Wireless network - Wikipedia
The version control table will show the published update date and .. filtering out categories of sites deemed inappropriate for the workplace There MUST be a robust boundary (with network security enforcing components). Community Wireless Networks can be designed in many ways. To help you There are three major “modes” a Wi-Fi device can use. In discussing these modes and the examples below, several types of devices are used. What are the roles and relationships between the different colored nodes in the networks?. Because there are so many types of wireless networks, it is not feasible for this .. WLAN technology and the WLAN industry date back to the mids when the the range extends beyond the physical boundaries of the building's walls, .
Types of wireless networks[ edit ] Wireless PAN[ edit ] Wireless personal area networks WPANs connect devices within a relatively small area, that is generally within a person's reach. The use of spread-spectrum or OFDM technologies may allow users to move around within a local coverage area, and still remain connected to the network.
Products using the IEEE Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths.
Types of Wireless Networks
It is often used in cities to connect networks in two or more buildings without installing a wired link. Wireless ad hoc network[ edit ] A wireless ad hoc network, also known as a wireless mesh network or mobile ad hoc network MANETis a wireless network made up of radio nodes organized in a mesh topology. Each node forwards messages on behalf of the other nodes and each node performs routing. Ad hoc networks can "self-heal", automatically re-routing around a node that has lost power.
Various network layer protocols are needed to realize ad hoc mobile networks, such as Distance Sequenced Distance Vector routing, Associativity-Based RoutingAd hoc on-demand Distance Vector routingand Dynamic source routing. These networks can be used to connect branch offices of business or as a public Internet access system. The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.
- Wireless network
- Types of Wireless Networks
- IEEE 802.11
A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photovoltaic solar panels or wind systems they can be stand alone systems. In a cellular network, each cell characteristically uses a different set of radio frequencies from all their immediate neighbouring cells to avoid any interference.
When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers e. Although originally intended for cell phones, with the development of smartphonescellular telephone networks routinely carry data in addition to telephone conversations: The GSM network is divided into three major systems: The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred to where it needs to go.
GSM is the most common standard and is used for a majority of cell phones. Sprint happened to be the first service to set up a PCS. The newer GSM networks are replacing the older system. Global area network[ edit ] A global area network GAN is a network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc.
The key challenge in mobile communications is handing off user communications from one local coverage area to the next. Different uses[ edit ] Some examples of usage include cellular phones which are part of everyday wireless networks, allowing easy personal communications.
Another example, Intercontinental network systems, use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively as well. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world. General[ edit ] In a general sense, wireless networks offer a vast variety of uses by both business and home users.
Each wireless technology is defined by a standard that describes unique functions at both the Physical and the Data Link layers of the OSI model.The Christian Dating Boundaries No One Talks About
These standards differ in their specified signaling methods, geographic ranges, and frequency usages, among other things. Such differences can make certain technologies better suited to home networks and others better suited to network larger organizations. The use of this technology also gives room for expansions, such as from 2G to 3G and, 4G and 5G technologies, which stand for the fourth and fifth generation of cell phone mobile communications standards. As wireless networking has become commonplace, sophistication increases through configuration of network hardware and software, and greater capacity to send and receive larger amounts of data, faster, is achieved.
Now the wireless network has been running on LTE, which is a 4G mobile communication standard. Access Points cannot connect to Ad-Hoc Mesh devices wirelessly: Wireless devices in networks Treat the three types of roles above - Clients, Access Points, and Ad-Hoc nodes - as the building blocks for large networks. Below are several examples that demonstrate how devices configured for different roles can be used. Access Point - Home or Office network Wireless networks used in your home or office are generally a combination of a router and a wireless Access Point AP.
In the diagram above: In many home networks, or small office networks, the router and AP may be combined into a single device. This is usually just called a wireless router. In large office scenarios, there may be several AP devices spread throughout the building to provide more even wireless coverage, connected back to the router through long Ethernet cables.
Point to Point link - Long Distance Connections Wireless networks can be used to connect distant buildings or areas. It usually requires very focused antennas - such as a dish antenna - that can send a narrow beam in a specific direction. This is discussed in Learn Wireless Basics - so go there for more details on how that works. The name describes the concept: This requires two wireless devices: In the example below, two wireless devices are configured to create a point-to-point link.
Omnidirectional Access Point and Client Link 1 represents computers connected with Ethernet cables to the wireless devices. These computers are connected to each other over the Point-to-Point link. This could look like the building-to-building connection, as shown below: Long-distance directional Access Point and Client Link Here we have another example of a point-to-point link, but where the routers have dish antennas for greater link distance.
This could look like the network below, where an AP mounted on a tower is able to connect with a Client device in a home very far away, since the dishes are facing one another.
802.11 Wireless Networks: The Definitive Guide, 2nd Edition by Matthew S. Gast
In both of these examples, there are just two wireless devices linked together - and the antennas determine the range at which they can connect. The more focused the signal, the further the point-to-point link can reach.
As the distance between the devices grow, it is more an more important to focus the signal with antennas - at both ends of the connection. Otherwise one end may hear the other, but not be loud enough to be heard! Point to MultiPoint - Wireless Internet Service Provider model If we combine the two principles used in the networks above - many client devices connecting to an Access Point, and more powerful antennas used for outdoor devices to create longer links - we can create Point to Multipoint networks.
Instead of running cables around a neighborhood or town, they put up one or more powerful Access Points on a tall building or tower. The diagram below demonstrates one model for how this works. There is a powerful Access Point mounted on a high building, and several nearby buildings with rooftop wireless Client devices: Connected to each of the Client devices is an indoor router or Access Point, which allows users to connect their computers, laptops, tablets, or smartphones to the WISP network.
Mesh - Neighbor-to-neighbor Networks A mesh network takes the principle of Point-to-Multipoint, and extends it to the idea of every node connecting to every other node in range. For more information on how this principle works, see the Introduction to Mesh document. These nodes will share all resources connected to them such as local servers hosting applications and connections to the Internet.
They can also be connected to computers, Access Points, or routers inside the buildings so users can access the resources anywhere on the network. These nodes are receiving Internet access from Mesh Node B. They may be connected to different devices inside the building.
Hybrid Networks When designing and building town or community-sized networks, it may be difficult or impossible to use a single method to connect everyone. For instance, a single Point-to-Multipoint network may not cover an entire community. Mesh nodes can be used to extend client sites to nearby buildings. Point-to-point connections can bridge longer distances and join several disconnected networks together. In the diagram below, we can see an example of a hybrid network.
There is no single example that can cover all of the possible uses for a network! In the activity that follows, you will explore the different ways to build a network by working through scenarios. One last note before we move on to the activity - in the examples above, and in the activity that follows, the diagrams focus on building networks across rooftops or from building to building.
This is generally the best way to build networks that cover neighborhoods, towns, or communities. Keep in mind that these rooftop routers may not provide connections to users on the ground, or in buildings.
A good way to provide these connections is by attaching Access Points to an Ethernet port on the rooftop router. This indoor Access Point can be set up to use the rooftop network as the source of connections to the Internet, or to provide access to applications and servers on the network.