DOM — A Fiber Tester Inside Your SFPs

When reading parameters of an SFP transceiver, you may see words like "DOM". Do you know what's the meaning of "DOM"? And why should an SFP transceiver be with DOM? In this post, some detailed information about DOM will be given.

What Is DOM?

DOM, short for digital optical monitoring, is used to monitor some parameters of the transceiver in real-time, helping to identify the location of the fiber link failure, simplify maintenance, and improve system reliability. DOM allows you to monitor the TX (transmit) and RX (receive) power of the module, temperature, and transceiver supply voltage. You can configure your device to monitor optical transceivers in the system, either globally or by specified port. When this feature is enabled, the system monitors the temperature and signal power levels for the optical transceivers in the specified ports. Console messages and syslog messages are sent when optical operating conditions fall below or rise above the SFP manufacturer's recommended thresholds. With DOM, network administrators can check and ensure that the module is functioning correctly in an easy and convenient way. This is why most of modern optical SFP transceivers support DOM functions. The following image shows a Brocade E1MG-SX-OM compatible 1000BASE-SX SFP DOM transceiver. With DOM function, it is able to assist network designers in detecting and digitizing parameter signals on circuit board inside the SFP module.

How to Use DOM?

To ensure the DOM capability function well, both the device and the platform must support the feature. When the transceiver module is DOM-enabled, a minimum software version may be required to support the feature in each platform. There are some restrictions of using DOM. Ensure that your optical transceiver supports DOM; specifies the time interval for monitoring optical transceivers; in case of combo ports with SFP and RJ45 provision, when SFP is inserted in slot or port and media type is not configured to SFP, DOM is functional only if global transceiver monitoring is enabled.

SFP Transceivers with DOM

With the popularity of DOM function, there are many SFP transceivers are with DOM, like 1000BASE-LX SFP DOM transceiver, 1000BASE-SX SFP DOM transceiver, 1000BASE-LX SFP DOM transceiver, 1000BASE-EX SFP DOM transceiver, and 1000BASE-ZX SFP DOM transceiver. And there are many third-party optical transceiver include the DOM functionality. What should be mentioned here is that although optical transceivers with DOM are much popular than those without DOM, some user still use the older optical transceivers in consideration of the upgrading costs.

Conclusion

SFP transceivers with DOM help to ensure that the business can be proactive in preventative maintenance of the network and ensure business continuity. And it would easy to explain why modern transceivers are with DOM. It is an irresistible development trend of industry and technology. Fiberstore is a professional optical transceiver manufacturer and supplier, which offers a with varity of compatible SFP transceivers with DOM functionality with a low cost. For example, Allied Telesis AT-SPSX compatible 1000BASE-SX SFP DOM transceiver costs only $6.00, and NETGEAR AGM732F compatible 1000BASE-LX SFP DOM transceiver costs only $7.00.