
Explanation/Reference:
Explanation:
Layer 2 between distribution and access layers, with a Layer 3 link between the distribution switches
-> Support Layer 2 VLANs spanning multiple access layer switches across the distribution switches Layer 2 between distribution and access layers, with a Layer 2 link between the distribution switches
-> FHRP for convergence, no VLANs span between access layer switches across the distribution switches VSS -> Convergence (FHRP) is not an issue
The following are recommended best practices at the distribution layer:
Use First-Hop Redundancy Protocols. Hot Standby Router Protocol (HSRP) or Gateway Load

Balancing Protocol (GLBP) should be used if you implement Layer 2 links between the Layer 2 access switches and the distribution layer.
Use Layer 3 routing protocols between the distribution and core switches to allow for fast convergence

and load balancing.
Use the distribution switches to connect Layer 2 VLANs that span multiple access layer switches.

Use Virtual Switching System (VSS) to eliminate the use of STP and the need for HSRP.

Cisco Press CCDA 640-864 Official Certification Guide Fourth Edition, Chapter 3