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Upcoming Standards in Wireless Local Area Networks Preprint: http://arxiv.org/abs/1307.7633 Original Publication: UPCOMING STANDARDS IN WIRELESS LOCAL AREA NETWORKS Sourangsu Banerji Department of Electronics & Communication Engineering, RCC-Institute of Information Technology, India Email: [email protected] ABSTRACT: Network technologies are However out of every one of these standards, traditionally centered on wireline solutions. WLAN and recent developments in WLAN Wireless broadband technologies nowadays technology will be our main subject of study in this particular paper. The IEEE 802.11 is the most provide unlimited broadband usage to users widely deployed WLAN technology as of today. that have been previously offered simply to Another renowned counterpart is the HiperLAN wireline users. In this paper, we discuss some of standard by ETSI. These two technologies are the upcoming standards of one of the emerging united underneath the Wireless Fidelity (Wi-fi) wireless broadband technology i.e. IEEE alliance. In literature though, IEEE802.11 and Wi- 802.11. The newest and the emerging standards fi is used interchangeably and we will also continue with the same convention in this fix technology issues or add functionality that particular paper. A regular WLAN network is will be expected to overcome many of the associated with an Access Point (AP) in the current standing problems with IEEE 802.11. middle/centre and numerous stations (STAs) are connected to this central Access Point (AP).Now, Keywords: Wireless Communications, IEEE there are just two modes in which communication 802.11, WLAN, Wi-fi. normally takes place. 1. Introduction Within the centralized mode of communication, The wireless broadband technologies were communication to/from a STA is actually carried developed with the objective of providing services across by the APs. There's also a decentralized just like those supplied by, on the wireline mode in which communication between two STAs networks. Cellular networks now provide support can happen directly without the requirement for top bandwidth data transfer for numerous associated with an AP in an ad hoc fashion. mobile users simultaneously. In view of this, WLAN networks provide coverage up to a place of additionally, they provide mobility support for 50-100 meters. Initially, Wi-fi provided an voice communication. Wireless data networks may aggregate throughput of 11Mbps, but recent be separated into several types depending with developments have increased the throughput to their area of coverage. They are: around 54 Mbps. Because of its high market penetration, several amendments on the basic IEEE WLAN: Wireless Local Area network, in area that 802 standard are developed or are now under has a cell radius up to hundred meters, mainly in development. office and home environments. WMAN: Wireless Metropolitan Area Network; In this paper, we address the technical context generally cover wider areas as huge as entire cities. of its latest amendments. In section 2, we briefly WWAN: Wireless Wide Area Network that has a discuss the history behind the development of the cell radius about 50 km, cover areas bigger a city. standard. Section 3 deals with the features of the IEEE 802 family which have already been implemented. In section 4, the upcoming standards Preprint: http://arxiv.org/abs/1307.7633 Original Publication: are discussed and some open issues with the IEEE 3. IEEE 802.11 family 802.11 standard is given in section 5. Lastly we The absolute and the most widely deployed conclude our paper in section 6. 802.11 standard have plenty of extension and additional amendments are now under 2. Development of IEEE 802.11 development. First introduced in 1999, the IEEE The Physical layer (PHY) and medium access 802.11 standards were primarily developed bearing control (MAC) layer were mainly targeted by the in minds our home and work environment for IEEE 802 project. When the thinking behind wireless local area connectivity. The initial wireless local area network (WLAN) was first standards gave a maximum data rate of 2Mbps per conceived, it was just thought of another PHY of AP which risen up to 11 Mbps per AP with the one of many available standards. The earliest deployment of IEEE 802.11b [2].Newer extensions candidate which was considered for it was IEEE's like IEEE 802.11g and IEEE 802.11a provided most prominent standard 802.3. maximum data rate of 54Mbps per AP using various methods to improve up the utmost data However later findings indicated that the radio rates [3-5]. WLAN devices based on IEEE 802.11g medium behaved quite diverse from the common currently offer data rate 100-125Mbps [4]. well behaved wire. Concerning was attenuation even over short distances, as well as collisions Similarly, a comparatively newer IEEE 802.11n which could not be detected. Hence, 802.3's carrier provides maximum data rate around 540Mbps sense multiple access with collision detection [25].Furthermore, various other standards were (CSMA/CD) could not be applied. deployed which solved many QoS and security issues related with the newer standards. Additional Another candidate standard considered was mechanisms were introduced to treat QoS support 802.4. At that time, its coordinated medium access and security problems in IEEE 802.11e [12] and i.e. the token bus concept was considered IEEE 802.11i.The IEEE 802.11n standard which preferable over 802.3's contention-based scheme. we earlier discussed also introduced MAC Hence, WLAN began as 802.4L. Later in 1990 it enhancements to overcome MAC layer limitations became obvious that token handling in radio in today's standards [28]. The IEEE 802.11s networks was rather difficult. The standardization standard added mesh topology support to the IEEE body realized they will need a wireless 802.11 [34]. The IEEE 802.11u improved communication standard that could have a very internetworking with external non-802.11 unique MAC. Finally, on March 21, 1991, the networks. The IEEE 802.11w was an additional project 802.11 was approved (fig. 1). onto 802.11i covering management frame security. The IEEE 802.11ad standard adds a "fast session transfer" feature, enabling the wireless devices to seamlessly make transition involving the legacy 2.4 GHz and 5 GHz bands and the 60 GHz frequency band [41]. The IEEE 802.11ac standard, under development is expected to supply a multi- station WLAN throughput of at the very least 1 Gbps and just one link throughput of at the very least 500 Mbps [45]. 4. Upcoming Standards 4.1. IEEE 802.11ad The IEEE 802.11ad also referred to as WiGig is Figure 1 WLAN Network Architecture really a relatively new standard published in December 2012. It specification adds a "fast Preprint: http://arxiv.org/abs/1307.7633 Original Publication: session transfer" feature, enabling the wireless information on which frequency, at what time and devices to seamlessly make transition in the under what conditions networks may operate. legacy 2.4 GHz and 5 GHz bands and the 60 GHz frequency band [41]. To provide for optimal 4.5. IEEE 802.11ah performance and range criteria, the IEEE 802.11ad The IEEE 802.11ah is directed at developing an provides the capability to move in between the international WLAN network which will allow bands ensuring that computing devices are usually user to gain access to sub carrier frequencies below "best connected," 1GHz in the ISM band. It will even enable devices on the basis of the IEEE 802.11 standards to access Through the vast improvements in spectral short burst data transmissions like meter data. reuse at 60 GHz and an efficient beam forming Additionally it can provide improve coverage technology, IEEE 802.11ad enables great range that will allow new applications such as, for improvements in capacity [42]. Many users in a example wide area based sensor networks, sensor thick deployment can all maintain top-speed backhaul systems and potential Wi-Fi off-loading performance, without interfering with one another functions to emerge [48]. This standard is under or having to generally share bandwidth just like the development and is predicted to be finalized by legacy frequency bands [43-44]. The likely 2016. enhancements to 802.11 beyond a brand new 60 GHz PHY include MAC modifications for 4.6. IEEE 802.11ai directional antennas, personal basic service set, The IEEE 802.11ai is a forthcoming standard beamforming, fast session transfer between PHYs predicted to be finalized by 2015. It'll add a fast and spatial reuse. initial link setup (FILS) that might enable an STA to reach a protected link setup that will be 4.2. IEEE 802.11ae significantly less than 100 ms [49]. An effective The IEEE 802.11ae introduces a mechanism for link setup process will then permit the STA to send prioritization of management frames. A protocol to IP traffic with a valid IP address through the AP. communicate management frame prioritization policy is specified in this standard. 4.7. IEEE 802.11mc The IEEE 802.11mc resembles the IEEE 4.3. IEEE 802.11ac 802.11m and is also scheduled to appoint an Among the important standards currently under operating group with the job of maintenance of the development is IEEE 802.11ac. This standard is standard around 2015. anticipated to be published by the end of 2014. It's expected to supply a multi-station WLAN throughput of at the least 1 Gbps and an individual 4.8. IEEE 802.11aj link throughput of at the least 500 Mbps [45]. That The IEEE 802.11aj provide modifications to is accomplished by extending the air interface the IEEE 802.11ad Physical (PHY) layer and the concepts which are embraced by 802.11n like Medium Access Control (MAC) layer for wider RF bandwidth (up to 160 MHz), more operation in the Chinese Milli-Meter Wave MIMO spatial streams (up to 8), multi-user (CMMW) frequency bands like the 59-64 GHz MIMO, and high-density modulation [45-47].
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