Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2InfrastructureMedium
A network engineer is configuring a new Layer 3 switch to act as a default gateway for multiple VLANs in a campus network. To ensure high availability, the engineer needs to implement a first-hop redundancy protocol that allows multiple switches to share the same virtual IP address and MAC address. Which protocol meets this requirement and is Cisco proprietary?
- AGLBP
- BHSRP
- CVRRP
- DCARP
Show answer & explanationAnswer & explanation
Correct answer: B. HSRP
Hot Standby Router Protocol (HSRP) is a Cisco proprietary FHRP that provides high availability for default gateways. It allows two or more routers/switches to share a single virtual IP and MAC address, with one device acting as active and the other as standby.
Why the other options are wrong
- A. GLBP (Gateway Load Balancing Protocol) is Cisco proprietary, but it provides load balancing using multiple virtual MAC addresses, not a single shared virtual MAC as requested.
- C. VRRP (Virtual Router Redundancy Protocol) is an open standard FHRP, not Cisco proprietary.
- D. CARP (Common Address Redundancy Protocol) is an open-source FHRP, not Cisco proprietary.
Hot Standby Router Protocol (HSRP)
A Cisco proprietary First-Hop Redundancy Protocol (FHRP) that provides default gateway redundancy by allowing multiple routers/switches to share a virtual IP and MAC address.
- Cisco proprietary.
- Uses active/standby roles.
- Shares a single virtual IP and MAC address.
- Provides gateway redundancy.
Memory trick: HSRP: Hot Standby, Cisco's reliable pair.