches are
configured with a VLAN mapping and provide the logical connectivity between the VLAN
members.