User`s manual

Chapter 1 Overview
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the secondary clock source to the primary one. Therefore, different sources
must be configured for the primary and secondary clocks.
 Locked to a recovered clock (RX clock option). The reference source of the
recovered clocks can be selected in accordance with the desired method of
clock dissemination in the user’s network:
 RX SDH – reference source locked to the receive clock recovered from
the line signal by the STM-1 interface. This timing mode is also called
loopback timing. Either Optical1 or Optical2 can be selected for RX SDH.
The SDH timing of the MUXpro units can be locked to the highly accurate
master clock of the SDH network.
 RX E1 – reference clock locked to the receive clock recovered from the
E1 line signal received by the desired E1 interface. This timing mode is
also called external timing. One of E1 ports can be selected for RX E1.
MUXpro820 provides E1 port 1 to E1 port 8. MUXpro8216 provides E1
port 1 to E1 port 16.This timing mode can enable locking the SDH timing
of the MUXpro units used in a private network to the timing of the E1
network.
 Internal clock: The internal oscillator of MUXpro units provides the timing
reference(accuracy+4.6ppm) for MUXpro units used in a private network
1.6.7.2 Output clock
Output clock is used as reference source for the far end. One of E1 ports can be
selected for Output clock. MUXpro820 provides E1 port 1 to E1 port 8.
MUXpro8216 provides E1 port 1 to E1 port 16. All clock options described above
may be used as Output clock (2048Kb/sec) to the far end.
1.6.8 Management Subsystem
1.6.8.1 Firmware Updating
The operation of the MUXpro management subsystem and of its other circuits is
determined by software stored in flash memory.
The firmware can be updated using TFTP through any of the management access
options described above. Using remote downloading enables network operators to
distribute software from a central location rapidly and efficiently. However, other