Unit 10 Wireless Networking

IEEE 802.15.4 ZigBee

- 2.4 GHz mesh LAN protocol - developed as an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios - transmit data over long distances by passing it through a mesh network of intermediate devices to reach more distant ones - defined rate of 250 kbps and are secured by 128-bit symmetric encryption keys - typically used in low-data-rate applications that require high scalability, long battery life, and secure networking - simple and less expensive than Bluetooth or Wi-Fi - commonly used for home, building and industrial automation applications, such as controlled lighting and thermostats, home energy monitors, smart metering, medical device data collection, traffic management systems and other low-power, low bandwidth needs

CSMA/CA

- Carrier Sense Multiple Access/Collision Avoidance - network contention protocol that listens to a network in order to avoid collisions - unlike CSMA/CD that deals with network transmissions once collisions have been detected - internationally standardized in IEEE 802.11

Hybrid Network

- Hybrid AP relies on wireless as well as wired signals - Hybrid router transmits Wi-Fi signal but also contains ports connected to any digital subscriber line (DSL) modem or cable through Ethernet cables - most common is every wired device plugged into hybrid router's Ethernet ports - popular due to accessibility and cost-saving factors - security is biggest concern

Wireless Local Area Network (WLAN)

- Sometimes known as LAWN (Local Area Wireless Network) - ireless computer network that links two or more devices using a wireless distribution method within a limited area such as a home, school, computer laboratory, or office building. - wirelessly connects coverage cells to provide services to an expanded geographical location. - can be constructed through any kind of wireless network protocol, but the most common way of connection is through Wi-Fi for distances up to 100 meters - gives users the ability to move around within a local coverage area and still be connected to the network, and can provide a connection to the wider Internet. - Most modern WLANs are based on IEEE 802.11 standards, marketed under the Wi-Fi brand name. - support can range from two or more devices. - need to rely on repeaters or signal boosters to cover a vast geographical location. - caters to devices such as laptops, mobile phones, tablets computers, gaming console, internet audio system, and internet-powered home devices and appliances

WPAN

- WPAN uses a wireless communication medium instead of a wired connection. - Typically, the devices in WPAN include peripheral and hand-held devices such as personal digital assistants (PDAs), smart phones and tablet personal computers (PCs). - range depends on the wireless router's capabilities, access point or the device itself, but it is usually restricted to a house or small office. - can be created using Wi-Fi, Bluetooth, or infrared or any similar wireless technologies.

WLAN

- Wi-Fi is a technology based on the IEEE 802.11 suite of standards that uses radio frequencies (RF) to extend wired Ethernet-based LANs to Wi-Fi-enabled devices. - a network that allows devices to connect and communicate wirelessly. - Unlike a traditional wired LAN, in which devices communicate over Ethernet cables, devices on a WLAN communicate via Wi-Fi. - While a WLAN may look different than a traditional LAN, it functions the same way.

IEEE 802.15.1 Bluetooth

- a standard for the short-range wireless interconnection of mobile phones, computers, and other electronic devices. - sends and receives radio waves in a band of 79 different frequencies (channels) centered on 2.45 GHz, set apart from radio, television and cellphones, and reserved for use by industrial, scientific and medical - global 2.4 GHz PAN for short-range wireless communication - very low power consumption; more secure than Wi-Fi - Device-to-device file transfers, mobile credentials, wireless speakers and wireless headsets are often enabled with Bluetooth

Wireless Ad Hoc Network

- ad hoc means something improvised or a makeshift device. - can sustain itself without any existing infrastructure, it is decentralized and regarded as a peer-to-peer network. - does not rely on a wireless router or central Access Point to transmit data from one point to another. - each of its nodes sends and receives data that is circulated evenly through the existing structure - nodes are free to communicate with each other without any barrier. - node in this setting can be defined as a single device that receives or transfers data to nearby devices. - can be created in any environment and under any circumstances, this quality makes them ideal for larger organizations, Small and mid-size enterprises, or ordinary personal usage

wireless network

- capable of joining two or more devices through radio waves - access point: device that creates wireless local area network usually in office or large building > the most important element in wireless network > connects to wired router or switch via an Ethernet cable, and transmits Wi-Fi signal to designated area - network node: device used in LANs and WANs that performs specific function > each node needs MAC address for each network interface card (NIC) - service set: collection of wireless networking devices with same parameters - service set identifier (SSID): Identifier (name) that tells you which service set (or network) to join

multifunction access point

- combination of multiple devices; an access point, a regular Ethernet switch, a router and sometimes a modem - an additional device or devices are merged with the access point to provide the additional functionalities along with existing functionality of the access point. ex: A wireless router which internet service providers use to provide to the internet connection

Extended Service Set Identifier (ESSID)

- consists of all BSSs in network - Access points in an ESS are connected by a centralized distribution system. - This is the type of system we have at Dolan Hall, every class room has an AP that broadcasts our "LWS" ESSID or just simply SSID. - ad-hoc network for example, the network generates a 48-bit string of numbers that looks and functions just like a MAC address, and that BSSID goes in every packet.

lightweight access point

- controlled access point - works as client of wireless lan controller (WLC) - doesn't make any forwarding decision > Upon receiving a frame from the connected device, instead of forwarding it to the destination device, it forwards that frame to the WLC. > The WLC, based on the security configuration, makes decision whether the received frame should be forwarded or discarded. > If the frame needs to be forwarded, then it sends that frame to that LWAP, to which the destination device is connected. Then that LWAP sends this frame to the destination device.

Wireless Wide Area Network (WWAN)

- covers wireless networks over wide area - achieved by wirelessly connecting coverage cells to provide services to expanded geographical location - typically used to cater smartphones' market through cellular service providers - coverage of large service areas such as cities, regions or even countries - Commonly deployed WWAN technologies include GSM/GPRS/EDGE, CDMA2000, UMTS/HSDPA and CDMA EV-DO. - different from a normal Wi-Fi connection because in a Wi-Fi setting, individuals can enjoy wireless services through any hotspot - specific handheld devices need to be specifically provisioned (or subscribed) to gain access to any service provider's network.

IEEE 802.15.16 WiMax

- developed separately from Wi-Fi - designed for long-range networking (spanning miles or kilometers) as opposed to local area wireless networking

IEEE 802.15.7 Li-Fi

- form of visual light communication that uses light waves from Light Emitting Diodes (LEDs) for high-speed wireless communication. - exchange data quickly and securely at a much lower power level compared to Wi-Fi. - fewer interference issues than RF technology, making it ideal for dense environments where Wi-Fi may fall short. - can't penetrate solid materials, which makes it more secure - a Li-Fi network in a building would need multiple transmitter LEDs, so a mobile user could experience seamless wireless coverage as they move between the illumination areas of each LED - potential applications for the Internet of Things in many industries, including aerospace, education, consumer electronics, healthcare, retail, security and transportation, among others.

Autonomous access points

- have all the software required to manage the WLAN processes with no need for additional controllers or switches. - original type of access point and ranged from one to ten access points across the network.

Basic Service Set Identifier (BSSID)

- identify access points and their clients. Packets bound for devices within the WLAN need to go to the correct destination. - included in all wireless packets - Each access point has its own basic service set (BSS) and the MAC address is used as the ID of a BSS (BSSID). - ad-hoc network, a network that forwards traffic from node to node, has no access point; network generates 48-bit string of numbers that looks and functions like MAC address and that BSSID goes in every packet

wireless advantages

- increased mobility and collaboration - roam without losing connection - connect hard-to-reach areas

Wireless Metropolitan Area Network (WMAN)

- intended to cover an area that ranges around 31 miles or 50 kilometers is a WMAN - also called a Base Area Network (BAN) or a Campus Area Network (CAN) - allows multiple locations or buildings to stay connected within any metropolitan area - used to connect different campuses of a single university, various blocks of a hospital, and multiple office buildings - relies on strong radio waves or infrared light to transmit data. - often used as backup for wired networks - main goal to provide wireless connection between two independent and fully-functional LAN nodes - downside is that it is easily attacked because it covers wide range of geo. locations

access point

- most important element in wireless network - interface between wired and wireless network - uses radio signals for connectivity - more flexible but less secure in comparison with regular Ethernet switch - enhance security and stop unauthorized access via authorization feature - can be configured to allow all users or selected users

Wireless Personal Area Network (WPAN)

- provides a wireless connection to devices that surround an individual's personal space. - examples: infrared and bluetooth - consumes less power, provides short-range communication, is low cost, and provides a connected communication of various devices in people's personal space.

wireless disadvantages

- speed > significantly slower than wired networking when transferring files over local area network - worsens if you have a busy network or signal strength is weaker than optimal - reliability > limited number of channels; if every channel is full, connections will slow down or fail to work > radios prone to interference giving unreliable network performance - security > poor, can be accessed via Wi-FI receiver, software, and signal reception > Wi-Fi protected access security protocol can be hacked - reduced management control > easier to connect unsanctioned devices, like personal tablets or cell phones consuming bandwidth > reduce ability to monitor employee activities during and have casual management interactions

Single Access Point WLANs

- usually a single access point system with an SSID of the network, i.e. home networks and public hotspots. - Client devices use this name to identify and join the wireless network. - name of the Wi-Fi network that you look for to join your device to.

rogue access point

- wireless access point that has either been installed on a secure company network without explicit authorization from a local network administrator, or has been created to allow a hacker to conduct a man-in-the-middle attack. - can pose a security threat to large organizations with many employees, because anyone with access to the premises can install (maliciously or nonmaliciously) an inexpensive wireless router that can potentially allow access to a secure network to unauthorized parties - target networks that do not employ mutual authentication (client-server server- client) and may be used in conjunction with a rogue RADIUS server, depending on security configuration of the target network