CTC Union ET100/NRZ, User Manual

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ET100/NRZ LAN-WAN Bridge
Filter:
When this feature is disabled, all frames are passed transparently. In this configuration, the
ET100/NRZ acts as a repeater. When the filter is enabled, frame destinations are tested against the
internal MAC address table. Filtering enabled is the normal selection for Bridging but is usually disabled
when connecting to a switching HUB.
Auto-negotiation:
When this feature is enabled (SW4-6=OFF), the Duplex (SW4-5) and Speed (SW4-4) settings are
ignored and are automatically determined from the LAN connection. When this feature is disabled, the
Duplex and Speed settings of the LAN follow the settings of SW4-4 and SW4-5 and auto MDIX will be
disabled.
Packet Buffer Utilization:
The
ET100/NRZ
contains a 340 packet buffering capacity. When SW4-1 is OFF and SW4-2 is ON,
this buffer is divided equally between LAN to WAN and WAN to LAN packet traffic. When the LAN is
Fast Ethernet and the WAN connection is slow, the buffer may be better utilized by applying a greater
portion to the LAN to WAN packet traffic. In this case, set both SW4-1&2 to OFF. This will provide a 9 to
1 buffer division for LAN to WAN versus WAN to LAN buffer and should increase utilization.
1.7 Clocking Examples
In the following example, the ET100/NRZ is configured for bridging over synchronous NRZ data
signals. One
ET100/NRZ
is configured with an internal clock to facilitate point-to-point application with
another ET100/NRZ. The clock may be set to full 2.048Mbps or may be set to any n x 64 speed formula.
The unit configured for external clock receives timing from the unit providing the NRZ clock. In this
configuration, the rate DIP settings of the external clocked
ET100/NRZ
are ignored.
TD
TC
RD
RC
RD
RC
TD
TC
Internal NRZ Receive
Figure 6: Point to Point, Master (internal) and Slave (receive clock)
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