Priyam Vaidya's Blog

Authentication means making sure that something is what it claims to be. E.g., in online banking, you want to make sure that the remote computer is actually your bank, and not someone pretending to be your bank. The purpose of 802.1x is to accept or reject users who want full access to a network using 802.1x. It is a security protocol that works with 802.11 wireless networks such as 802.11g and 802.11b, as well as with wired devices. In a wireless network, 802.1x is used by an access point to implement WPA. In order to connect to the access point, a wireless client must first be authenticated using WPA. In a wired network, switches use 802.1x in a wired network to implement port-based authentication. Before a switch forwards packets through a port, the attached devices must be authenticated. After the end user logs off, the virtual port being using is changed back to the unauthorized state. A benefit of 802.1x is the switches and the access points themselves do not need to know...

802.11ac and how it compares to 802.11n: 802.11ac leverages many of the same key technologies as 802.11n, including channel bonding and MIMO (multiple input, multiple output), it just does it a bit smarter. Let’s take channel bonding, for example. Channel bonding is a very efficient method that essentially doubles the data rate, regardless of other technologies in use. But it does have some practical limitations, and many companies are not taking advantage of what should be an easy data rate enhancement. Why? Although 802.11n is designed for both the 2.4 and 5GHz bands, many users are deploying 11n in only the 2.4GHz band, mainly for backward compatibility with existing b/g clients. Given the limited bandwidth and tight channel allocation in the 2.4GHz band, there’s not much flexibility to make channel bonding work, and when configured incorrectly, it can cause serious interoperability issues with existing b/g deployments, whether the user’s or their neighbor’s. In order to combat...

A family of IEEE standards that extend the common wired Ethernet local network standard into the wireless domain. The 802.11 standards are widely known as "Wi-Fi" because the Wi-Fi Alliance provides certification for 802.11 products. There have been four major 802.11 standards designated with letter suffixes (a, b, g and n); the latest and fastest being 802.11n (the slowest is 802.11b, and the two medium speed are 802.11a and 802.11g). For more about Wi-Fi networks, Following are the 802.11 specifications, from slowest to fastest. Very Slow Speeds (1997) The first 802.11 specifications included two spread spectrum methods in the unlicensed 2.4 GHz band: 1 Mbps frequency hopping (FHSS) and 1 and 2 Mbps direct sequence (DSSS). It also included an infrared method. Both FHSS and infrared were dropped by the Wi-Fi Alliance, but 1 Mbps DSSS method is still used by access points to advertise themselves 11b (1999) - Slow Speed Using DSSS and the 2.4 GHz band, 802.11b boosted ...

Is 5GHz Wireless better than 2.4GHz ? Wireless computer network equipment typically uses radio signals in either a 2.4 GHz range or a 5 GHz range. The GHz range of a wireless radio is only partially related to the speed of a wireless network. For example, 802.11a wireless operates at 5GHz and 802.11g at 2.4GHz, but both support the same maximum data rate of 54 Mbps. However, newer 802.11n routers have the capability of simultaneous dual-band operation on both 5GHz and 2.4GHz ranges, allowing clients to connect on different bands for more flexibility and less interference. 802.11ac expands on that, running entirely in the 5GHz band. Advantages of 5GHz: The 5GHz band is less likely to be congested. The 2.4GHz frequency range is much more prone to interference, as it is commonly used by other wireless networks in the area, as well as cordless phones, garage door openers and other home appliances and consumer products. The 5GHz band can also offer much higher throughput (usin...