Which First Hop Redundancy Protocol is an IEEE Standard?
A.
GLBP
B.
HSRP
C.
VRRP
D.
OSPF
Explanation:
A comparison of the three First Hop Redundancy Protocols are listed below:
ProtocolFeatures
HSRP
(Hot Standby Router protocol)
VRRP
(Virtual Redundancy Router Protocol)
GLBP
(Gateway Load Balancing Protocol)
Router role
– 1 active router.- 1 standby router.- 1 or more listening routers.
– 1 master router.- 1 or more backup routers.
– 1 AVG (Active Virtual Gateway).- up to 4 AVF routers on the group (Active Virtual Forwarder) passing traffic.- up to 1024 virtual routers (GLBP groups) per physical
interface.
– Use virtual ip address.
– Can use real router ip address, if not, the one with highest priority become master.
– Use virtual ip address.
Scope
Cisco proprietary
IEEE standard
Cisco proprietary
Election
Active Router:1-Highest Priority2-Highest IP (tiebreaker) Master Router: (*)1-Highest Priority2-Highest IP (tiebreaker) Active Virtual Gateway:1-Highest Priority2-
Highest IP (tiebreaker) Optimization features
Tracking
yesyes
yes
Preempt
yes
yes
yes
Timer adjustments
yes
yes
yesTraffic type
224.0.0.2 udp 1985 (version1)224.0.0.102-udp 1985 (version2) 224.0.0.18 IP 112
224.0.0.102 udp 3222
Timers
Hello 3 seconds
Advertisement 1 second
Hello 3 seconds
(Hold) 10 seconds
(Master Down Interval)3 * Advertisement + skew time
(Hold) 10 seconds
(Skew time)(256-priority) / 256
Load-balancing functionality
– Multiple HSRP group per interface/SVI/routed int.
– Multiple VRRP group per interface/SVI/routed int.
Load-balancing oriented- Weighted algorithm.- Host-dependent algorithm.
– Round-Robin algorithm (default).
Requires appropriate distribution of Virtual GW IP per Clients for optimal load-balancing.(generally through DHCP)
Requires appropriate distribution of Virtual GW IP per Clients for optimal load-balancing.(generally through DHCP)
Clients are transparently updated with virtual MAC according to load-balancing algorithm through ARP requesting a unique virtual gateway.
http://cciethebeginning.wordpress.com/2008/08/23/router-high-availability-protocol- comparison-2/