Wi Max
Wi Max
Wi Max
Technology
Contents
• Wireless Technologies
• Types of Wireless Technologies
• What is Wi Max ?
• Wi Max Building Blocks
• MAC Layer in Wi Max Tower
• Types of Wi Max Services
• Security Functions
• Specifications of Wi Max
• Benefits of Wi Max
• Wi Max vs Wi-Fi
Types of Wireless Communication
Technologies
• Bluetooth
• Wi-Fi
• Zig – Bee
• Wi Max
What is Wi Max ?
• WIMAX stands for Worldwide Interoperability for Microwave
Access.
2) A WiMAX receiver.
Wi Max Tower
Wi MAX Base Station
• A WiMAX base station consists of indoor
electronics and a WiMAX tower similar in
concept to a cell-phone tower.
• A WiMAX base station can provide coverage to
a very large area up to a radius of 6 miles.
• Any wireless device within the coverage area
would be able to access the Internet.
• The WiMAX base stations would use the MAC
layer defined in the standard, a common interface
that makes the networks interoperable and would
allocate uplink and downlink bandwidth to
subscribers according to their needs, on an
essentially real-time basis.
• Each base station provides wireless coverage over
an area called a cell. Theoretically, the maximum
radius of a cell is 50 km or 30 miles however,
practical considerations limit it to about 10 km or
6 miles.
WiMAX Receiver
• A WiMAX receiver may have a separate
antenna or could be a stand-alone box or a
PCMCIA card sitting in your laptop or
computer or any other device. This is also
referred as customer premise equipment
(CPE).
• WiMAX base station is similar to accessing a
wireless access point in a WiFi network, but
the coverage is greater.
MAC layer
• MAC was designed for point-to-multipoint
broadband wireless access applications.
• The MAC layer is responsible for moving data
packets to and from one Network Interface Card
(NIC) to another across a shared channel.
• The primary task of the Wi MAX MAC layer is to
provide an interface between the higher
transport layers and the physical layer.
• The MAC layer takes packets from the upper
layer, these packets are called MAC service
data units (MSDUs) and organizes them into
MAC protocol data units (MPDUs) for
transmission over the air.
• For received transmissions, the MAC layer
does the reverse.
WiMAX - Security Functions
• Security is handled by a privacy sublayer
within the WiMAX MAC. The key aspects of
WiMAX security are as follow −
1. Support for Privacy
2. Device/user Authentication
3. Flexible Key-management Protocol
Support for Privacy
• User data is encrypted using cryptographic
schemes of proven robustness to provide
privacy. Both AES (Advanced Encryption
Standard) and 3DES (Triple Data Encryption
Standard) are supported.
• The 128-bit or 256-bit key used for deriving
the cipher is generated during the
authentication phase and is periodically
refreshed for additional protection.
Device/user Authentication
• WiMAX provides a flexible means for
authenticating subscriber stations and users to
prevent unauthorized use.
• The authentication framework is based on the
Internet Engineering Task Force (IETF) EAP, which
supports a variety of credentials, such as
username/password, digital certificates, and
smart cards.
Flexible Key-management Protocol
• The Privacy and Key Management Protocol
Version 2 (PKMv2) is used for securely
transferring keying material from the base
station to the mobile station, periodically re-
authorizing and refreshing the keys.
Features of Wi Max
• Scalability - WiMAX has a scalable physical-layer architecture that
allows for the data rate to scale easily with available channel bandwidth.