People get confused because many small technology appliances made for home use are actually several devices in one. One of my pet peeves on is when people use the term "Wireless Router" to describe a device that is both a wireless access point and a router.
What is a wireless access point?
A Wireless Access Point (WAP) is a networking hardware device which, as the name describes, gives you wireless access to your LAN (local area network).You have a wired connection, an RJ 45 port in your wall, that is wired access. You want to convert that to a wireless access point. It has nothing to do with routing or switching.
Depending on the type and complexity of the network, the WAP (Wireless access point) could be something simple similar to a network switch which is simply a management device that connects the wireless part of the network to the network as a whole.
In a very small home network the WAP could be part of the router where one appliance has multiple features to in in the management of the network. What you might call a router in your home may actually be a router, and a switch, and a wireless access point.
What are wireless access points used for?
In the business world Wireless Access Points (WAP) are fairly common. On a business network your desktop computers (workstations) are connected via wire, but you probably have several WAPs (Wireless Access Points) for your laptop users.
If you are a visitor to a business network you may notice WAPs set up for office staff as well as visitors. This is becoming very common. You see this in government locations, perhaps even where you get your car serviced you can take your notebook into a lounge where you can use a "guest network" to connect to the internet.
Let's say you have a large home, and it is wired for data, as in it has ethernet ports through out your home. You have a wired connection, an RJ 45 port in your wall, that is wired access. You want to convert that to a wireless access point. It has nothing to do with routing or switching. In wireless communications the "media" is a type of radio wave that communicates from your wireless adapter to the Wireless Access Point.
If your home office is in the basement, and that is the location of your current connection device (router, switch, wireless access point) where everything plugs in. On the second floor of your house you have an ethernet port in your bedroom, but you want to use a tablet to surf the web, or perhaps use some internet appliance with your bedroom television. The signal from the wireless access point in your basement is too weak. You don't need to purchase another device that is a router and switch and WAP, all you need is the WAP (wireless access point). So you simply buy a device that is ONLY a WAP, and plug it into your ethernet connection.
What is a wireless adapter?
Comparing a wireless network to a wired one, in a wired network your computer workstation has a NIC (Network Interface Card) which in a typical Ethernet network has an RJ-45 jack on it where the network cable plugs into your computer. From your computer the other end of the network cable plugs into some other type of device such as a switch or router, where traffic on your network is managed and distributed. On a wireless network the wireless adapter takes the place of the NIC.
How do I use ad hoc on a wireless network?
Ad hoc networks refer to networks created for a particular purpose. They are often created on-the-fly and for one-time or temporary use. If you don’t have a crossover cable to connect two notebooks or netbooks you can use their wireless capabilities to exchange files between without the need for any other than the computer itself. Instead of configuring your wireless adapter to connect to a wireless access point or router, you configure your wireless adapter to connect to another computer.
In the wireless world an ad hoc network is the equivalent of a peer to peer network. In very small home networks, you may have two or three computers where you share resources between them, and to do so you set up a "peer to peer" network. Much like peer to peer networks in the wired world, ad hoc networks have management and security issues beyond that of the typical infrastructure network.
If your computer never leaves your house, having it set up to share files with another computer in your home may not be an issue you have to worry about. On the other hand, if you travel with your computer, having ad hoc set up on your portable computer could create issues. Wireless devices in ad hoc mode offer minimal security against unwanted incoming connections, and there is a large security risk in using an ad hoc connection to an unknown computer, as you are exposing your computer to file sharing with strangers.
In some cases computers in public are purposely set up to look for and connect to other computers in ad hoc mode in order to steal information from them. When using your computer in public hotspots you typically will be looking for a Wireless Network Connection, and ignore an attempt to connect with a strange computer using an ad hoc connection.
What is a Wi-Fi access point?
The term Wi-Fi is often used as a synonym for wireless local area network (WLAN), but the terms "wireless access point" and "Wi-Fi" are not synonyms. Specifically the term "Wi-Fi" is a trademark of a trade association known as the Wi-Fi Alliance. The marketing company Interbrand, known for creating brand names, was hired to create a brand name to market the new technology, and the name Wi-Fi was chosen. The term "Wi-Fi" with the dash, is a trademark of the Wi-Fi Alliance.
From a technical perspective WLAN technology is defined by the Institute of Electrical and Electronics Engineers (IEEE). IEEE 802 refers to a family of IEEE standards dealing with networks carrying variable size packets, which makes it different from cell phone based networks, 802.11 is a subset of the family specific to WLAN technology. Victor "Vic" Hayes was the first chair of the IEEE 802.11 group which finalized the wireless standard in 1997.
In computer networking you would use the term Wireless Access Point (WAP) rather than Wi-Fi access point. A Wireless Access Point (WAP) is a device that offers, as the name suggests, wireless access to a wireless local area network (WLAN). While cell phone technology is often discussed as a form of wireless networking, it is not the same as the wireless local area network (WLAN) technology discussed here.
This link takes you to the 802.11 specification that contains all the geek speak on how it works. --> IEEE-SA -IEEE Get 802 Program