10 Gigabit Ethernet

10 Gigabit Ethernet (10GE, 10GbE, or 10 GigE) is a group of computer networking technologies for transmitting Ethernet frames at a rate of 10 gigabits per second. It was first defined by the IEEE 802.3ae-2002 standard. Unlike previous Ethernet standards, 10GbE defines only full-duplex point-to-point links which are generally connected by network switches; shared-medium CSMA/CD operation has not been carried over from the previous generations of Ethernet standards so half-duplex operation and repeater hubs do not exist in 10GbE.IEEE 802.3-2012 44.1.1 Scope The first standard for faster 100 Gigabit Ethernet links was approved in 2010.

The 10GbE standard encompasses a number of different physical layer (PHY) standards. A networking device, such as a switch or a network interface controller may have different PHY types through pluggable PHY modules, such as those based on SFP+. Like previous versions of Ethernet, 10GbE can use either copper or fiber cabling. Maximum distance over copper cable is 100 meters but because of its bandwidth requirements, higher-grade cables are required.

The adoption of 10GbE has been more gradual than previous revisions of Ethernet: in 2007, one million 10GbE ports were shipped, in 2009 two million ports were shipped, and in 2010 over three million ports were shipped, with an estimated nine million ports in 2011. , although the price per gigabit of bandwidth for 10GbE was about one-third compared to Gigabit Ethernet, the price per port of 10GbE still hindered more widespread adoption.

In 2017, Apple made built-in 10 Gigabit Ethernet standard in their iMac Pro.

By 2022, the price per port of 10GBASE‑T had dropped to $50–$100 depending on scale. In 2023, Wi-Fi 7 routers began appearing with 10GbE WAN ports as standard.

Standards Over the years the Institute of Electrical and Electronics Engineers (IEEE) 802.3 working group has published several standards relating to 10GbE.

Standard year Description 802.3ae 2002 Ethernet over fiber for LAN (10GBASE-SR), WAN (10GBASE-LR, 10GBASE-ER, 10GBASE-LX4), and SDH/SONET-compatible WAN (10GBASE-SW, 10GBASE-LW, 10GBASE-EW) 802.3ak 2004 10GBASE-CX4 Ethernet over twinaxial cabling 802.3-2005 2005 A revision of base standard incorporating 802.3ae, 802.3ak and errata 802.3an 2006 10GBASE-T Ethernet over copper twisted pair cable 802.3ap 2007 Backplane Ethernet, 1 and over printed circuit boards (10GBASE-KR and 10GBASE-KX4) 802.3aq 2006 10GBASE-LRM Ethernet over multi-mode fiber with enhanced equalization 802.3-2008 2008 A revision of base standard incorporating the 802.3an/ap/aq/as amendments, two corrigenda and errata. Link aggregation moved to 802.1AX. 802.3av 2009 10GBASE-PR Ethernet PHY for EPON 802.3-2015 2015 The previous version of the base standard 802.3bz 2016 2.5 Gigabit and 5 Gigabit Ethernet over Cat-5/Cat-6 twisted pair – 2.5GBASE-T and 5GBASE-T 802.3-2018 2018 The previous version of the base standard 802.3ch 2020 Physical Layer Specifications and Management Parameters for 2.5, 5 and Automotive Electrical Ethernet (10GBASE-T1)802.3-20222022The latest version of the base standard incorporating previous amendments

Physical layer modules

To implement different 10GbE physical layer standards, many interfaces consist of a standard socket into which different physical (PHY) layer modules may be plugged. PHY modules are not specified in an official standards body but by multi-source agreements (MSAs) that can be negotiated more quickly. Relevant MSAs for 10GbE include XENPAK (and related X2 and XPAK), XFP and SFP+. When choosing a PHY module, a designer considers cost, reach, media type, power consumption, and size (form factor). A single point-to-point link can have different MSA pluggable formats on either end (e.g., XPAK and SFP+) as long as the 10GbE optical or copper port type (e.g. 10GBASE-SR) supported by the pluggable is identical.

XENPAK was the first MSA for 10GE and had the largest form factor. X2 and XPAK were later competing standards with smaller form factors. X2 and XPAK have not been as successful in the market as XENPAK. XFP came after X2 and XPAK, and it is also smaller.

The 10-gigabit module standard is the Enhanced Small Form-factor Pluggable transceiver, generally called SFP+. Based on the Small Form-factor Pluggable (SFP) transceiver and developed by the ANSI T11 fibre channel group, it is smaller still and lower power than XFP. SFP+ has become the most popular socket on 10GE systems. SFP+ modules do only optical to electrical conversion, no clock and data recovery, putting a higher burden on the host's channel equalization. SFP+ modules share a common physical form factor with legacy SFP modules, allowing higher port density than XFP and the re-use of existing designs for 24 or 48 ports in a 19-inch rack width blade.

Optical modules are connected to a host by either a XAUI, XFI or SerDes Framer Interface (SFI) interface. XENPAK, X2, and XPAK modules use XAUI to connect to their hosts. XAUI (XGXS) uses a four-lane data channel and is specified in IEEE 802.3 Clause 47. XFP modules use an XFI interface, and SFP+ modules use an SFI interface. XFI and SFI use a single-lane data channel and the 64b/66b encoding specified in IEEE 802.3 Clause 49.

SFP+ modules can further be grouped into two types of host interfaces: linear or limiting. Limiting modules are preferred except for long-reach applications using 10GBASE-LRM modules.

Name Standard Status Media module Reach (m) #(⇆) #(→) #(→) Notes colspan="11" (CL48/71) 1 4 N/A 4 PCBs; (CL49/72) 1 1 1 1 PCBs (CL100-102) 1 1 1 EPON Protocol over Coax (EPoC) – up to downstream and upstream for a passive optical, point-to-multipoint network using passband OFDM with up to 16384-QAM (CL48/54) XENPAK X2XFP 15 4 N/A 4 Data centers; SFP+ 715100 1 1 1 Data centers;Cable types: passive twinaxial (7 m), active (15 m), active optical (AOC): (100 m) rowspan="4" rowspan="4" rowspan="4" rowspan="4" SFP+X2XFP 2 1 1 (CL49/52) rowspan="4" rowspan="4" rowspan="4" SFP+X2XPAKXFP 2 1 1 Modal bandwidth (reach): 160 MHz·km (26 m), 200 MHz·km (33 m),400 MHz·km (66 m), 500 MHz·km (82 m), 2000 MHz·km (300 m),4700 MHz·km (400 m) (CL49/68) rowspan="2" rowspan="2" rowspan="2" SFP+X2 2 1 1 Modal bandwidth: 500 MHz·km OS1 and OS2 up to 300 meter is supported by Cisco and FS, although not specified in the standard. (CL48/53) rowspan="2" rowspan="2" rowspan="2" X2 2 4 4 WDM;Modal bandwidth: 500 MHz·km (CL50/52) rowspan="4" rowspan="4" rowspan="4" SFP+XPAK 2 1 1 WAN;-ZW: -EW with higher performance optics (CL50/52) SFP+XPAK 2 1 1 (CL50/52) rowspan="2" rowspan="2" SFP+ 2 1 1 SFP+X2XPAKXFP 2 1 1 SFP+XFP 1 1 1 10G EPON (CL49/52) rowspan="2" rowspan="2" SFP+X2XFP 2 1 1 -ER with higher performance optics

+Comparison of twisted-pair-based Ethernet physical transport layers (TP-PHYs) Name Standard Status Speed Pairs Lanes per Spectral efficiency Line code Symbol rate per lane (MBd) (MHz) Max (m) Cable Cable rating (MHz) Usage (CL55) 10,000 4 4 6.25 64b/65b PAM-16 128-DSQ, LDPC-FEC 800 400 100 Cat 6A 500 LAN, Data center (CL149) 10,000 1 1 3.5 64b/65b PAM-4 RS-FEC 5,625 2,812.5 15 4,000 Automotive, IoT, M2M

Optical fiber

There are two basic types of optical fiber used for 10 Gigabit Ethernet: single-mode (SMF) and multi-mode (MMF). In SMF light follows a single path through the fiber while in MMF it takes multiple paths resulting in differential mode delay (DMD). SMF is used for long-distance communication and MMF is used for distances of less than 300 m. SMF has a narrower core (8.3 μm) which requires a more precise termination and connection method. MMF has a wider core (50 or 62.5 μm). The advantage of MMF is that it can be driven by a low cost Vertical-cavity surface-emitting laser (VCSEL) for short distances, and multi-mode connectors are cheaper and easier to terminate reliably in the field. The advantage of SMF is that it can work over longer distances.

In the 802.3 standard, reference is made to FDDI-grade MMF fiber. This has a 62.5 μm core and a minimum modal bandwidth of 160 MHz·km at 850 nm. It was originally installed in the early 1990s for FDDI and 100BASE-FX networks. The 802.3 standard also references ISO/IEC 11801 which specifies optical MMF fiber types OM1, OM2, OM3 and OM4. OM1 has a 62.5 μm core while the others have a 50 μm core. At 850 nm the minimum modal bandwidth of OM1 is 200 MHz·km, of OM2 500 MHz·km, of OM3 2000 MHz·km and of OM4 4700 MHz·km. FDDI-grade cable is now obsolete and new structured cabling installations use either OM3 or OM4 cabling. OM3 cable can carry 10 Gigabit Ethernet 300 meters using low cost 10GBASE-SR optics. OM4 can manage 400 meters.IEEE 802.3 52.5 PMD to MDI optical specifications for 10GBASE-S

To distinguish SMF from MMF cables, SMF cables are usually yellow, while MMF cables are orange (OM1 & OM2) or aqua (OM3 & OM4). However, in fiber optics, there is no uniform color for any specific optical speed or technology, with the exception being the angled physical contact connector (APC), being an agreed-upon color of green.

10GBASE-SR

10GBASE-SR ("short range") is a port type for multi-mode fiber and uses 850 nm lasers. Its Physical Coding Sublayer (PCS) is 64b/66b and is defined in IEEE 802.3 Clause 49 and its Physical Medium Dependent (PMD) sublayer in Clause 52. It delivers serialized data at a line rate of .IEEE 802.3 52.1.1.1.2 PMD_UNITDATA.request: When generated

The range depends on the type of multi-mode fiber used.

Fibre type (micrometers) Range (m) FDDI-grade (62.5) 26 OM1 (62.5) 33 OM2 (50) 82 OM3 300 OM4 400

MMF has the advantage over SMF of having lower-cost connectors; its wider core requires less mechanical precision.

The 10GBASE-SR transmitter is implemented with a VCSEL, which is low cost and low power. OM3 and OM4 optical cabling are sometimes described as laser optimized because they have been designed to work with VCSELs. 10GBASE-SR delivers the lowest cost, lowest power and smallest form factor optical modules.

There is a lower cost, lower power variant sometimes referred to as 10GBASE-SRL (10GBASE-SR lite). This is inter-operable with 10GBASE-SR but only has a reach of 100 meters.

10GBASE-LR 10GBASE-LR (long reach) is a port type for single-mode fiber and uses 1310 nm lasers. Its 64b/66b PCS is defined in IEEE 802.3 Clause 49 and its PMD sublayer in Clause 52. It delivers serialized data at a line rate of 10.3125 GBd.

The 10GBASE-LR transmitter is implemented with a Fabry–Pérot or distributed feedback laser (DFB). DFB lasers are more expensive than VCSELs, but their high power and longer wavelength allow efficient coupling into the small core of single-mode fiber over greater distances.

10GBASE-LR maximum fiber length is 10 kilometers, although this will vary depending on the type of single-mode fiber used.

10GBASE-LRM 10GBASE-LRM, (long reach multi-mode) originally specified in IEEE 802.3aq is a port type for multi-mode fiber and uses 1310 nm lasers. Its 64b/66b PCS is defined in IEEE 802.3 Clause 49 and its PMD sublayer in Clause 68. It delivers serialized data at a line rate of 10.3125 GBd.IEEE 802.3 Table 68–3—10GBASE-LRM transmit characteristics 10GBASE-LRM uses electronic dispersion compensation (EDC) for receive equalization.

10GBASE-LRM allows distances up to on FDDI-grade multi-mode fiber and the same 220 m maximum reach on OM1, OM2 and OM3 fiber types. 10GBASE-LRM reach is not quite as far as the older 10GBASE-LX4 standard. Some 10GBASE-LRM transceivers also allow distances up to on standard single-mode fiber (SMF, G.652), however this is not part of the IEEE or MSA specification.IEEE 802.3 68.5 PMD to MDI optical specifications To ensure that specifications are met over FDDI-grade, OM1 and OM2 fibers, the transmitter should be coupled through a mode conditioning patch cord. No mode conditioning patch cord is required for applications over OM3 or OM4.

10GBASE-ER