User's Manual

7
Figure 2 MPO connector
Optical parameters
NOTE:
A
vera
g
e transmit and receive power ran
g
es are provided for transceiver modules in this guide.
Transmit power
Transmit power is the power at which the transmitter of a fiber transceiver module transmits optical
signals, in dBm.
Receive power
Receive power is the power at which the receiver of a fiber transceiver module receives optical signals,
in dBm.
Copper transceiver modules
Copper transceiver modules transmit signals over Category-5 unshielded twisted pair (UTP). UTP
transmission cover shorter distances than fiber transmission and can be used in small-sized networks
only.
The HP Comware-Based devices support the HP X120 1G SFP RJ45 T Transceiver (JD089B) copper
transceiver modules.
Transmission distance
Through UTP cables, signals can be transmitted over a distance of 100 m (328.08 ft.) only. This is
because signals attenuate during transmission through the UTP cables.
Attenuation refers to the dissipation of the power of a transmitted signal as it travels over a cable.
Attenuation occurs because signal transmission suffers certain resistance from the cable, which weakens
the signals as they travel over the cable. When signals are transmitted over a very long distance, signal
strength decreases significantly, causing the signal-to-noise ratio to drop below the accepted level. This
makes it impossible to distinguish between signals and noise, resulting in decision errors.
When signals are to be transmitted over a short distance, use copper transceiver modules only.