Heterogeneous network

Last updated

In computer networking, a heterogeneous network is a network connecting computers and other devices where the operating systems and protocols have significant differences. For example, local area networks (LANs) that connect Microsoft Windows and Linux based personal computers with Apple Macintosh computers are heterogeneous. [1] [2]

Contents

Heterogeneous network also describes wireless networks using different access technologies. For example, a wireless network that provides a service through a wireless LAN and is able to maintain the service when switching to a cellular network is called a wireless heterogeneous network.[ citation needed ]

HetNet

Reference to a HetNet often indicates the use of multiple types of access nodes in a wireless network. A Wide Area Network can use some combination of macrocells, picocells, and femtocells in order to offer wireless coverage in an environment with a wide variety of wireless coverage zones, ranging from an open outdoor environment to office buildings, homes, and underground areas. Mobile experts define a HetNet as a network with complex interoperation between macrocell, small cell, and in some cases WiFi network elements used together to provide a mosaic of coverage, with handoff capability between network elements. [3] A study from ARCchart estimates that HetNets will help drive the mobile infrastructure market to account for nearly US$57 billion in spending globally by 2017. [4] Small Cell Forum defines the HetNet as ‘multi-x environment – multi-technology, multi-domain, multi-spectrum, multi-operator and multi-vendor. It must be able to automate the reconfiguration of its operation to deliver assured service quality across the entire network, and flexible enough to accommodate changing user needs, business goals and subscriber behaviours.’ [5]

HetNet architecture

From an architectural perspective, the HetNet can be viewed as encompassing conventional macro radio access network (RAN) functions, RAN transport capability, small cells, and Wi-Fi functionality, which are increasingly being virtualized and delivered in an operational environment where span of control includes data center resources associated with compute, networking, and storage. [6]

In this framework, self-optimizing network (SON) functionality is essential to enable order-of-magnitude network densification with small cells. Self-configuration or ‘plug and play’ reduces time and cost of deployment, while self-optimization then ensures the network auto-tunes itself for maximum efficiency as conditions change. Traffic demand, user movements and service mix will all evolve over time, and the network needs to adapt to keep pace. These enhanced SON capabilities will therefore need to take into account the evolving user needs, business goals and subscriber behaviors.[ citation needed ]

Importantly, functions associated with HetNet operations and management take earlier SON capability that may have only been targeted at a single domain or technology, and expand it to deliver automated service quality management across the entire HetNet. [7]

Wireless

A Heterogeneous wireless network (HWN) is a special case of a HetNet. Whereas a HetNet may consist of a network of computers or devices with different capabilities in terms of operating systems, hardware, protocols, etc., a HWN is a wireless network that consists of devices using different underlying radio access technology (RAT). [8]

Several problems still need to be solved in heterogeneous wireless networks such as:

An HWN has several benefits when compared with a traditional homogeneous wireless network, including increased reliability, improved spectrum efficiency, and increased coverage. Reliability is improved since when one particular RAT within the HWN fails, it may still be possible to maintain a connection by falling back to another RAT. Spectrum efficiency is improved by making use of RATs, which may have few users through the use of load balancing across RATs and coverage may be improved because different RATs may fill holes in coverage that any one of the single networks alone would not be able to fill.[ citation needed ]

Semantics

From a semantic point of view, it is very important to note that the heterogeneous network terminology can have different connotations in wireless telecommunications. For instance, it could refer to the paradigm of seamless and ubiquitous interoperability between various multi-coverage protocols (aka, HetNet). Otherwise, it might refer to the non-uniform spatial distribution of users or wireless nodes (aka, spatial inhomogeneity). Therefore, using the term "heterogeneous network" without putting it into context can result in a source of confusion in scientific literature and during the peer-review cycle. In fact, the confusion may further be aggravated, especially in light of the fact that the HetNet paradigm is often also researched from a geometrical angle. [15]

See also

Related Research Articles

<span class="mw-page-title-main">Wireless network</span> Network not fully connected by cables

A wireless network is a computer network that uses wireless data connections between network nodes.

<span class="mw-page-title-main">Wi-Fi</span> Wireless local area network

Wi-Fi is a family of wireless network protocols based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves. These are the most widely used computer networks in the world, used globally in home and small office networks to link desktop and laptop computers, tablet computers, smartphones, smart TVs, printers, and smart speakers together and to a wireless router to connect them to the Internet, and in wireless access points in public places like coffee shops, hotels, libraries, and airports to provide visitors with Internet connectivity for their mobile devices.

<span class="mw-page-title-main">Wireless</span> Transfer of information or power that does not require the use of physical wires

Wireless communication is the transfer of information (telecommunication) between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most common wireless technologies use radio waves. With radio waves, intended distances can be short, such as a few meters for Bluetooth or as far as millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mouse, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Somewhat less common methods of achieving wireless communications involve other electromagnetic phenomena, such as light and magnetic or electric fields, or the use of sound.

<span class="mw-page-title-main">Beam tilt</span> Aiming of an antenna radiation pattern below the horizontal plane

Beam tilt is used in radio to aim the main lobe of the vertical plane radiation pattern of an antenna below the horizontal plane.

<span class="mw-page-title-main">WiMAX</span> Wireless broadband standard

Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options.

<span class="mw-page-title-main">Wireless mesh network</span> Radio nodes organized in a mesh topology

A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. It can also be a form of wireless ad hoc network.

A cognitive radio (CR) is a radio that can be programmed and configured dynamically to use the best wireless channels in its vicinity to avoid user interference and congestion. Such a radio automatically detects available channels in wireless spectrum, then accordingly changes its transmission or reception parameters to allow more concurrent wireless communications in a given spectrum band at one location. This process is a form of dynamic spectrum management.

<span class="mw-page-title-main">Orthogonal frequency-division multiple access</span> Multi-user version of OFDM digital modulation

Orthogonal frequency-division multiple access (OFDMA) is a multi-user version of the popular orthogonal frequency-division multiplexing (OFDM) digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users. This allows simultaneous low-data-rate transmission from several users.

<span class="mw-page-title-main">Comparison of mobile phone standards</span>

This is a comparison of standards of mobile phones. A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1979 and the early to mid-1980s.

A wireless ad hoc network (WANET) or mobile ad hoc network (MANET) is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers or wireless access points. Instead, each node participates in routing by forwarding data for other nodes. The determination of which nodes forward data is made dynamically on the basis of network connectivity and the routing algorithm in use.

<span class="mw-page-title-main">Femtocell</span> Small, low-power cellular base station

In telecommunications, a femtocell is a small, low-power cellular base station, typically designed for use in a home or small business. A broader term which is more widespread in the industry is small cell, with femtocell as a subset. It connects to the service provider's network via broadband ; current designs typically support four to eight simultaneously active mobile phones in a residential setting depending on version number and femtocell hardware, and eight to sixteen mobile phones in enterprise settings. A femtocell allows service providers to extend service coverage indoors or at the cell edge, especially where access would otherwise be limited or unavailable. Although much attention is focused on WCDMA, the concept is applicable to all standards, including GSM, CDMA2000, TD-SCDMA, WiMAX and LTE solutions.

<span class="mw-page-title-main">Mobile broadband</span> Marketing term

Mobile broadband is the marketing term for wireless Internet access via mobile networks. Access to the network can be made through a portable modem, wireless modem, or a tablet/smartphone or other mobile device. The first wireless Internet access became available in 1991 as part of the second generation (2G) of mobile phone technology. Higher speeds became available in 2001 and 2006 as part of the third (3G) and fourth (4G) generations. In 2011, 90% of the world's population lived in areas with 2G coverage, while 45% lived in areas with 2G and 3G coverage. Mobile broadband uses the spectrum of 225 MHz to 3700 MHz.

In radio, cooperative multiple-input multiple-output is a technology that can effectively exploit the spatial domain of mobile fading channels to bring significant performance improvements to wireless communication systems. It is also called network MIMO, distributed MIMO, virtual MIMO, and virtual antenna arrays.

<span class="mw-page-title-main">MIMO</span> Use of multiple antennas in radio

In radio, multiple-input and multiple-output, or MIMO, is a method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation. MIMO has become an essential element of wireless communication standards including IEEE 802.11n, IEEE 802.11ac, HSPA+ (3G), WiMAX, and Long Term Evolution (LTE). More recently, MIMO has been applied to power-line communication for three-wire installations as part of the ITU G.hn standard and of the HomePlug AV2 specification.

International Mobile Telecommunications-Advanced are the requirements issued by the ITU Radiocommunication Sector (ITU-R) of the International Telecommunication Union (ITU) in 2008 for what is marketed as 4G mobile phone and Internet access service.

In communication networks, cognitive network (CN) is a new type of data network that makes use of cutting edge technology from several research areas to solve some problems current networks are faced with. Cognitive network is different from cognitive radio (CR) as it covers all the layers of the OSI model.

WiGig, alternatively known as 60 GHz Wi-Fi, refers to a set of 60 GHz wireless network protocols. It includes the current IEEE 802.11ad standard and also the IEEE 802.11ay standard.

<span class="mw-page-title-main">Small cell</span> Cellular network infrastructure

Small cells are low-powered cellular radio access nodes that operate in spectrum that have a range of 10 meters to a few kilometers. They are base stations with low power consumption and cheap cost. They can provide high data rates by being deployed densely to achieve high spatial spectrum efficiency.

A Radio Access Technology or (RAT) is the underlying physical connection method for a radio based communication network. Many modern mobile phones support several RATs in one device such as Bluetooth, Wi-Fi, and GSM, UMTS, LTE or 5G NR.

Multiple-input, multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) is the dominant air interface for 4G and 5G broadband wireless communications. It combines multiple-input, multiple-output (MIMO) technology, which multiplies capacity by transmitting different signals over multiple antennas, and orthogonal frequency-division multiplexing (OFDM), which divides a radio channel into a large number of closely spaced subchannels to provide more reliable communications at high speeds. Research conducted during the mid-1990s showed that while MIMO can be used with other popular air interfaces such as time-division multiple access (TDMA) and code-division multiple access (CDMA), the combination of MIMO and OFDM is most practical at higher data rates.

References

  1. ↑ Delphinanto, A.; Hillen, B. A. G.; Passchier, I.; Van Schoonhoven, B. H. A.; Den Hartog, F. T. H. (2009). "Remote Discovery and Management of End-User Devices in Heterogeneous Private Networks". 2009 6th IEEE Consumer Communications and Networking Conference. pp. 1–5. doi:10.1109/CCNC.2009.4784889. ISBN   978-1-4244-2308-8. S2CID   13955396.
  2. ↑ Delphinanto, Archi; Koonen, Ton; Den Hartog, Frank (2011). "End-to-end available bandwidth probing in heterogeneous IP home networks". 2011 IEEE Consumer Communications and Networking Conference (CCNC). pp. 431–435. doi:10.1109/CCNC.2011.5766506. ISBN   978-1-4244-8789-9. S2CID   9558852.
  3. ↑ "HetNet Forecast". Mobile Experts. Archived from the original on 2011-09-18. Retrieved 2011-06-24.
  4. ↑ "HetNet Market Summary & Forecasts: Macro Cells, Small Cells & Wi-Fi Offload". ARCchart. Archived from the original on 2012-11-25. Retrieved 17 November 2012.
  5. ↑ Small Cell Forum (2016). HetNet and SON overview. Small Cell Forum.
  6. ↑ Small Cell Forum (2016). Integrated HetNet architecture framework. Small Cell Forum.
  7. ↑ Small Cell Forum (2016). Role of SON in the HetNet deployment process. Small Cell Forum.
  8. ↑ Melhem El Helou; Samer Lahoud; Marc Ibrahim; Kinda Khawam (April 2013). "A Hybrid Approach for Radio Access Technology Selection in Heterogeneous Wireless Networks". 19th European Wireless Conference -Proceedings. Archived from the original (PDF) on 2003-10-07. Retrieved 2013-10-07.
  9. ↑ Li, Pan; Fang, Yuguang (2010). "The Capacity of Heterogeneous Wireless Networks". 2010 Proceedings IEEE INFOCOM. pp. 1–9. doi:10.1109/INFCOM.2010.5462072. ISBN   978-1-4244-5836-3. S2CID   10140222.
  10. ↑ Barbu, Oana-Elena; Fratu, Octavian (2011). "An enabler of interoperability in heterogeneous wireless networks". 2011 2nd International Conference on Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology (Wireless VITAE). pp. 1–5. doi:10.1109/WIRELESSVITAE.2011.5940885. ISBN   978-1-4577-0786-5. S2CID   15028304.
  11. ↑ Shih Jung Wu (August 2010). "An intelligent handover decision mechanism for heterogeneous wireless networks". Int. Conf. On Networked Computing and Advanced Information Management  -Proceedings: 688–693. Archived from the original (PDF) on 2013-10-07. Retrieved 2013-10-07.
  12. ↑ S. G. T Karetsos, A. Rouskas and F. Foukalas "Energy-efficient traffic bypassing in LTE HetNets with mobile relays." IEEE WiMob, Oct.2015.
  13. ↑ Ernst, Jason B.; Nasser, Nidal; Rodrigues, Joel (2012). "Co-channel interference modelling between RATs in heterogeneous wireless networks". 2012 IEEE International Conference on Communications (ICC). pp. 5321–5325. doi:10.1109/ICC.2012.6364654. ISBN   978-1-4577-2053-6. S2CID   14700286.
  14. ↑ Galanopoulos, Apostolos; Foukalas, Fotis; Tsiftsis, Theodoros A. (2019). "Multi-RAT Aggregation Through Spectrum Reallocation for Future Wireless Networks". Wireless Personal Communications. 111 (3): 1545–1562. doi:10.1007/s11277-019-06939-1. S2CID   255131078.
  15. ↑ Mouhamed Abdulla (2012-09-22). On the Fundamentals of Stochastic Spatial Modeling and Analysis of Wireless Networks and its Impact to Channel Losses (PhD Thesis). Concordia University. Footnote, p. 126.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.