Intel 480T, User Manual

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18
C H A P T E R 1 Overview
1.
T
HE TRANSMITTER OUTPUT POWER LEVEL FOR THE
1000BASE-LX70
IS
+5
D
B
M
. T
HE
MAXIMUM ALLOWABLE RECEIVER INPUT POWER LEVEL IS
-3
D
B
M
. T
HEREFORE
,
THERE IS A
MINIMUM OF
8
D
B
LOSS REQUIRED FOR THE LINK TO OPERATE WITHOUT ERRORS
. T
HIS MINIMUM
REQUIRED LOSS CAN BE ACHIEVED USING A FIBER LENGTH OF
32
KM
(0.25
D
B/
KM PROVIDES
8
D
B
LOSS
),
OR BY ADDING
10
D
B
OF FIXED OPTICAL ATTENUATOR AT THE RECEIVER END
.
Full-Duplex Support
The 480T switch provides full-duplex support for all ports. Full-
duplex mode allows frames to be transmitted and received
simultaneously and, in effect, doubles the bandwidth available on a
link. All 100/1000 Mbps ports on the switch autonegotiate for half-
or full-duplex operation. The 1000BASE-SX, 1000BASE-LX and
1000LH ports operate in full-duplex mode, only.
Virtual LANs (VLANs)
The local management software has a VLAN feature that enables you
to construct your broadcast domains without being restricted by
physical connections. A VLAN is a group of location- and topology-
independent devices that communicate as if they were on the same
physical local area network (LAN).
Implementing VLANs on your network has the following three
advantages:
• They help to control broadcast traffic. If a device in VLAN
Marketing transmits a broadcast frame, only VLAN Marketing
devices receive the frame.
• They provide extra security. Devices in VLAN Marketing can only
communicate with devices on VLAN Sales using routing services.
Receiver
Optical Input Power Sensitivity -20dBm
Optical Input Power Maximum -3dBm
Operating Wavelength 1200nm 1560nm
Table 3: 1000LH Specifications (continued)
Parameter Minimum Typical Maximum