Avaya Virtual Services Platform 9000 Series Configuration Manual page 11

operation does not comply with the latest IEEE 802.3ab standard,which recommends to use
Autonegotiation on 1000BASE-T ports for 1000Mbit/s links.
Remote Fault Indication and Far End Fault Indication
The 802.3z Gigabit Ethernet standard defines Remote Fault Indication (RFI) as part of the
Autonegotiation function. The stations on both ends of a fiber pair use RFI to learn if a problem
occurs with one of the fibers. Because RFI is part of the Autonegotiation function, if you disable
Autonegotiation, you automatically disable RFI. Therefore, Avaya recommends that you
enable Autonegotiation on Gigabit Ethernet links in all cases where the devices on both ends
of a fiber link support Autonegotiation.
10 Gigabit Ethernet automatically uses Far End Fault Indication (FEFI). Remote failure is
detected at the Media Access Control (MAC) level. Upon receiving FEFI notification from the
remote site, the 10 Gbit/s LAN module port changes its link state to nonoperational.
Custom Autonegotiation Advertisement
The 10/100/1000 Mbit/s ports support Custom Autonegotiation Advertisement (CANA). Use
CANA to control the speed and duplex settings that these modules advertise during
Autonegotiation sessions between Ethernet devices. You can only establish links using these
advertised settings, rather than at the highest common supported operating mode and data
rate.
Use CANA to provide smooth migration from 10/100 Mbit/s to 1000 Mbit/s on host and server
connections. Using Autonegotiation only, the switch always uses the fastest possible data
rates. In scenarios where uplink bandwidth is limited, CANA provides control over negotiated
access speeds, and thus improves control over traffic load patterns.
Virtual Services Platform 9000 supports CANA on 10/100/1000 Mbit/s RJ-45 ports only. To use
CANA, you must enable Autonegotiation.
802.3x flow control for Gigabit Ethernet
Use flow control to protect against packet loss. Flow control prevents Ethernet ports from
receiving more data than they can process.
The 802.3x flow control mechanism is effective only at the Data Link Layer (Layer 2). When
the Virtual Services Platform 9000 routes packets, flow control packets are ignored.
The Ethernet modules support IEEE 802.3x flow control in the following ways:
temporarily halt packet transmission when an 802.3x Pause frame is received from the
remote end
Note:
802.3x flow control pause frames are not transmitted by default. Transmit flow control can
be enabled if required.
Flow control can be enabled on ports of any speed.
Maximum transmission unit and jumbo frames
Jumbo frames are larger than the maximum Ethernet frame size, or maximum transmission
unit (MTU) specified in the IEEE 802.3 standard. For untagged frames, the maximum standard
Configuration — Ethernet Modules
Ethernet module concepts
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