SFP+ Direct Attach or SFP+ DAC, as the name implies, uses SFP+ MSA and the inexpensive copper twinax cable with SFP+ connectors on both sides, provides 10G Ethernet connectivity between devices with SFP+ interfaces, which make itself a cost-effective solution for 10G network application. But SFP+ Direct Attach has a limited link distance within 10 meter. thus the target application is interconnection of top-of-rack switches with application servers and storage devices in a rack. Many vendors offer 10G SFP+ Direct Attach cables, today’s article will first talk about two HP SFP+ DAC cables—JD097C and JD095C, then move on to the further illustration of the 10G SFP+ DAC cables.
HP JD097C and JD095C
They are both HP DAC cables, JD097C is HP 10G SFP+ passive Direct Attach copper twinax cable with a link length of 3m, and JD095C has the same specification with the JD097C but with a shorter link distance of 0.65m. Table 1 shows the models of HP 10G SFP+ DAC cables. For the detailed information about SFP+ DAC cables, please read on.
10 Gigabit Ethernet and Copper Cabling Choices
As switching standards mature and copper cabling standards catch up, the use of copper cabling for 10GbE is becoming more common. Currently, there are three different copper cabling technologies for 10 Gigabit Ethernet, each with different price and performance capabilities (see Table 2). Although fiber (SFP+ optics) delivers the lowest latency, many IT departments use copper cabling for switch-to-switch or switch-to-server Connections.
10GBase-CX4, published in 2004, was the first 10 Gigabit Ethernet copper standard. CX4 was relatively economical and allowed for very low latency. Its disadvantage was a too-large form factor for high density port counts in aggregation switches. SFP+ is the latest standard for optical transceivers. 10G SFP+Cu Direct Attach Cables (DAC) connect directly into an SFP+ housing. This new copper solution has become the connectivity of choice for servers and storage devices in a rack because of its low latency, small form factor, and reasonable cost. 10GBase-T or IEEE 802.3an-2006 was released in 2006 to run 10 Gigabit Ethernet over CAT6a and CAT7 copper cabling up to 100 meters. While promising, 10GBase-T still needs technology improvements to lower its cost, power consumption, and latency.
Direct Attach Cables are Convenient for Short Runs
10G SFP+ Direct Attach is a copper interconnect using a passive twinax cable assembly that connects directly into an SFP+ housing. It has a range of 10 meters and like 10GBASE-CX4, is low power, low cost and low latency with the added advantage of having the small form factor of SFP+, and smaller, more flexible cabling. Figure 3 shows the basic components of 10G network.
SFP+ Direct Attach cables integrate SFP+ compatible connectors with a copper cable into a low-latency, energy-efficient, and low-cost solution. DAC are available in several lengths up to 10 meters (33 ft) and are the currently the best cabling option for short 10 Gigabit Ethernet connections.
Top-of-Rack (ToR) switches use the SFP+ form factor to provide high port density 10 Gigabit Ethernet in an efficient 1U form factor. Server and network storage vendors use 10 Gigabit SFP+ network adapters on their equipment for the same reason. DAC simplify rack cabling and termination. Each server and network storage device can be directly connected to the ToR switch, eliminating the need for intermediate patch panels. DAC are flexible enough for vertical cabling management within the rack architecture. The only cabling outside the rack is the ToR switch uplink connection to the aggregation layer, making moving racks easy.
The SFP+ interfaces enables mass migration of the 1GbE network to 10GbE by offering a very low cost 10G SFP+ (direct attached copper cable assembly) option for short reach interconnects along with multimode and single-mode fiber options. The SFP+ interface accepts along with hot-pluggable, small-footprint, optical transceivers, a Direct Attach Cable, which replaces two optical modules and a connectorized optical fiber with a twinax copper cable assembly. Fiberstore offers third-party SFP+ DAC cables including the above HP JD097C and JD095C. These compatible SFP+ interfaces are tested in prior to shipping to ensure its high quality and compatibility. If you have any requirement of our products, please send your request to us.