A Wireless LAN (WLAN) is a data transmission system that enables location-independent network access using radio waves instead of cables. Advantages include increased productivity, easy setup, flexibility, cost reduction, and scalability, making it suitable for various environments like enterprises, educational institutions, and temporary networks. Security measures for WLAN include authentication, encryption, and intrusion detection systems to safeguard against unauthorized access and security risks.

1. Wireless Ethernet
By Javier Torres

2. What is a Wireless LAN (WLAN) ?
A data transmission system designed to provide location-independent network
access between computing devices by using radio waves rather than cable
infrastructure, it can be also known as “WI-FI” or “802.11” network.

3. Benefits of using WLAN instead of wired
network connection
• Increased productivity – WLAN provides “untethered” network and internet
access.
• Fast & Simple network set up – There are no cables to install at a user's desk or
work area.
• Installation flexibility – WLANs can be installed in places where wires can’t, and
they facilitate temporary set-up and relocation.
• Reduced Cost-of-Ownership – Wireless LANS reduce installation cost because
there is no cabling.
• Scalability – Network expansion and reconfiguration may be less complicated
than expanding a wired network.

4. Where is WLAN mainly applied?
• Dynamic environments
• Old buildings, cost-effective network
infrastructure solution
• Temporary networks on exhibitions
and seminars
• Backup for mission-critical
applications running on wired
networks
• Enterprise networks
• Small / Home-office networks
• Education – Schools and Universities

5. Infrastructure Wireless LAN
▪ Link between LAN hub and mobile data
terminal
- Laptop or notepad computer
- Enable employee returning from trip to
transfer data from portable computer to
server
▪ Also useful in extended environment such
as campus or cluster of buildings
- Users move around with portable computers
- May wish access to servers on wired LAN

6. Architecture of an ad-hoc network
❖ Direct communication within a limited
range
▪ Station (STA): Terminal with access
mechanisms to the wireless medium.
▪ Independent Basic Service Set (IBSS):
Group of stations using the same radio
frequency.

7. Range & Throughput
▪ 802.11b data rate
- 5 Mbps
- 11 Mbps
▪ Indoor range (typical) – 45 to 90 meters
▪ Outdoor range – *Kilometers ( depends on external antenna )
▪ Throughput decreases with distance

8. Wireless Lan security
To secure a WLAN, the following components
are required:
▪ Authentication: To ensure that legitimate
clients and users access the network via
trusted access points
▪ Encryption: To provide privacy and
confidentiality
▪ Intrusion Detection Systems (IDS) and
Intrusion Protection Systems (IPS): To
protect from security risks and availability