Gigabit Ethernet And Remote Fault Indication; Sffd Recommendations - Avaya 8800 Planning And Engineering, Network Design

Redundant network design
Figure 12: 100BASE-FX FEFI
With Avaya-to-Avaya connections, to avoid loss of connectivity for devices that do not support FEFI,
you can use VLACP as an alternative failure detection method. For more information, see
end fault detection and VLACP

Gigabit Ethernet and remote fault indication

The 802.3z Gigabit Ethernet standard defines remote fault indication (RFI) as part of the
autonegotiation function. RFI provides a means for the stations on both ends of a fiber pair to be
informed when a problem occurs on one of the fibers. Because RFI is part of the autonegotiation
function, if autonegotiation is disabled, RFI is automatically disabled. Therefore, Avaya]
recommends that autonegotiation be enabled on Gigabit Ethernet links when autonegotiation is
supported by the devices on both ends of a fiber link.
For information about autonegotiation for 10 and 100 Mbit/s links, see
Autonegotiation recommendations

SFFD recommendations

The Ethernet switching devices listed in the following table do not support autonegotiation on fiber-
based Gigabit Ethernet ports. These devices are unable to participate in remote fault indication
(RFI), which is a part of the autonegotiation specification. Without RFI, and in the event of a single
fiber strand break, one of the two devices may not detect a fault, and continues to transmit data
even though the far-end device does not receive it.
June 2016
on page 57.
on page 36.
Planning and Engineering — Network Design
Comments on this document? infodev@avaya.com
End-to-
10/100BASE-TX
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