METRODATA NetTESTER FAMILY USER MANUAL
76-02-107 Rev.A
Page 63 of 133
For fibre ports, the speed setting sets the operating speed of the port with valid
options of:
100M
100 Base FX Fast Ethernet
1000M
1000 Base X Gigabit Ethernet
Auto
In the auto mode, the SFP module is read and the port parameters
are set according to the SFP type installed. If a 1000BaseX SFP is
installed the port will operate at 1000M, whilst if a 100BaseFX or
OC3 SFP is installed, the port will operate at 100M.
14.1.3.4 Duplex
Menu Tree: Main Set-Up /
S
ettings /
W
AN Port /
D
uplex
The Duplex parameter has two meanings depending upon whether auto negotiation
is enabled or not.
When Auto Negotiation is disabled, the Duplex setting sets the operating mode of
the port with valid options of:
Half
Half Duplex
Full
Full Duplex
When Auto Negotiation is enabled, the duplex setting defines the maximum mode
advertised to the link partner and the option changes to max duplex. The options are
as below:
Half
Advertise Half Duplex
Full
Advertise Half Duplex, Full Duplex
14.1.3.5 Auto Negotiation
Menu Tree: Main Set-Up /
S
ettings /
W
AN Port /
A
uto-Negotiation
Auto Negotiation allows the port to automatically determine the best operating
parameters for the port. If both link partners support auto-negotiation then they will
select the best mode that is supported by both devices.
If one link partner does not support auto negotiation, an auto negotiating link partner
will be able to determine the link speed, however it will be unable to determine the
duplex mode so will default to the half-duplex state.
An auto port connected to a non-auto port is a very common fault on networks
leading to errors on the line when significant traffic is flowing but appearing to
operate normally when diagnostics like ping are used to test the link.
Note, Auto-Negotiation is mandatory in 1000M mode so cannot be disabled unless
the speed selection is either 10M or 100M.