Architectural Differences - Foundry Networks Switch and Router Installation And Configuration Manual

Foundry Switch and Router Installation and Configuration Guide
Comparison of VRRP, VRRPE, and FSRP
This section compares Foundry's router redundancy protocols.
VRRP
VRRP is a standards-based protocol, described in RFC 2338. The Foundry implementation of VRRP contains the
features in RFC 2338. The Foundry implementation also provides the following additional features:
• Track ports – A Foundry feature that enables you to diagnose the health of all the Layer 3 Switch's ports used
by the backed-up VRID, instead of only the port connected to the client sub-net. See "Track Ports and Track
Priority" on page 21-5.
• Suppression of RIP advertisements on Backup routes for the backed up interface – You can enable the Layer
3 Switches to advertise only the path to the Master router for the backed up interface. Normally, a VRRP
Backup router includes route information for the interface it is backing up in RIP advertisements.
Foundry Layer 3 Switches configured for VRRP can interoperate with third-party routers using VRRP.
VRRPE
VRRPE is a Foundry protocol that provides the benefits of VRRP without the limitations. In fact, VRRPE
combines the benefits of Foundry's VRRP and FSRP (see "FSRP"). VRRPE is unlike VRRP and is like FSRP in
the following ways:
• There is no "Owner" router. You do not need to use an IP address configured on one of the Layer 3 Switches
as the virtual router ID (VRID), which is the address you are backing up for redundancy. The VRID is
independent of the IP interfaces configured in the Layer 3 Switches. As a result, the protocol does not have
an "Owner" as VRRP does.
• There is no restriction on which router can be the default master router. In VRRP, the "Owner" (the Layer 3
Switch on which the IP interface that is used for the VRID is configured) must be the default Master.
Foundry Layer 3 Switches configured for VRRPE can interoperate only with other Foundry Layer 3 Switches.
FSRP
The Foundry Standby Router Protocol (FSRP) is another Foundry router redundancy protocol that provides
many of the same features as Foundry's implementation of VRRP and VRRPE. However, FSRP does not provide
authentication, which VRRP and VRRPE do. In addition, FSRP allows only one backup router.
FSRP is available only on Foundry Layer 3 Switches.

Architectural Differences

The protocols have the following architectural differences.
Management Protocol
• VRRP – VRRP routers send VRRP Hello and Hello messages to IP Multicast address 224.0.0.18.
• VRRPE – VRRPE sends messages to destination MAC address 01-00-5E-00-00-02 and destination IP
address 224.0.0.2 (the standard IP multicast address for "all routers").
• FSRP – FSRP sends management traffic to a user-configured unicast address.
Virtual Router IP Address (the address you are backing up)
• VRRP – The virtual router IP address is the same as an IP address or virtual interface configured on one of
the Layer 3 Switches, which is the "Owner" and becomes the default Master.
• VRRPE – The virtual router IP address is the gateway address you want to backup, but does not need to be
an IP interface configured on one of the Layer 3 Switch's ports or a virtual interface.
• FSRP – The virtual router IP address is a user-configured virtual IP address.
21 - 8 December 2000