In the past few decades, the Ethernet industry has been working on providing solutions to increase the speed of Ethernet from 1 to 10 gigabits per second. For enterprise LAN applications, 10 Gigabit Ethernet enables network managers to scale their Ethernet networks from 10 Mbps to 10,000 Mbps, while leveraging their investments in Ethernet as they increase their network performance. There are various types of cables and transceivers available for making Ethernet connections at speeds of 10 Gigabit per second. This article will introduce both the copper and fiber connectivity options for 10 Gigabit Ethernet.
Standards bodies initially offered several options for the 10-Gigabit transceiver. The one that ultimately evolved as most popular in commercial data center usage was the XFP transceiver. In recent years an extension of the SFP transceiver was standardized for use with 10 Gigabit Ethernet and named SFP+. SFP+ has three outstanding advantages. First of all, it was smaller than the XFP form factor allowing for much more dense packaging of ports on (primarily) switches. Secondly, a new type of very short distance copper cable was developed which uses the same mechanical form factor as the optical transceiver and is capable of carrying 10Gbps Ethernet data. This cable type is called direct attach copper cable which will be introduced later. SFP+ has now become the predominant 10G Ethernet connector type. (The following picture shows Cisco SFP-10G-SR-X compatible 10GBASE-SR/SW SFP+ transceiver).
Fiber cables consist of the cable itself and the connectors on the ends. There are multiple choices for cable type and for connector type. The difference in cable choices come from the distance limitations encountered with the various types of optical transmission. The commonly available types of fiber cables include: SR for connections of up to 300 m in length, LR for connections of up to 2 km in length and ER for connections of up to 10 km in length.
- 10GBASE-T For 10-Gigabit Ethernet cabling, the standards body determined that even enhanced Cat5e UTP traditional Ethernet cable would not be able to carry the signal reliably for any significant distance. So a new specification which still uses RJ45 connectors was introduced and is commonly referred to by its standards name 10GBASE-T. It calls for a 4-wire twisted pair cable with even more strinent limitations on cross-talk.
- CX4 CX4 is a cable type generally associated with an alternative networking technology called InfiniBand. CX4 cable can also be used in 10Gigabit Ethernet connections. It uses a coaxial copper cable and can support cable lengths of up to 15m.
- SFP+ As discussed above, one of the advantages of the SFP+ connector type was that a new type of very-short-distance copper cable was developed which uses the same mechanical form factor as the optical transceiver and is capable of carrying 10Gbps Ethernet data. This cable type namely SFP+ direct attach copper cable is a fixed assembly that is purchased at a given length, with the SFP+ connector modules permanently attached to each end of the cable. For instance, the following Brocade 10G-SFPP-TWX-0101 compatible 10G SFP+ direct attach copper cable is terminated with one SFP+ connector on each end of the cable. It provides high performance in 10 Gigabit Ethernet network applications, using an enhanced SFP+ connector to send 10 Gbps data through one paired transmitters and receivers over a thin twinax cable.
The deployment of 10GbE infrastructure should be much easier, with these media options in mind, coupled with your own such project considerations as cost, power consumption and distance reach. 10 Gigabit Ethernet has become the technology of choice for enterprise, metropolitan, and wide area networks. Choosing the right kind of connectivity options helps you ensure the proper and right performance of your networks.