WI-FI Wireless Communication System (3)

WI-FI Wireless Communication System (3)

Wireless Communication

Network security:

The main issue with wireless network security is its simplified access to the network compared to traditional wired networks such as Ethernet, with wired networking one must either gain access to a building (physically connecting into the internal network) or break through an external firewall.

To enable Wi-Fi, one merely needs to be within the wireless range of the Wi-Fi network. Most business networks protect sensitive data and systems by attempting to disallow external access. Enabling wireless connectivity reduces security if the network uses inadequate or no encryption.

An attacker who has gained access to a Wi-Fi network router can initiate a DNS spoofing attack against any other user of the network by forging a response before the queried DNS server has a chance to reply.

Securing methods:

A common measure to deter unauthorized users involves hiding the access point's name by disabling the SSID broadcast. While effective against the casual user, it is ineffective as a security method because the SSID is broadcast in the clear in response to a client SSID query.

Another method is to only allow computers with known MAC addresses to join the network, but determined eavesdroppers may be able to join the network by spoofing an authorized address.

Wired Equivalent Privacy (WEP) encryption was designed to protect against casual snooping but it is no longer considered secure. Tools such as AirSnort or Aircrack-ng can quickly recover WEP encryption keys. Because of WEP's weakness the Wi-Fi Alliance approved Wi-Fi Protected Access (WPA) which uses TKIP.

WPA was specifically designed to work with older equipment usually through a firmware upgrade. Though more secure than WEP, WPA has known vulnerabilities.

The more secure WPA2 using Advanced Encryption Standard was introduced in 2004 and is supported by most new Wi-Fi devices. WPA2 is fully compatible with WPA.

A flaw in a feature added to Wi-Fi in 2007, called Wi-Fi Protected Setup, allows WPA and WPA2 security to be bypassed and effectively broken in many situations. The only remedy as of late 2011 is to turn off Wi-Fi Protected Setup, which is not always possible.

Hotspot (Wi-Fi):

A hotspot is a site that offers Internet access over a wireless local area network through the use of a router connected to a link to an Internet service provider. Hotspots typically use Wi-Fi technology.

Hotspots may be found in coffee shops and various other public establishments in many developed urban areas throughout the world.

Types of Hotspot:

ü Free Wi-Fi hotspots

Free hotspots operate in two ways:

·         Using an open public network is the easiest way to create a free hotSpot. All that is needed is a Wi-Fi router. Private users of wireless routers can turn off their authentication requirements, thus opening their connection, intentionally or not, for sharing by anyone in range.

·         Closed public networks use a HotSpot Management System to control the HotSpot. This software runs on the router itself or an external computer. With this software, operators can authorize only specific users to access the Internet, and they often associate the free access to a menu or to a purchase limit. Operators are also now able to limit each user's available bandwidth - each user is therefore restricted to a certain speed to ensure that everyone gets a good quality service. Often this is done through Service Level Agreements.

ü Commercial hotspots

             A commercial hotspot may feature:

                   ·       A captive portal / Login Screen that users are redirected to   

              for authentication and payment

·       A payment option using credit card, PayPal, iPass, or other

     payment service

·       A walled garden feature that allows free access to certain

     sites

·       Service oriented provisioning to allow for improved revenue

ü Software Hotspots:

Many Wi-Fi adapters built into or easily added to consumer computers include the functionality to operate as hotspots.

Manufacturers can enable this functionality through driver-level support. Modern consumer operating systems, including Windows 7 and later and Apple OS X 10.6 and later added features to support this.

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