L2 10/100 SNMP-Manageable
Switching Media Converter
LMC5118C — LMC5119C — LMC5120C — LMC5121C
LMC5122C — LMC5123C — LMC5124C — LMC5125C
LMC5126C — LMC5127C
A A b b o o u u t t L L 2 2 1 1 0 0 / / 1 1 0 0 0 0
The L L 2 2 1 1 0 0 / / 1 1 0 0 0 0 is an SNMP-manageable, IEEE 802.3 10/100 switching
media converter from Black Box which converts both speed and media.
L2 10/100 modules provide a single conversion between:
• 10Base-T twisted pair and 100Base-FX multi-mode fiber, or
• 10Base-T twisted pair and 100Base-FX single-mode fiber, or
• 100Base-TX twisted pair and 100Base-FX multi-mode fiber, or
• 100Base-TX twisted pair and 100Base-FX single-mode fiber.
L2 10/100 TX/FX modules (
LMC5118C, LMC5119C, LMC5120C, LMC5121C
for regular duplex fiber while L2 10/100 TX/SSFX modules (
LMC5123C, LMC5124C, LMC5125C LMC5126C, LMC5127C
fiber. L2 10/100 TX/SSFX Modules allow two wavelengths to share one fiber
strand — Full-Duplex data travels on different wavelengths (1310 nm and 1550
nm) — doubling the capacity of installed fiber.
L2 10/100 modules feature one RJ-45 connector and one pair of ST or SC
fiber connectors (single-strand fiber versions have one SC fiber connector). L2
10/100 modules require one slot in an SNMP-manageable High Density Media
Converter System II chassis or any SNMP Manageable Media Converter chassis
from Black Box. Please refer to your chassis' manual for more information.
C C o o n n f f i i g g u u r r a a t t i i o o n n I I n n s s t t r r u u c c t t i i o o n n s s
End-users may configure L2 10/100 modules for various features. See the
DIP Switch Location and Configuration Settings chart on page 2 for information
on available features. The following sections include instructions for configur-
ing both managed (via an SNMP-compatible management application like
iView) and unmanaged modules.
N O T E
Management software will override any hardware settings (e.g., jumper, switch, etc.), so you MUST config-
ure a module that will be managed via the software. Until a module installed in a managed chassis is con-
figured via the software, the module (and its LEDs) may not work properly.
M M a a n n a a g g e e d d M M o o d d u u l l e e s s
To manage one or more SNMP Modules, an SNMP agent must be present in
the chassis: High Density Media Converter System II chassis include embedded
management; other SNMP-manageable media converters require a Master
Module.
When configuring managed modules, install the module first (see
page 4), then configure it using the management software. Within iView for
SNMP-Manageable Media Converters, features and troubleshooting functions
are configured in the Module Detail section under the picture of the module.
See the iView online help file for more information.
I N S T A L L A T I O N
T I P
When testing, Black Box recommends you test your module first in an unmanaged environment. To do
this, turn the SNMP management switch to OFF on an Media Converter System II chassis, or remove the
management module from an iMcV Series chassis. Follow the unmanaged configuration instructions,
then install the module, connect the cables and test the LEDs. When finished, reactivate management
and configure the unit via the software.
1
U U n n m m a a n n a a g g e e d d M M o o d d u u l l e e s s
Before installing, L2 10/100 modules may be configured for LinkLoss,
FiberAlert, Auto-Negotiation, duplex mode and speed. The following illustra-
tion and charts include the available Dip Switch locations and configuration set-
tings for L2 10/100 modules.
D D I I P P S S w w i i t t c c h h L L o o c c a a t t i i o o n n a a n n d d C C o o n n f f i i g g u u r r a a t t i i o o n n S S e e t t t t i i n n g g s s
) are
LMC5122C,
) are for single-strand
Auto-Negotiation & Selective Advertising Configuration Chart
Auto-
Negotiation
Advertise All
ON
Selective
ON
Advertising
No
* OFF
Advertising
Flow Control is used to throttle the END device to avoid dropping packets during network congestion.
*
Selective Advertising is NOT an option when Auto-Negotiation is disabled.
**
Full-Duplex Flow Control will Advertise ONLY in Full-Duplex Mode
Full-Duplex Control functions ONLY if link partner (end devices) also has Flow Control
*** Half-Duplex Flow Control DOES NOT Advertise
X = Switch setting is ignored.
A A b b o o u u t t L L i i n n k k L L o o s s s s a a n n d d F F i i b b e e r r A A l l e e r r t t
L2 10/100 modules include the following troubleshooting features:
• FX LinkLoss (a.k.a. "Fiber LinkLoss" or just "LinkLoss")
• TX LinkLoss (a.k.a. "Twisted Pair LinkLoss" or "Reverse LinkLoss")
• FiberAlert*
* FiberAlert is not available/required on single-strand fiber versions of L2 10/100 modules.
FiberAlert and LinkLoss are advanced troubleshooting features that can help
locate "silent failures" on your network. However, it is vital that you understand
exactly how FiberAlert and LinkLoss work, and how they will react in your net-
work configuration, before attempting to install the enclosed module(s).
Installing modules without understanding the effects of LinkLoss can cause perfectly
functioning units to appear flawed or even dead.
A A b b o o u u t t L L i i n n k k I I n n t t e e g g r r i i t t y y
During normal operation, link integrity pulses are transmitted by all point-
to-point Ethernet devices. When an Black Box media converter receives valid
link pulses, it knows that the device to which it is connected is up and send-
ing pulses, and that the copper or fiber cable coming from that device is
intact. The appropriate "LNK" (link) LED is lit to indicate this.
The Black Box media converter also sends out link pulses from its copper
and fiber transmitters, but normally has no way of knowing whether the cable
to the other device is intact and the link pulses are reaching the other end.
Dip Switch Settings
S1
Function
Default
1
Auto-Negotiation
ON
2
TX HDX(ON) or TX FDX(OFF)
OFF
3
TX 100 or TX 10(OFF)
OFF
4
TX LinkLoss
OFF
5
FX LinkLoss
OFF
6
FX HDX or FX HDX(OFF)
OFF
FiberAlert
7
OFF
8
Selective Advertising
OFF
S2
Function
Default
1
Full-Duplex – Flow Control
OFF
2
Half-Duplex – Flow Control
OFF
3-8
Factory Default
Do Not Change
Selective
FDX
HDX
FDX/HDX
10/100
Advertising
Flow Control
Flow Control
OFF
X
X
X
N/A
FDX
10/100
** ON/OFF
N/A
ON
HDX
10/100
X
*** ON/OFF
FDX
10/100
N/A
N/A
X
HDX
10/100
N/A
*** ON/OFF
2
Both TX and FX LinkLoss allow this information to be obtained, even when phys-
ical access to a remote device (and its link integrity LED) is not available.
W W h h a a t t I I s s F F X X L L i i n n k k L L o o s s s s ? ?
FX LinkLoss is a troubleshooting feature. When a fault occurs on the fiber
segment of a conversion, FX LinkLoss detects the fault and passes this informa-
tion to the twisted pair segment. If a media converter is not receiving a fiber
link, FX LinkLoss disables the transmitter on the media converter's twisted pair
port, resulting in a loss of link on the device connected to the twisted pair port.
W W h h a a t t I I s s T T X X L L i i n n k k L L o o s s s s ? ?
TX LinkLoss is another troubleshooting feature. When a fault occurs on the
twisted pair segment of a conversion, TX LinkLoss detects the fault and passes this
information to the fiber segment. If a media converter is not receiving a twisted
pair link, TX LinkLoss disables the transmitter on the media converter's fiber port,
resulting in a loss of link on the device connected to the fiber port.
W W h h a a t t I I s s F F i i b b e e r r A A l l e e r r t t ? ?
FiberAlert minimizes the problems associated
with the loss of one strand of fiber. If a strand is
unavailable, the Black Box device at the receiv-
er end notes the loss of link. The device will
then stop transmitting data and the link signal
until a signal or link pulse is received. The result
is that the link LED on BOTH sides of the fiber connection will go out indicating
a fault somewhere in the fiber loop. Using FiberAlert, a local site administrator
is notified of a fault and can quickly determine where a cable fault is located.
N O T E
FiberAlert should only be enabled on one side of a media conversion. Enabling it on both sides
would keep both transmitters off indefinitely.
U U s s i i n n g g L L i i n n k k L L o o s s s s a a n n d d F F i i b b e e r r A A l l e e r r t t
FiberAlert / LinkLoss Compared
Feature
In a typical main site to remote
FiberAlert
site media conversion, Black Box
FX LinkLoss
recommends you enable your
TX LinkLoss
media converters' troubleshooting features as follows:
•FX LinkLoss: Main Site
•FiberAlert: Remote Site Only
This will ensure that any faults, no matter where they occur, can be detected
by an administrator at the main site. If you are unsure of how best to implement
these features in your configuration, please contact Black Box technical support
at 724-746-5500.
A A u u t t o o C C r r o o s s s s F F e e a a t t u u r r e e f f o o r r T T w w i i s s t t e e d d P P a a i i r r C C o o n n n n e e c c t t i i o o n n s s
The twisted pair port of the L2 10/100 module includes AutoCross, a feature
which automatically selects between a crossover workstation or pass-through/
repeater hub connection depending on the connected device.
A A u u t t o o - - N N e e g g o o t t i i a a t t i i o o n n , , D D u u p p l l e e x x M M o o d d e e a a n n d d S S p p e e e e d d
The twisted pair port on L2 10/100 auto-negotiates for speed and duplex
mode. These modules also provide the option of manually setting the speed and
duplex mode if the connected devices do not have the ability to auto-negotiate,
3
Fault Location
Disabled LEDs
Fiber
Fiber
Fiber
Twisted Pair
Twisted Pair
Fiber
•TX LinkLoss: Remote Site
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