RuggedCom RuggedRouter RX1100 - Manual (Page 234)

26. Configuring Layer 2 Tunnels
Revision 1.14.3 234 RX1000/RX1100™
26. Configuring Layer 2 Tunnels
26.1. Introduction
RuggedRouter is capable of extending the range of services that communicate solely via Layer 2
protocols (i.e. at the level of Ethernet) by tunneling them over routed IP networks. The Layer 2 Tunnel
Daemon supports the IEC61850 GOOSE protocol as well as a generic mechanism for tunneling by
Ethernet type.
This chapter familiarizes the user with:
• Configuring GOOSE tunnels
• Configuring generic Layer 2 tunnels
• Viewing tunnel status and statistics
• Tracing tunnel activity
26.1.1. IEC61850 GOOSE Fundamentals
IEC61850 is an international standard for substation automation. It is a part of the International
Electrotechnical Commission’s (IEC) Technical Committee 57 (TC57) architecture for electric power
systems. An important feature of IEC61850 is the fast transfer of event data. Transfers of
Generic Substation Events (GSEs) are accomplished through the GOOSE (Generic Object Oriented
Substation Event) protocol.
IEC61850 uses Layer 2 multicast frames to distribute its messages and hence is incapable of
operating outside of a switched Ethernet Network. The GOOSE tunnel feature provides a capability
to bridge GOOSE frames over a WAN.
GOOSE tunnels provide the following features:
• GOOSE traffic is bridged over the WAN via UDP/IP.
• One GOOSE traffic source can be mapped to multiple remote router Ethernet interfaces in mesh
fashion.
• To reduce bandwidth consumption, GOOSE daemons may be located at each of the “legs” and
at the center of a star network. The centrally located daemon will accept GOOSE packets and
re-distribute them.
• Statistics reports availability of remote GOOSE daemons, packet counts and Round Trip Time
(RTT) for each remote daemon.
• When Virtual Router Redundancy Protocol (VRRP) is employed, GOOSE transport is improved
by sending redundant GOOSE packets from each VRRP gateway.
26.1.1.1. GOOSE Tunnel Implementation Details
The GOOSE protocol is supported by the Layer 2 Tunnel Daemon. The daemon listens to configured
Ethernet interfaces and to the network itself (i.e. for tunnel connections from other daemon instances)
on a configurable UDP port.