Another difference between Bluetooth and Wifi that the limited number of devices has the ability to connect with other Bluetooth devices. On the other hand, Wifi allows access to a larger number of users.
Bluetooth is used when speed is not our concern and low bandwidth is allocated. Wifi offers high bandwidth as internet speed is an important factor.
|Hardware requirements||Bluetooth adapter on all devices that connect to each other.||Wireless adapter on all network devices and a wireless router.|
|Ease of use||Quite simple to use and switching from one device to another is simpler.||more complex and requires hardware and software configuration.|
|Range||10 meters||100 meters|
|Safety||Less secure in comparison||Security features are better. However, there are some risks.|
|Frequency range||2,400 GHz and 2,483 GHz||2, 4 GHz and 5 GHz|
|flexibility||Supports a limited number of users||Provides support for a large number of users|
|Modulation techniques||GFSK (Gaussian shift shifting)||OFDM (Orthogonal Frequency Division Multiplexing) and QAM (Quadrature Amplitude Modulation)|
Definition of Bluetooth
Bluetooth is an open (universal) specification for short-range wireless voice and data communications. The inventors of Bluetooth are Ericsson, Nokia, IBM, Toshiba and Intel have formed a special Internet Group (SIG) to expand the concept and develop a standard under IEEE 802.15 WPAN (Wireless Personal Area Network). Bluetooth is the first technology used for a short-range ad-hoc network designed for combined voice and data applications.
Compared to Wifi, Bluetooth has a slower data rate. However, it does have a built-in mechanism to aid application. Bluetooth is an ad-hoc personal area network that operates on unauthorized land owned by the user. Bluetooth SIG provides three application-based scenarios: 1. Cable replacement 2. Ad hoc personal network 3. Integrated access points (AP) for data / voice.
The Bluetooth topology is called the ad-hoc dispersed topology. It defines a small cell called Piconet which is a collection of connected devices in an ad-hoc way. There are four states
- M (Master) – can manage seven competitors and up to 200 active slaves in the piconet.
- S (Slave) – terminals that can take part in more than one piconet.
- SB (Stand by) – Looking forward to joining the piconet later in the meantime keeping its MAC address in it.
- P (Parked / pressed) – Looking forward to joining the piconet later and releasing its MAC address.
The modem FHSS (frequency hopping spread spectrum) it is used in the physical connection of Bluetooth with a nominal antenna power of 0 dBm (coverage 10 m) and works alternately at 20 dBm (coverage 100 m). Bluetooth jump speed of 1600 hops / second. Bluetooth assigns a specific frequency hopping format for each piconet.
Creating a Bluetooth connection involves two stages: request, page is connection . Active devices are assigned a LOVES 3 bit (Active Member Address), ai Parked devices are assigned a PMA a 8 bit (Parked Member Address), standby devices don't need an address.
- Sniff State – Slaves listens to the piconet at reduced rates.
- Hold state – Slave stops Asynchronous Connection Less (ACL) transmission but can exchange Synchronous Connection Oriented (SCO) packets.
- Park state – Slave releases his AMA.
- State of the page – AMA assigned (becomes master).
- Connected state – Listen, send and receive.
- Waiting state : listen periodically.
- Investigation status – To find out what other devices are there.
Bluetooth offers security of use and confidentiality of information. Use a random number a 128 bit, a MAC address a 48 bits of the device and two keys: Authentication (128 bit) e Encryption (8 to 128 bits). Three operating modes not I'm secure, service level is link level .
Definition of Wifi
Wifi (Wireless Fidelity) the name given by the Wi-Fi Alliance to the standard suite IEEE 802.11 . 802.11 set the initial standard for wireless local area networks (WLAN), the IEEE specifications are wireless standards that define an interface that it uses as a means of transmitting and receiving signals between a wireless client and a station or access point, as well as between client wireless networks.
The purpose of the 802.11 standards was to develop one layer MAC is PHY for wireless connectivity for permanent, portable and mobile stations within a local area. The IEEE 802.11 standard includes the following special features: 1. Provides an asynchronous and time-limited delivery service. 2. Supports the continuity of the service within large areas through the distribution system.
The requirements of IEEE 802.11 are: 1. Single MAC supports multiple PHY '. 2. Mechanisms to allow multiple networks overlapping in the same area. 3. Provisions to manage the interface from other ISM-based radios and microwave ovens. 4. Mechanisms to manage the "hidden" terminal. 5. Options to support limited time services. 6. Supply to manage access privacy and security.
There are two operating models or topologies defined in IEEE 802.11-
- Infrastructure mode : In this mode, the wireless network includes at least one access point (AP) generally connected to the wired network infrastructure and a collection of the wireless end station. Access controls encryption on the network and can connect or route wireless traffic to a wired ethernet network (or the Internet).
- Ad-hoc mode : In this mode, multiple 802.11 wireless stations interact directly with each other in the absence of an access point or any connection to a wired network. It is also called an independent Basic Service Set (IBSS) or peer-to-peer mode.
IEEE 802.11 has provisions for authentication and privacy. Two types of authentication supported by IEEE 802.11 are-
- Open system authentication – Default authentication scheme. The request frame sends the ID of the authentication algorithm for an open system. The response time sends the results of the request.
- Authentication with shared key : Provides more security. The request frame carries the ID of the authentication frames for the shared key using a 40-bit secret code shared between itself and IP. The second station sends a 128-byte challenge text. The first station sends the encrypted text as a response. The second station sends the authentication results. The privacy maintained in IEEE 802.11 by the specification WEP (wired equivalent privacy) . A key sequence constructed by a pseudorandom generator and a 40-bit secret key where the key sequence is simply an XOR-ed with the plain text message.
Key differences between Bluetooth and Wifi
- The low bandwidth requirement in Bluetooth while high in the case of Wifi.
- To establish the connection, via Bluetooth, a device requires a Bluetooth adapter. On the other hand, for the use of Wifi devices you need the wireless adapter and the router.
- Bluetooth is simple to use and switching between devices is simpler, while Wi-Fi technology is rather complicated and requires the configuration of hardware and software.
- The range of the radio signal provided by Bluetooth of 10 meters while of 100 meters in case of Wifi.
- The frequency range along which Bluetooth devices are supported from 2, 4 GHz to 2, 4483 GHz. Conversely, in Wifi the frequency range is from 2, 4 GHz to 5 GHz.
- Low energy consumption in Bluetooth, while high in Wifi.
- Bluetooth is less secure than Wifi and uses encryption and authentication keys. In contrast, Wifi has better security, although there are still some security issues. Wifi uses WEP (Wired Equivalency Privacy) and WPA (Wifi Protected Access).
Bluetooth and Wifi, both technologies have been invented to allow wireless communication between various devices. Although both have different purposes, it has its advantages and disadvantages.
Basically, Bluetooth is considered as short distance wireless communication while Wifi offers multiple privileges and long range, a large number of users and an inexpensive way to connect to the Internet.