When using SFP transceiver modules, you will often need to know it is with DDM (digital diagnostics monitoring) functions or not, many peoples don’t know well about this term, this article will introduce three roles that DDM plays. DDM gives the end user the ability to monitor real-time parameters of the SFP, such as optical output power, optical input power, temperature, laser bias current, and transceiver supply voltage.
Optical module life prediction
DDM allows network managers to find potential link failures before system performance is affected. Failure notice, the system administrator can switch the business to a backup link or replace the suspicious device, so as to repair the system in the case of uninterrupted business.
Through real-time monitoring of the internal operating voltage and temperature of the transceiver module allows the system administrator to find some potential problems:
Vcc voltage is too high, will bring about the breakdown of CMOS devices; Vcc voltage is too low, the laser does not work properly.
Received power is too high, damage to the receiving module.
Operating temperature is too high, will accelerate the aging of the device.
In addition, the monitoring of the received optical power, can monitor the performance of the lines and the remote transmitter.
In optical link, locating the fault occurred fast loading of business is essential. ault isolation characteristics allows system administrators to quickly locate the position of a link failure.
This feature can locate the fault in module on the line; locally module or modules in the remote. Quickly locate the fault, reducing the time to repair the system.
Another function of DDM is to verify the modules compatibility. Compatibility verification is the analysis of the modules work environment to meet the data sheet or compatibility and related
standards. The performance of the module only in this compatibility work environment can be guaranteed. In some cases, due to environmental parameters beyond the data sheet or standard, will cause
the module performance degradation, thereby result in the transmission error.
Environment like below is not compatible with the modules:
Voltage exceed the specified range
The received optical power is overload or lower than the receiver sensitivity.
Temperature is beyond the standard operating temperature range.
Ingellen Technology, as one of major fiber optic transceiver OEM manufacturers in China, provides a full range of SFP transceivers with or without DDM functions. Besides, you can also wholesale Cisco transceivers which are with 100% compatibilities to all you Cisco equipments. We provide high quality compatible transceivers for Cisco, HP, 3Com, Juniper, Foundry, etc.