CANOGA PERKINS L351 10/100BASE Media Converter - Manual (Page 22)

EdgeAccess Universal Chassis System
3-4
3.4.3 Link Loss Echo
Caution: To avoid a lockup condition, do not set LLE at both the local and remote ends of the
link.
Link Loss Echo (LLE) propagates a link loss to the device connected to the L351 Extension Port. See
Figure 3-3. If a link loss is detected on the Extension Port Rx, the Extension Port Tx is disabled,
echoing the fault back to the source. LLE configures the L351 to not send data until it receives data.
Set this in the User Interface or at SW3-4 (E). For details on setting SW3, reference Chapter 2.
Figure 3-3. Link Loss Echo Detection
Note: LLE is available only when SBMC is disabled; use LLF when you enable SBMC.
3.4.4 Loopback
The L351 supports four loopback modes that you can set at the local site for both the Local and
Remote L351s. These modes loop the data through either the physical layer (PHY) on the User side
or the FPGA. For details on setting loopback in software, reference Chapter 4.
• Local-Local mode loops the electrical data that the Local L351 receives on the local User Port Rx
through the FPGA to the User Port Tx. The data is not sent out the Extension Port Tx and
incoming data on the Extension Port Rx is ignored. See Figure 3-4. To set this mode at the
Diagnostics screen, set the Loopback State for the Local module to Local.
Figure 3-4. Local-Local Loopback Mode