There are about eight types of network which are used world wide these days, both in houses and commercially. These networks are used on the bases of their scale and scope, historical reasons, preferences for networking industries, and their design and implementation issues. LAN and WAN are mostly known and used widely. LAN, local area network was first invented for communication between two computers. LAN operates through cables and network cards. Later WLAN, Wireless local area network was formed through LAN concept, there are no wires involved in communication between computers, and Wireless LAN cards are required to connect to wireless network. LAN is the original network out of which other networks are formed according to requirements. They are as follow.

• LAN - Local Area Network
• WLAN - Wireless Local Area Network
• WAN - Wide Area Network
• MAN - Metropolitan Area Network
• SAN - Storage Area Network, It can also refer with names like System Area Network, Server Area Network, or sometimes Small Area Network
• CAN - Campus Area Network, Controller Area Network, and often Cluster Area Network
• PAN - Personal Area Network
• DAN - Desk Area Network

LAN - Local Area Network

LAN connects networking devices with in short spam of area, i.e. small offices, home, internet cafes etc. LAN uses TCP/IP network protocol for communication between computers. It is often but not always implemented as a single IP subnet. Since LAN is operated in short area so It can be control and administrate by single person or organization.

WAN - Wide Area Network

As “word” Wide implies, WAN, wide area network cover large distance for communication between computers. The Internet it self is the biggest example of Wide area network, WAN, which is covering the entire earth. WAN is distributed collection of geographically LANs. A network connecting device router connects LANs to WANs. WAN used network protocols like ATM, X.25, and Frame Relay for long distance connectivity.

Wireless - Local Area Network  

A LAN, local area network based on wireless network technology mostly referred as Wi-Fi. Unlike LAN, in   WLAN no wires are used, but radio signals are the medium for communication. Wireless network cards are required to be installed in the systems for accessing any wireless network around. Mostly wireless cards connect to wireless routers for communication among computers or accessing WAN, internet.

MAN - Metropolitan Area Network

This kind of network is not mostly used but it has its own importance for some government bodies and organizations on larger scale. MAN, metropolitan area network falls in middle of LAN and WAN, It covers large span of physical area than LAN but smaller than WAN, such as a city.

 CAN - Campus Area Network

Networking spanning with multiple LANs but smaller than a Metropolitan area network, MAN. This kind of network mostly used in relatively large universities or local business offices and buildings.

  SAN - Storage Area Network

SAM technology is used for data storage and it has no use for most of the organization but data oriented organizations. Storage area network connects servers to data storage devices by using Fiber channel technology.     

SAN - System Area Network

SAN, system area networks are also known as cluster area network and it connects high performance computers with high speed connections in cluster configuration.

IEEE 802.11 is standard use world widely for Wireless Local Area network, WLAN, it stands for Institute of Electrical and Electronics Engineers. In simple words it is standard of communication between computers and wireless devices. The standards were set by IEEE LAN/MAN Standard committee in 5GHZ and 2.4 GHz public spectrum bands.

The IEEE 802.11 is consisting of of numerous mechanism and services that interrelate to present station mobility translucent to the higher layers of the network mass. IEEE 802.11 is a combination of wireless LAN. We can use IEEE 802.11 and WiFi often as interchangeably depends on market demand. It is a basic protocol of any high speed wireless network from 1997 to 2008. There are lots of change occurred in it but the basics “high performance" never change. The frequency of it is from 2.4 GHz to 5 GHz and range is from 100 meter to 5000 meter. It specifies a single medium access control as MAC and three physical layers and offering different service such as Authentication of system, Deauthentication of system, data privacy, MSDU delivery, Association with files and system, Disassociation, Distribution of data, Integration of information, and Reassociation. You can configure a station with IEEE 802.11 in different ways as independent configuration, and infra-structure configuration. The IEEE 802.11 starts from the need to connect more than one computer with each other wirelessly especially where the wire cannot go.

IEEE 802.11 required accepting device to activate in a peer-to-peer fashion within the possibly of overlie same as access control level and data transformation services to allow top layers .There are several physical layer represent signaling methods and interfaces. Solitude and safety of user data is being moved over the wireless media via IEEE 802.11.According to OSI model an IEEE 802.11 protocol having direct frequency, hopping sequence, spread spectrum PHY and infrared PHY. IEEE 802.11 specifies a single medium access sub layers called MAC and physical layers with different specifications. The first is physical layers having two radio and infrared. The physical layer contain Frequency Hopping Spread Spectrum Radio PHY offering 1 Mbit/s with two level and 2 Mbit/s with 4 level,  As it is Direct Sequence Spread Spectrum Radio PHY provides DBPSK and DQPSK with 1 and 2 Mbit/s operation, Infrared PHY offer 1 Mbit/s with16-PPM and 2 Mbit/s with –PPM.

These days 802.11a, 802.11b, and 802.11g are mostly in use to create a network home, offices and commercial locations. The architecture of IEEE 802.11 consists of 802.1X for verification, RSN for maintenance track of links, and AES-based CCMP to provide privacy, veracity and basis. IEEE 802.11with the propagation of modems and DSL services makes it reliable. People always desire to set up small networks in their homes to distribute their elevated rate Internet connection. There are many free networks commonly permit anyone within specific range, counting passersby outer, to connect to the Internet. There is also hard work by unpaid helper groups to launch wireless community networks to provide free wireless connectivity to the public. Networking without wire has a talented prospect with 802.11.The dynamic nature of IEEE 802.11 increasing radically in the near future.

Personal area network (PAN) is a computer network designed for communication between computer devices (including telephones and personal digital assistants close to one person). The devices may or may not belong to the person in question. The reach of a PAN is typically a few meters. PANs can be used for communication among the personal devices themselves or for connecting to a higher level network and the Internet.Personal area networks may be wired with computer buses such as USB and FireWire. A wireless personal area network (WPAN) can also be made possible with network technologies such as IrDA and Bluetooth.

SECURITY THREAT AND REQUIREMENTS OF WIRELESS PAN

Bluetooth offers several benefits and advantages. However, organizations must not only address the security threats associated with Bluetooth before they implement the technologies; they must also measure the vulnerabilities of the devices they allow to participate in the Bluetooth networks. Specifically, agencies need to address security concerns for confidentiality, data integrity, and network availability. Moreover, since Bluetooth devices are more likely to be managed by users that are less security conscious than administrators, they are more likely to contribute to uncontrolled security drifts. This subsection will briefly cover some of the risks to security, i.e., attacks on confidentiality, integrity, and network availability.

Loss Of Confidentiality

Threats to confidentiality involve, first of all, compromised Bluetooth devices. When a Bluetooth device that is part of a piconet becomes compromised (e.g., is in the possession of an unauthorized user), it may still receive information that the malicious user should not access. Moreover, the compromised device may still have network or information privileges, resulting in a compromise of the wider network as well. In the latter case, the compromised device may not only receive normal proprietary traffic but may also request that information as part of a targeted network attack. A trait of Bluetooth that makes this compromise unique is that the Bluetooth network requires device and not the user authentication to access resources. Once the device is authenticated, it is automatically connected to resources without the need for subsequent authentication. (Geoff Huston, the wireless internet)

Loss Of Integrity

Iinfringements of integrity result from the corruption of an organization’s or user’s data. The direct effect is similar to that of a confidentiality, or disclosure, threat: a compromised network. However, integrity threats extend beyond this, involving the alteration, addition, or deletion of information, which is then passed through the network without the user’s or network administrator’s knowledge. Information that is subject to corruption includes files on the network and data on user devices. For example, a malicious user might use an untrusted device, such as a PDA, to access the address book of another PDA or laptop. However, instead of just monitoring the information, as would be the case with a disclosure threat, the malicious user alters the contact information without the owner’s knowledge or may even delete the information completely. If undetected, such attacks could result in the agency or user losing confidence in its data and system. Users should verify that their Bluetooth product does not allow automatic data synchronization to prevent the alteration of any information without the acknowledgement user of that device.

Loss Of Avaiability

Denial of service attacks cause in the loss of network availability for authorized users and devices. Denial of service attacks block authorized user access to system resources and network applications. Besides the typical DoS attacks directed against LANs and Internet services, Bluetooth devices are also susceptible to signal jamming. Bluetooth devices share bandwidth with microwave ovens, cordless phones, and other wireless networks and thus are exposed to interference. Malicious users can interfere with the flow of information by using devices that transmit in the 2.4 GHz ISM band. Disrupting the routing protocol prevents ad hoc network devices from negotiating the network’s dynamic topologies. Remote users may encounter jamming more frequently than on-site users. Remote users must contend with the same interference that users experience in the office. Further, since the remote environment is uncontrolled, remote devices are more likely to be in close immediacy to devices that are intentionally or unintentionally jamming their signals.       Another threat associated with ad hoc devices is a battery exhaustion attack. This attack attempts to disable a device by draining its battery. A malicious user continually sends requests to the device asking for data transfers (assuming the user is part of the network topology) or asking the device to create a network. Although this type of attack does not compromise network security, it ultimately prevents the user from gaining access to the network, because the device cannot function. (Juha T. Vainio, May 25, 2000)

SOLUTIONS & SECURITY MEASURES FOR WPAN

Wireless Personal Area Network and other Bluetooth technologies are relatively new standard and have yet to become common in the marketplace. However, solutions and improvements are available to help secure WPAN networks. These measures include management solutions, operational solutions, and technical solutions

Management Solutions.

The first line of protection is to provide a sufficient level of knowledge and understanding for those who will deal with WPAN & Bluetooth enabled devices & networks. Organizations using wireless personal area network technology need to establish and document security policies that address the use of Bluetooth enabled devices and the user’s responsibilities. The policy document should include a list of approved uses for WPAN’s, the type of information that may be transferred in the network, and any disciplinary actions that may result from misuse. The security policy should also specify a proper password usage scheme.

Operational Solutions

Since Bluetooth devices do not register when they join a network, they are invisible to network administrators. Consequently, it is difficult for administrators to apply traditional physical security measures. However, there are some security approaches that can be applied, including establishing spatial distance and securing the gateway Bluetooth devices that connect remote Bluetooth networks or devices. Establishing spatial distance requires setting the power requirements low enough to prevent a device operating on the organizations premises from having sufficient power to be detected outside physical boundaries. This spatial distance in effect creates a more secure boundary. Currently, Bluetooth devices have a useful range of approximately 30 feet. Organizations that require both high levels of security and low levels of security should maintain a secure perimeter so that on site network users can maintain secure connections in their office premises. Agencies with requirements for high levels of security should also restrict unauthorized personnel from using PDAs, laptops, and other electronic devices within the secure perimeter. (Tom karygiannis, Les Owens, Nov 2002)

Technical Solutions

As with WLANs and Bluetooth technical solutions & improvements fall into one of two categories: software security solutions and hardware security solutions. Bluetooth software solutions focus on Personal Identification Number (PIN) and private authentications, while hardware solutions involve the use of the Bluetooth device address and link keys that reside at the link level. Again, it should be noted that hardware solutions, which generally have software components, are into simply as hardware solutions.