Chapter 4: Remote Management HTTP and SNMP
Firmware upgrades may be transferred to the converter via the LAN port (or DS3/E3 port, if management of
the remote converter is enabled). A hardware reset, which will interrupt link data flow for several seconds,
will be required at some point after the transfer in order to begin using the new firmware. Instructions for
performing the TFTP transfer are included with all firmware shipments. The most common source of
problems when performing upgrades is attempting a TFTP transfer in ASCII or text mode rather than binary
or image mode, resulting in a “too large” or “out of room” type TFTP error.
Feature Activation/Upgrade
For activation of additional capabilities of the converter after initial purchase, supply the factory with the
serial number from the
front
of your converter (also shown at the HTTP management page for recent
firmware) and purchase an alphanumeric “factory upgrade key” which is entered at the HTTP management
screen.
Chapter 5: Operating Modes and Configuration
Telecom
There are five, low-level configuration settings for telecom ports; though, typically, the default settings are
appropriate:
●
E3 vs DS3
●
cable length (for long DS3 runs only)
●
M13 vs C-Bit (for DS3 only)
●
Circuit ID message (for C-Bit only)
●
Transmit clock source
Use a “DS3” configuration setting for North America, Japan, and South Korea; otherwise, “E3” speed.
The cable length setting will transmit a slightly stronger signal on long DS3 coax runs. The M13/C-Bit
setting sets the AIC bit in DS3 frames to either 0 or 1. This bit is typically ignored by the DS3 carrier;
however DS3 carrier equipment set to autosense the incoming DS3 framing type will need this setting to be
correct.
Clock Source
The transmit clock source is typically “local” for both units. Certain DS3/E3 carrier equipment or optical
converters require the same transmit clock in each direction; this may manifest itself as frame-slip errors. In
such a case, set
one
unit to “loop” clock source. In very rare cases the carrier DS3/E3 equipment will
generate the clock for the entire path, and each unit should be set to “loop”. Setting both units to “loop” is
typically inappropriate and can result in transmission failure if a master clock is not being generated by
carrier equipment. Without a master clock, two units set in “loop” mode will wander to an unspecified
clock speed, which is unlikely to meet DS3/E3 specifications.
Dual-channel DS3/E3 units allow Port 2 transmit clock speed to be derived from incoming Port 1 clock
speed. This is an uncommon configuration requirement and should typically be avoided.
In the event of incoming clock loss, the transmit clock will automatically switch to a locally generated
DS3/E3 clock source.
The receive clock speeds are shown at the bottom of the unit's HTTP management statistics page to assist
timing diagnosis.
DS3 Circuit ID PMDL
Firmware since November 2009 allows DS3 Path Maintenance Data Link (PMDL) identification messages
associated with C-Bit framed DS3 links to be received and transmitted if desired. Circuit ID messages
convey human-readable, configurable, physical location information of the DS3 source equipment. These
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