Which two design models offer the fastest convergence time following a distribution switch failure? (Select two.)

Question

Options

• ALoop-free U topology
• BLoop-free Invert-U topology
• CVirtual switch model
• DRouted access model
• EMultitier triangle access model with Layer 3 distribution-to-distribution link

• A
  3% (1)
• B
  9% (3)
• C
  85% (28)
• E
  3% (1)

Explanation

The virtual switch model (C) - such as Cisco VSS or StackWise Virtual - presents two physical distribution switches as a single logical device. Because the access layer sees one gateway with no STP topology change and no FHRP failover needed, convergence after a member switch failure is near-instantaneous (often sub-second). The routed access model (D) runs a routing protocol (e.g., EIGRP or OSPF) all the way to the access layer; routing reconverges faster than STP-based designs and eliminates FHRP delay entirely. Loop-free U and Inverted-U topologies (A, B) still rely on STP and FHRP, making convergence slower. The multitier triangle model (E) also depends on STP and FHRP at the distribution layer.

No community discussion yet for this question.