Protocol
Features

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 Priority
2-Highest IP (tiebreaker)

Master Router: (*)
1-Highest Priority
2-Highest IP (tiebreaker)

Active Virtual Gateway:
1-Highest Priority
2-Highest IP (tiebreaker)

Optimization features

Tracking

yes

yes

yes

Preempt

yes

yes

yes

Timer adjust

yes

yes

yes

Traffic 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.