Which protocol allows the network to fully use standby routers in a redundancy group without additional administrative burden?
A. HSRP
B. VRRP
C. GLBP
D. IRDP
Correct Answer: C
Explanation/Reference:
Answer:
Gateway Load Balancing Protocol (GLBP) allows the network to fully utilize standby routers in a redundancy group. Unlike HSRP and VRRP, GLBP allows automatic selection and simultaneous use of multiple gateways. It also allows for router load balancing from a segment without using different host configuration as in HSRP.
Hot Standby Router Protocol (HSRP) and Virtual Router Redundancy Protocol (VRRP) provide gateway redundancy, but only one router in a group can forward traffic for a redundancy group. The bandwidth and resources associated with the non-actively forwarding routers are wasted. GLBP allows this wasted bandwidth and resources to be utilized by providing automatic selection and use of multiple available gateways to destinations.
ICMP Router Discovery Protocol (IRDP) is an extension of the Internet Control Message Protocol (ICMP) that allows routers to advertise useful routes. IRDP does not require hosts to recognize routing protocols, nor does it require manual configuration.
Objective:
Infrastructure Services Sub-Objective:
Configure and verify first-hop redundancy protocols
References:
Cisco > Cisco IOS IP Application Services Configuration Guide, Release 12.4 > Part 1: First Hop Redundancy Protocols > Configuring GLBP
Explanation/Reference:
Answer:
Gateway Load Balancing Protocol (GLBP) allows the network to fully utilize standby routers in a redundancy group. Unlike HSRP and VRRP, GLBP allows automatic selection and simultaneous use of multiple gateways. It also allows for router load balancing from a segment without using different host configuration as in HSRP.
Hot Standby Router Protocol (HSRP) and Virtual Router Redundancy Protocol (VRRP) provide gateway redundancy, but only one router in a group can forward traffic for a redundancy group. The bandwidth and resources associated with the non-actively forwarding routers are wasted. GLBP allows this wasted bandwidth and resources to be utilized by providing automatic selection and use of multiple available gateways to destinations.
ICMP Router Discovery Protocol (IRDP) is an extension of the Internet Control Message Protocol (ICMP) that allows routers to advertise useful routes. IRDP does not require hosts to recognize routing protocols, nor does it require manual configuration.
Objective:
Infrastructure Services Sub-Objective:
Configure and verify first-hop redundancy protocols
References:
Cisco > Cisco IOS IP Application Services Configuration Guide, Release 12.4 > Part 1: First Hop Redundancy Protocols > Configuring GLBP
