XFP 10G Direct-Attach Cable Flapping
This is quite a common problem with 10G XFP Transceivers. Link is flapping UP/DOWN/UP/DOWN … In this case, it is with an XFP 10G DAC cable.
As we know, the XFP optical transceiver specification was published in 2002, but the SFP+ optical transceiver's first publication was in 2006. This means that XFP modules have been in business for a lot more time than SFP+ modules. These roughly four years are a lot of time for technologies to develop, as, for example, network devices like routers and switches have adopted a lot of new functionality during these years.
The problem happens because there are older devices (switches, routers) that support XFP modules and newer devices that support SFP+ and XFP modules. The main difference between XFP and SFP+ modules is their form factor. XFP is slightly larger. This difference in size is because of fact the XFP transceiver has a built-in clock and data recovery (CDR) chip. On the contrary, SFP+ modules do not have this CDR chip built in. The newer network devices, like switches, have a built-in CDR chip in the upstream ASIC or in a special chip called – signal conditioning chip.
XFP 10G DAC cables differ. There are Active (with CDR compensation) and Passive (without CDR compensation) XFP 10G DAC cables. Active type cables have a built-in CDR chip in transceivers, whereas Passive they don’t. As a result Passive technology DAC cable can be used only in newer type of network devices, which provides the CDR function by themselves. Older network devices which does not have a CDR chip on their platform must use Active XFP 10G DAC cables, which have a built-in CDR chip.
This is the reason for the problem. The Passive type XFP 10G DAC cable is used in older types of equipment which does not have a CDR chip on board. As a result, CDR is not being implemented, and received and sent signals are getting out of phase, which leads to a flappy link. To evade this problem, choose the correct XFP 10G DAC cable wisely!
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10G XFP Transceivers
EDGEOPTIC XFP transceivers deliver reliable 10 Gigabit connectivity for networks requiring XFP form factor compatibility. While newer SFP+ modules dominate modern deployments, extensive XFP-based infrastructure continues operating globally, demanding quality replacement modules and expansion options. Our comprehensive portfolio spans from 300m multimode to 110km single-mode reach, encompassing standard duplex, BiDi single-fiber, CWDM/DWDM wavelength-multiplexed, and industrial-temperature variants. Each transceiver undergoes rigorous testing ensuring compatibility across 80+ equipment manufacturers. Whether maintaining critical legacy systems or expanding existing XFP infrastructure, our modules provide proven performance with comprehensive MSA compliance.
Direct Attach Cables (DAC) – 10G to 800G
Direct Attach Copper (DAC) cables deliver high-speed connectivity for data centers and network equipment rooms where cost efficiency and low power consumption are priorities. These pre-terminated copper assemblies eliminate the need for separate transceivers, reducing both equipment costs and power draw compared to optical solutions. EdgeOptic's DAC portfolio spans 10G to 800G speeds, with passive cables reaching up to 7 meters for lower speeds and 3 meters for higher bandwidths. For connections requiring extended reach without transitioning to fiber, our active DAC options provide signal amplification to maintain data integrity over longer distances. When connecting equipment operating at different speeds—such as 100G switches to 25G servers or 40G infrastructure to 10G devices—our breakout DAC cables split high-bandwidth connections into multiple lower-speed ports, simplifying network architecture and reducing port costs. All EdgeOptic DAC cables are coded for compatibility with major networking vendors including Cisco, Juniper, HPE, Dell, and Mellanox. Our engineering team can also provide custom configurations with different vendor coding on each end—ideal for mixed-vendor environments in data center deployments. Contact us for compatibility questions or custom requirements.