Ethernet in the first mile

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Ethernet in the first mile (EFM) refers to using one of the Ethernet family of computer network technologies between a telecommunications company and a customer's premises. From the customer's point of view, it is their first mile, although from the access network's point of view it is known as the last mile.

Contents

A working group of the Institute of Electrical and Electronics Engineers (IEEE) produced the standards known as IEEE 802.3ah-2004, which were later included in the overall standard IEEE 802.3-2008. EFM is often used in active optical network deployments. [1]

Although it is often used for businesses, it can also be known as Ethernet to the home (ETTH). One family of standards known as Ethernet passive optical network (EPON) uses a passive optical network.

History

With wide, metro, and local area networks using various forms of Ethernet, the goal was to eliminate non-native transport such as Ethernet over Asynchronous Transfer Mode (ATM) from access networks.

One early effort was the EtherLoop technology invented at Nortel Networks in 1996, and then spun off into the company Elastic Networks in 1998. [2] [3] Its principal inventor was Jack Terry. The hope was to combine the packet-based nature of Ethernet with the ability of digital subscriber line (DSL) technology to work over existing telephone access wires. [4] The name comes from local loop, which traditionally describes the wires from a telephone company office to a subscriber. The protocol was half-duplex with control from the provider side of the loop. It adapted to line conditions with a peak of 10 Mbit/s advertised, but 4-6 Mbit/s more typical, at a distance of about 12,000 feet (3,700 m). Symbol rates were 1 megabaud or 1.67 megabaud, with 2, 4, or 6 bits per symbol. [2] The EtherLoop product name was registered as a trademark in the US and Canada. [5] The EtherLoop technology was eventually purchased by Paradyne Networks in 2002, [6] which was in turn purchased by Zhone Technologies in 2005. [7]

Another effort was the concept promoted by Michael Silverton of using Ethernet variants that used fiber-optic communication to residential as well as business customers. This was an example of what has become known as fiber to the home (FTTH). The Fiberhood Networks company provided this service from 1999 to 2001. [8] [9]

Some early products around the year 2000, were marketed as 10BaseS by Infineon Technologies, although they did not technically use baseband signalling, but rather passband as in very-high-bit-rate digital subscriber line (VDSL) technology. [10] A patent was filed in 1997 by Peleg Shimon, Porat Boaz, Noam Alroy, Rubinstain Avinoam and Sfadya Yackow. [11] Long Reach Ethernet was the product name used by Cisco Systems starting in 2001. [12] It supported modes of 5 Mbit/s, 10 Mbit/s, and 15 Mbit/s depending on distance. [13] [14]

In October 2000 Howard Frazier issued a call for interest on "Ethernet in the Last Mile". [15] At the November 2000 meeting, IEEE 802.3 created the "Ethernet in the First Mile" study group, and on July 16, 2001, the 802.3ah working group. In parallel participating vendors formed the Ethernet in the First Mile Alliance (EFMA) in December 2001 to promote Ethernet subscriber access technology and support the IEEE standard efforts. [16] At an early meeting, the EtherLoop technology was called 100BASE-CU and another technology called EoVDSL for Ethernet over VDSL. [17]

The working group's EFM standard was approved on June 24, 2004, and published on September 7, 2004, as IEEE 802.3ah-2004. In 2005, it was included into the base IEEE 802.3 standard. In 2005, the EFMA was absorbed by the Metro Ethernet Forum. [18]

In early 2006, work began on an even higher-speed 10 gigabit/second Ethernet passive optical network (10G-EPON) standard, ratified in 2009 as IEEE 802.3av. [19] The work on the EPON was continued by the IEEE P802.3bk Extended EPON Task Force, [20] formed in March 2012. The major goals for this Task Force included adding support for PX30, PX40, PRX40, and PR40 power budget classes to both 1G-EPON and 10G-EPON. The 802.3bk amendment was approved by the IEEE-SA SB in August 2013 and published soon thereafter as the standard IEEE Std 802.3bk-2013. [21]

In November 2011, IEEE 802.3 began work on EPON Protocol over Coax (EPoC).

On June 4, 2020, the IEEE approved IEEE 802.3ca which allows for symmetric or asymmetric operation with downstream speeds of 25 Gbit/s or 50 Gbit/s, and upstream speeds of 10 Gbit/s, 25 Gbit/s, or 50 Gbit/s over passive optical networks. [22] [23]

Description

EFM defines how Ethernet can be transmitted over new media types using new Ethernet physical layer (PHY) interfaces:

EFM also addresses other issues, required for mass deployment of Ethernet services, such as operations, administration, and management (OA&M) [25] and compatibility with existing technologies (such as plain old telephone service spectral compatibility for copper twisted pair).

Copper wires

Active fiber optics

Passive optical network

Fiber to the home can use a passive optical network. [26]

Additionally clause 57 defines link-level OA&M, including discovery, link monitoring, remote fault indication, loopbacks, and variable access.

2BASE-TL

2BASE-TL is an IEEE 802.3-2008 Physical Layer (PHY) specification for a full-duplex long-reach point-to-point Ethernet link over voice-grade copper wiring. [27] [28]

Rates and distances

Unlike 10/100/1000 PHYs, providing a single rate of 10, 100, or 1000  Mbit/s, the 2BASE-TL link rate can vary, depending on the copper media characteristics (such as length, wire diameter or gauge, number of pairs if the link is aggregated, amount of crosstalk between the pairs, etc.), desired link parameters (such as desired SNR margin, Power Back-Off, etc.), and regional spectral limitations.

2BASE-TL PHYs deliver a minimum of 2 Mbit/s over distances of up to 2.7 kilometres (8,900 ft), using ITU-T G.991.2 (G.SHDSL.bis) technology over a single copper pair. These PHYs may also support an optional aggregation or bonding of multiple copper pairs, called PME Aggregation Function (PAF).

For a single pair, the minimum possible link bitrate is 192  kbit/s (3 x 64 kbit/s) and the maximum bitrate is 5.7 Mbit/s (89 x 64 kbit/s). On a 0.5 mm wire with 3  dB noise margin and no spectral limitations, the max bitrate can be achieved over distances of up to 1 kilometre (3,300 ft). At 6 kilometres (20,000 ft) the maximum achievable bitrate is about 850 kbit/s.

The throughput of a 2BASE-TL link is lower than the link's bitrate by an average 5%, due to 64/65-octet encoding and PAF overhead; both factors depend on packet size. [29]

10PASS-TS

10PASS-TS is an IEEE 802.3-2008 Physical Layer (PHY) specification for a full-duplex short-reach point-to-point Ethernet link over voice-grade copper wiring.

10PASS-TS PHYs deliver a minimum of 10 Mbit/s over distances of up to 750 metres (2,460 ft), using ITU-T G.993.1 (VDSL) technology over a single copper pair. These PHYs may also support an optional aggregation or bonding of multiple copper pairs, called PME Aggregation Function (PAF).

Details

Unlike other Ethernet physical layers that provide a single rate such as 10, 100, or 1000 Mbit/s, the 10PASS-TS link rate can vary, similar to 2BASE-TL, depending on the copper channel characteristics, such as length, wire diameter (gauge), wiring quality, the number of pairs if the link is aggregated and other factors.

VDSL is a short range technology designed to provide broadband over distances less than 1 km of voice-grade copper twisted pair line, but connection data rates deteriorate quickly as the line distance increases. This has led to VDSL being referred to as a "fiber to the curb" technology, because it requires fiber backhaul to connect with a carrier network over greater distances.

VDSL Ethernet in the first mile services using may be a useful way to standardise functionality on metro Ethernet networks, or potentially to distribute internet access services over voice-grade wiring in multi-dwelling unit buildings. However, VDSL2 has already proven to be a versatile and faster standard with greater reach than VDSL.

See also

Related Research Articles

IEEE 802.3 is a working group and a collection of standards defining the physical layer and data link layer's media access control (MAC) of wired Ethernet. The standards are produced by the working group of Institute of Electrical and Electronics Engineers (IEEE). This is generally a local area network (LAN) technology with some wide area network (WAN) applications. Physical connections are made between nodes and/or infrastructure devices by various types of copper or fiber cable.

<span class="mw-page-title-main">Fast Ethernet</span> Ethernet standards that carry data at the nominal rate of 100 Mbit/s

In computer networking, Fast Ethernet physical layers carry traffic at the nominal rate of 100 Mbit/s. The prior Ethernet speed was 10 Mbit/s. Of the Fast Ethernet physical layers, 100BASE-TX is by far the most common.

<span class="mw-page-title-main">Gigabit Ethernet</span> Standard for Ethernet networking at a data rate of 1 gigabit per second

In computer networking, Gigabit Ethernet is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T, is defined by the IEEE 802.3ab standard. It came into use in 1999, and has replaced Fast Ethernet in wired local networks due to its considerable speed improvement over Fast Ethernet, as well as its use of cables and equipment that are widely available, economical, and similar to previous standards. The first standard for faster 10 Gigabit Ethernet was approved in 2002.

Long Reach Ethernet (LRE) was a proprietary networking protocol marketed by Cisco Systems, intended to support multi-megabit performance over telephone-grade unshielded twisted pair wiring over distances up to 5,000 feet (1.5 km). Supporting such distance ranges, LRE is technically classified as a Metropolitan area network (MAN) technology. Technically the protocol was similar to very-high-bitrate digital subscriber line (VDSL), practically Ethernet over VDSL (EoVDSL).

<span class="mw-page-title-main">Passive optical network</span> Technology used to provide broadband to the end consumer via fiber

A passive optical network (PON) is a fiber-optic telecommunications network that uses only unpowered devices to carry signals, as opposed to electronic equipment. In practice, PONs are typically used for the last mile between Internet service providers (ISP) and their customers. In this use, a PON has a point-to-multipoint topology in which an ISP uses a single device to serve many end-user sites using a system such as 10G-PON or GPON. In this one-to-many topology, a single fiber serving many sites branches into multiple fibers through a passive splitter, and those fibers can each serve multiple sites through further splitters. The light from the ISP is divided through the splitters to reach all the customer sites, and light from the customer sites is combined into the single fiber. Many fiber ISPs prefer this system.

<span class="mw-page-title-main">Metro Ethernet</span> Metropolitan area network based on Ethernet standards

A metropolitan-area Ethernet, Ethernet MAN, carrier Ethernet or metro Ethernet network is a metropolitan area network (MAN) that is based on Ethernet standards. It is commonly used to connect subscribers to a larger service network or for internet access. Businesses can also use metropolitan-area Ethernet to connect their own offices to each other.

Physical medium dependent sublayers or PMDs further help to define the physical layer of computer network protocols. They define the details of transmission and reception of individual bits on a physical medium. These responsibilities encompass bit timing, signal encoding, interacting with the physical medium, and the properties of the cable, optical fiber, or wire itself. Common examples are specifications for Fast Ethernet, Gigabit Ethernet and 10 Gigabit Ethernet defined by the Institute of Electrical and Electronics Engineers (IEEE).

The physical coding sublayer (PCS) is a networking protocol sublayer in the Fast Ethernet, Gigabit Ethernet, and 10 Gigabit Ethernet standards. It resides at the top of the physical layer (PHY), and provides an interface between the physical medium attachment (PMA) sublayer and the media-independent interface (MII). It is responsible for data encoding and decoding, scrambling and descrambling, alignment marker insertion and removal, block and symbol redistribution, and lane block synchronization and deskew.

Fiber to the <i>x</i> Broadband network architecture term

Fiber to the x or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber optic cables are able to carry much more data than copper cables, especially over long distances, copper telephone networks built in the 20th century are being replaced by fiber.

<span class="mw-page-title-main">Ethernet physical layer</span> Electrical or optical properties between network devices

The physical-layer specifications of the Ethernet family of computer network standards are published by the Institute of Electrical and Electronics Engineers (IEEE), which defines the electrical or optical properties and the transfer speed of the physical connection between a device and the network or between network devices. It is complemented by the MAC layer and the logical link layer. An implementation of a specific physical layer is commonly referred to as PHY.

40 Gigabit Ethernet (40GbE) and 100 Gigabit Ethernet (100GbE) are groups of computer networking technologies for transmitting Ethernet frames at rates of 40 and 100 gigabits per second (Gbit/s), respectively. These technologies offer significantly higher speeds than 10 Gigabit Ethernet. The technology was first defined by the IEEE 802.3ba-2010 standard and later by the 802.3bg-2011, 802.3bj-2014, 802.3bm-2015, and 802.3cd-2018 standards. The first succeeding Terabit Ethernet specifications were approved in 2017.

PME Aggregation Function (PAF) is a computer networking mechanism defined in Clause 61 of the IEEE 802.3 standard, which allows one or more Physical Medium Entities (PMEs) to be combined to form a single logical Ethernet link.

The 10 Gbit/s Ethernet Passive Optical Network standard, better known as 10G-EPON allows computer network connections over telecommunication provider infrastructure. The standard supports two configurations: symmetric, operating at 10 Gbit/s data rate in both directions, and asymmetric, operating at 10 Gbit/s in the downstream direction and 1 Gbit/s in the upstream direction. It was ratified as IEEE 802.3av standard in 2009. EPON is a type of passive optical network, which is a point-to-multipoint network using passive fiber-optic splitters rather than powered devices for fan-out from hub to customers.

<span class="mw-page-title-main">Ethernet Alliance</span> Internet working group

The Ethernet Alliance was incorporated in the US state of California in August 2005 and officially launched in January 2006 as a non-profit industry consortium to promote and support Ethernet. The objectives were to provide an unbiased, industry-based source of educational information; to ensure interoperability among disparate, standards-based components and systems; to support the development of standards that support Ethernet technology; and to bring together the Ethernet industry to collaborate on the future of the technology.

<span class="mw-page-title-main">10 Gigabit Ethernet</span> Standards for Ethernet at ten times the speed of Gigabit Ethernet

10 Gigabit Ethernet 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. The first standard for faster 100 Gigabit Ethernet links was approved in 2010.

The Service Interoperability in Ethernet Passive Optical Networks (SIEPON) working group proposed the IEEE 1904.1 standard for managing telecommunications networks.

Terabit Ethernet (TbE) is Ethernet with speeds above 100 Gigabit Ethernet. The 400 Gigabit Ethernet and 200 Gigabit Ethernet standard developed by the IEEE P802.3bs Task Force using broadly similar technology to 100 Gigabit Ethernet was approved on December 6, 2017. On February 16, 2024 the 800 Gigabit Ethernet standard developed by the IEEE P802.3df Task Force was approved.

EPON Protocol over Coax, or EPoC, refers to the transparent extension of an Ethernet passive optical network (EPON) over a cable operator's hybrid fiber-coax (HFC) network. From the service provider's perspective the use of the coax portion of the network is transparent to EPON protocol operation in the optical line terminal (OLT) thereby creating a unified scheduling, management, and quality of service (QoS) environment that includes both the optical and coax portions of the network. The IEEE 802.3 Ethernet Working Group initiated a standards process with the creation of an EPoC Study Group in November 2011. EPoC adds to the family of IEEE 802.3 Ethernet in the First Mile (EFM) standards.

25 Gigabit Ethernet and 50 Gigabit Ethernet are standards for Ethernet connectivity in a datacenter environment, developed by IEEE 802.3 task forces 802.3by and 802.3cd and are available from multiple vendors.

IEEE 802.3bz, NBASE-T and MGBASE-T are standards released in 2016 for Ethernet over twisted pair at speeds of 2.5 and 5 Gbit/s. These use the same cabling as the ubiquitous Gigabit Ethernet, yet offer higher speeds. The resulting standards are named 2.5GBASE-T and 5GBASE-T.

References

  1. ↑ Wang, K.; Mas Machuca, C.; Wosinska, L.; Urban, P. J.; Gavler, A.; Brunnström, K.; Chen, J. (2017). "Techno-Economic Analysis of Active Optical Network Migration Toward Next-Generation Optical Access". Journal of Optical Communications and Networking. 9 (4): 327. doi:10.1364/JOCN.9.000327. S2CID   18604241.
  2. 1 2 Patrick H. Stanley (January 8, 2001). "Robust Ethernet in the First Mile" (PDF). Elastic Networks, Inc. Retrieved August 15, 2011.
  3. ↑ Laura Kujubu (April 6, 1998). "Nortel forms EtherLoop group". InfoWorld. p. 46. Retrieved August 15, 2011.
  4. ↑ Bob Metcalfe (March 9, 1998). "Nortel combines best of DSL with best of Ethernet for 10Mbps Internet access". InfoWorld. p. 139. Retrieved August 15, 2011.
  5. ↑ "EtherLoop, Serial Number: 75560747". US Patent and Trademark office. September 28, 1998. Retrieved August 15, 2011.
  6. ↑ "Paradyne Gets Elastic". Light Reading news release. December 28, 2001. Retrieved August 15, 2011.
  7. ↑ "Elastic Networks Elite Modem Installation Guide" (PDF). Elastic Networks, Inc. November 1999. Retrieved August 15, 2011.
  8. ↑ "Fiberhood Networks". company web site. Archived from the original on September 22, 2001. Retrieved August 16, 2011.
  9. ↑ Michael Silverton (March 3, 2001). "Ethernet in the first mile" (PDF). Retrieved August 16, 2011.
  10. ↑ "Infineon's Octal-10BaseS Ethernet over QAM-VDSL Selected by Telson I&C to Enable Broadband Access in Nationwide Korean MTU/MDU Deployment". News release. Infineon Technologies AG. July 2, 2002. Archived from the original on April 13, 2014. Retrieved August 27, 2011.
  11. ↑ "Infineon Strengthens Leadership in MDU/MTU Market with Ethernet over VDSL Technology Patent Award". News release. Infineon Technologies AG. January 8, 2001. Archived from the original on April 13, 2001. Retrieved August 27, 2011.
  12. ↑ "Infineon Announces Second Quarter Results". News release. Infineon Technologies. April 24, 2001. Retrieved August 28, 2011. ...strategic design-win with Cisco for new long range Ethernet products incorporating Infineon?'s 10BaseS? technology
  13. ↑ "Cisco Long-Reach Ethernet Solution" (PDF). Cisco Systems, Inc. May 22, 2002. Retrieved August 27, 2011.
  14. ↑ James Evans (February 20, 2001). "Cisco Offers New Long-Reach Ethernet: No new wiring needed; system uses existing phone lines". PC World. Archived from the original on January 20, 2010. Retrieved August 28, 2011.
  15. ↑ Howard Frazier (October 12, 2000). ""Ethernet in the Last Mile" Call for Interest". IEEE 802.3. Retrieved August 6, 2011.
  16. ↑ "Extreme Launches Ethernet Alliance". Light Reading news release. December 11, 2001. Retrieved August 15, 2011.
  17. ↑ Hugh Barrass (July 9, 2001). "EFM Copper Objective" (PDF). IEEE 802.3. Retrieved August 28, 2011.
  18. ↑ "MEF Absorbs EFMA". Light Reading news release. March 8, 2005. Retrieved August 15, 2011.
  19. ↑ "10Gb/s Ethernet Passive Optical Network". official working group web site. IEEE 802. Retrieved August 6, 2011.
  20. ↑ "IEEE P802.3bk Extended EPON Task Force".
  21. ↑ IEEE Std 802.3bk-2013, IEEE Standard for Ethernet - Amendment 1: Physical Layer Specifications and Management Parameters for Extended Ethernet Passive Optical Networks. IEEE. 2013. Archived from the original on December 17, 2013.
  22. ↑ "IEEE 802.3ca-2020 - IEEE Standard for Ethernet Amendment 9". IEEE. 2020-07-03.
  23. ↑ Knittle, Curtis (2020-07-23). "25G/50G-EPON Standard Crosses the Finish Line – Enhancing Fiber Deployments as Part of Cable's 10G Platform". CableLabs.
  24. ↑ Gerry Pesavento (July 9, 2001). "Point to Multipoint Ethernet Passive Optical Network (EPON)" (PDF). IEEE 802.3. Retrieved August 28, 2011.
  25. ↑ Yaakov (Jonathan) Stein (2006). "Ethernet OAM" (PDF). White paper. RAD Data Communications Ltd. Retrieved August 6, 2011.
  26. ↑ "FTTH Council - Definition of Terms" (PDF). FTTH Council. January 9, 2009. Archived from the original (PDF) on September 24, 2017. Retrieved September 1, 2011.
  27. ↑ IEEE 802.3ah – Ethernet in the First Mile Task Force archive
  28. ↑ "Metro Ethernet Forum". Archived from the original on 2014-04-10. Retrieved 2014-04-17.
  29. ↑ Philip Golden; Herve Dedieu; Krista S. Jacobsen, eds. (2008). "Table 13.6". Implementation and Applications of DSL Technology. Auerbach Publications. ISBN   978-0849334238.

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