May 2020 | BlogMech

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What is WiMAX | Worldwide Interoperability for Microwave Access | Next Generation 4G Wireless Technology

By magnaparthi on 31/05/2020

WiMAX, which stands for “Worldwide Interoperability for Microwave Access,” is a subset of standard, interoperable implementations within the IEEE 802.16 family of standards developed by the Institute of Electrical and Electronics Engineers (IEEE) 802.16 Working Group on Broadband Wireless Access Standards.

WiMAX is the next-generation of wireless technology designed to enable pervasive, high-speed mobile Internet access to the widest array of devices including notebook PCs, handsets, smart phones, and consumer electronics such as gaming devices, cameras, camcorders, music players, and more. As the fourth generation (4G) of wireless technology, WiMAX delivers low-cost, open networks and is the first all IP mobile Internet solution enabling efficient and scalable networks for data, video, and voice. As a major driver in the support and development of WiMAX, Intel has designed embedded WiMAX solutions for a variety of mobile devices supporting the future of high-speed broadband on-the-go.

How does WiMAX Works?

Think of WiMAX as taking the best part of cellular network access– the part that allows you to easily connect anywhere within your service provider’s wide coverage area and taking the best part of your Wi-Fi experience—the fast speeds and a familiar broadband Internet Experience . And combining them into a new wireless standard.

WiMAX is a Wide Area Network (WAN) technology. Service providers will deploy a network of towers that will enable access over many miles. Internet access is instantly available anywhere within coverage areas. And like Wi-Fi, WiMAX is a standards-based technology that will unleash the benefits of open markets and global economies of scale to deliver the devices and services that consumers want.

Imagine Broadband on the Go:

Broadband that travels with you across town or across the nation makes all things Internet available on your terms. WiMAX enables the freedom and convenience that comes from having your Internet standing by where and when you need it—staying connected on the go to the people, communities, and resources that make up our lives. Broadband on the go is your front row seat to all the rich multimedia Internet applications you already use, and exciting future possibilities enabled by Mobile WiMAX. •

Playing in Real-Time.:

Play multiplayer 3-D games, view YouTube* videos, listen to radio broadcasts—it’s all there waiting to entertain you on the go.

Working Smarter:

WiMAX pulls productivity out of thin air. Capture lost time by doing things in areas previously unavailable.

Working on the go changes the rules of competition by allowing you to be more productive.

Staying in Touch:

Broadband on the go is about keeping in touch with family, friends, and your communities using all the typical tools like e-mail and IM, but WiMAX adds face-to-face video conferencing and voice to your connections.

Locating People and Places.

WiMAX enables a spontaneous lifestyle. Location-based services creates a new paradigm in accessing real-time information where and when you need it. Mobilizing Your Internet 6.

Receiving TV and Radio on the Go.

There are just more streams of data available with WiMAX, so why not pipe broadcast television and radio into a Mobile WiMAX device? Radio stations already co-broadcast over the Internet. Mobile Internet-based TV transmissions also set the stage for content-on-demand services like movies and sporting events.

Get Ready for WiMAX:

Major wireless service providers are already planning to roll out WiMAX, and Intel is enabling mass market adoption of WiMAX in notebooks and other mobile Internet devices similar to the way it enabled Wi-Fi in notebooks. WiMAX is a global, standards-based technology that is being adopted and deployed in many countries around the world.

Posted in: 4G wireless technology, embedded wimax, next generation wireless technology, wan, wi-Fi, wide are network technology, wimax, Worldwide Interoperability for Microwave Access

Interview Questions Latest Interview Questions & Answers

What is WEP

By magnaparthi on 31/05/2020

WEP, which could stand for either Wired Equivalent Privacy or Wireless Encryption Protocol, is a security scheme employed by the Institute of Electrical and Electronics Engineers (IEEE) for IEEE 802.11 wireless networks since the standard’s ratification in September 1999. WEP was part of the IEEE 802.11 standard and its amendments up until IEEE 802.11i, when it was replaced by Wi-Fi Protected Access (WPA) and WPA2.

Wireless networks require more security than wired networks since wireless networks broadcast messages using radio, so they are more prone to eavesdropping. For confidentiality, WEP makes use of the stream cipher RC4, also known as ARCFOUR, and understood to stand for “Rivest Cipher 4” or “Ron’s Code” after the cipher creator, Ron Rivest.

For integrity, it makes use of the Cyclic Redundancy Check 32 (CRC-32) checksum. A 40-bit key, concatenated with a 24-bit initialization vector (IV) to form the RC4 traffic key, is used by standard 64-bit WEP. Key size was limited by U.S. Government export restrictions on cryptographic technology during the period of drafting for the original WEP standard. These limitations on key size were eventually lifted, but by then all of the major computer manufacturers had used a 104-bit key size in their implementations of an extended 128-bit protocol.

Users often enter a 128-bit WEP key as a string of 26 Hexadecimal (Hex) characters, from 0 to 9 and A to F, with each character representing 4 bits of the key. 26 characters with 4 bits each results in a total of 104 bits, which, when added to the 24-bit IV, forms the 128-bit WEP key.

Some vendors provide a 256-bit WEP system, which uses 24 bits for the IV and 232 bits for protection, usually entered as 58 Hexadecimal characters with each character representing 4 bits of the key.

In addition to the government restrictions on key size, another major security limitation in WEP is that interception of more packets is required in cracking a longer key, but there are active attacks that stimulate the necessary traffic. IV collisions and altered packets are also possible weaknesses in WEP, and a longer key only worsens these problems.

WEP features two methods of authentication:

Open System authentication, where it is unnecessary for a WLAN client to provide its credentials to an Access Point during authentication; and

Shared Key authentication, which uses a four-way challenge-response handshake.

Cryptanalysts were able to identify several serious weaknesses in the WEP in the early 2000’s, finding that a WEP connection could easily be cracked with available software in a matter of minutes. This problem was solved by the introduction of a new security scheme, WPA, in 2003, and the IEEE 802.11i standard, which used WPA2, in 2004.

Prior to the inception of WPA and WPA2, however, a number of replacements for WEP had been developed with the goal of restoring security to the wireless network itself. These replacements include: WEP2, which is a stopgap enhancement to WAP that features an enlarged IV value and enforced 128-bit encryption; WEPplus or WEP+, developed by Agere Systems that avoids “weak IVs” to enhance WEP security; and Dynamic WEP, which dynamically changes WEP keys.