IEEE (Institute of Electrical and Electronic Engineers) published the first 802.11 standard in 1997; this was to be known as the first WLAN standard, also known as 802.11 Prime. Throughout the years these standards have been ratified and amended. The first revision was in 1999 with 802.11b, later in 1999 802.11a was amended; in 2003 802.11g was amended and 802.11n was amended in 2009. Of these four standards there are some similarities and differences. The differences between these standards are as follows: * 802.11b – 2.4 GHz ISM, uses HR-DSSS (High Rate Direct Sequence Spread Spectrum), Data rates using DSSS are 1 and 2 Mbps, HR-DSSS uses 5.5 and 11 Mbps. Backward compatible to 802.11 Legacy (Prime) DSSS only. * 802.11a – 5 GHz - UNII, uses Orthogonal Frequency Division Multiplexing (OFDM) allowing for 5 GHz RF frequency’s operating in three different frequency bands called the Unlicensed National Information Infrastructure (UNII). These frequency ranges are: * UNII – 1: 5.150 – 5.250 * UNII – 2: 5.250 – 5.350 * UNII – 3: 5.725 – 5.825
Data rates under this standard were mandatory at 6, 12, and 24 Mbps with optional support for 9, 18, 36, 48, and 54 Mbps. This standard is not backwards compatible. * 802.11g – 2.4 GHz ISM, this standard utilized Extended Rate Physical (ERP) to enhance the physical layer, by using ERP-OFDM & ERP-DSSS/CCK (Complementary Code Keying) Data rates of 6, 9, 12, 18, 24, 36, 48, and 54 Mbps are made available. (ERP-OFDM: 6, 12, 24 Mbps) (ERP-DSSS/CCK: 1, 2, 5.5, 11). This standard is backward compatible with 802.11b HR-DSSS and 802.11 DSSS. 802.11g access points can also be configured 3 modes (B only, G only, or B/G mode). * 802.11n – 2.4 GHz and 5 GHz, this being the newest standard supporting both frequency bands through use of new technology called Multiple Input-Multiple Output (MIMO). This new standard allowed for increases throughput on both frequency’s and greater range. In addition, data rates are being supported up to 600 Mbps. This standard is also backward compatible with 802.11 a/b/g standards.
The standards are beneficial to WLAN in many ways, one way though, is by regulation of frequency bands; however, just like IP addressing do we run the chance of running out of available frequency bands, and how can we expand; or do we change transmission protocols all together to a different carrier medium. As more technologies come out that utilize wireless technology the more bandwidth is going to be needed. Do I think standards limit new technologies, I think it will as more wireless technology comes out looking for faster speeds.

Bibliography
Coleman, D., & Westcott, D. (2012). CWNA certified wireless network administrator official study guide: Exam PWO-104 (3 rd ed.). Indianapolis , IN: Wiley Publishing.