The dramatic growth in business data throughput has led to an increased use and demand for high performing interconnects, storage devices and servers. The result is an increased expansion of higher speed Ethernet solutions, specifically 10 Gigabit Ethernet (10GbE). However, due to the lack of complete backward compatibility with previous Ethernet technologies, there is some confusion on the cables and connectors required for 10GbE.
The basic cable types available for your 10GbE applications are copper and fiber-optic cables. With increased interface speeds, you should expect a rise in fiber-optic cable and connector use.
On the other hand, higher Gigabit speeds mean copper cables and interconnects suffer too much amplitude, apart from uses in short distance applications, like to a nearby rack or within a rack. The amplitude loss is, in some cases, called poor signal to noise ratio or just too noisy.
In general, fiber optic cable options on the market are:
- Single-mode fiber (SMF) – The cabling features an optical core of about 9 microns, lower modal dispersion compared to multi-mode fiber and supports distances of up to 100 Km depending on transceivers, transmission speed and buffer credits for allocated switches.
- Multi-mode fiber (MMF) – This cabling option has a core of either 50 or 62.5 microns, supporting distances of up to 600 meters, depending on the transceivers used and transmission speeds.
The most common fiber-optic 10GbE cable on the market is the 10GBase-SR cable that is capable of supporting an SFP+ connector in combination with a 10G transmission-rated optical transceiver. Long reach fiber optic cables or 10GBASE-LR support single-mode fiber optic cables and connectors.
In addition, indoor fiber-optic cables are suitable for using in indoor building applications and they are fire-retardant, reducing the number of connections and transition splices required. Outdoor cables (Outside Plant or OSP) are designed for outdoor applications. The latter fiber-optic cables are water (freezing and liquid) resistant as well as ultra-violet resistant.
The most common copper 10GbE cable is the 10GBase-CR, which uses the standard SFP+ connector, sometimes known as Direct Attach Copper (DAC). The connector fits into the same form factor connector and housing as fiber-optic cables with SFP+ connectors. Most 10G switches on the market also accept SFP+ connectors, offering support for both fiber-optic and copper cables.
10GBase-CR cables are typically available in lengths of 1m, 3m, 5m, 7m, 8.5m and even longer. However, the most common cables cover 3m and 5m.
Passive copper connections are compatible with many interfaces, but as transfer rates increase, passive copper does not provide the required distance, while taking up too much physical space. To overcome this, businesses are fast moving towards active copper type interfaces that provide higher speed connections. Such active copper connections feature components that help in boosting signal, reduce noise and with even smaller gauge cables for improved signal distance, airflow and cable flexibility.
10GBase-T cables and connectors look like, but are not the same as those used in 1000Base-T options. The 10GBase-T cables are often Cat6a (Class EA) cables that support higher frequencies in 10GbE transmission in applications that require a distance of up to 100 meters. However, you need to ensure that the cables are certified for at least 500MHz for 10GBase-T compliance.
Fortunately, you can use several different connectors with 10GbE cables. Every connector type has its specific lane numbers or channels. Since 2011, the fastest connector speeds supported are 10Gigabits per second per lane.
The different types of connectors you can use are:
- Copper (CX4) – These connectors feature 4 lanes with 5Gbps maximum speed per lane and 20Gbps maximum speed in total. The connector is usually used by copper cable type connections with 10GbE output.
- Small form-factor pluggable enhanced (SFP+) – The connectors make use of a single lane with 16Gbps maximum speed. The connector is common in copper and fiber-optic cable types for transmission of 10GbE networks.
When Should You Use the Different Cables?
When you need to cover short distances like within a rack or to a nearby rack, it is best to use DAC with SFP+ connectors (10Gbase-CR). For middle-range distances, use laser optimized multi-mode fiber (LOMMF) cables like OM3 and OM4 with SFP+ connectors. For longer distances, make use of single-mode fiber-optic (OS1) cables (10Gbase-LR).
Bonus tip: If your Ethernet switch infrastructure and network adapter is capable of supporting 10Gbase-T (RJ45) cables and connectors, you are better off implementing Cat6a and Cat6 networking cables in your office.
10GbE networking makes streaming and sharing of files over your local business network much easier, faster and efficient. To build a 10G business network, you require 10G core switches, access switches with 10G-uplink capability and 10G network interface cards for your storage and server devices. In addition, you also need the right cable, which is mostly determined by the switch in your environment.