*3.3.5. Wireless fidelity (Wi-Fi)*

Wi-Fi (wireless fidelity) allows devices to communicate over a wireless signal, and contains any type of wireless local area network (WLAN) device supporting any of the following IEEE 802.11 specification versions: 802.11a, 802.11b, 80.2.11g, and 802.11n [7, 14]. Today, Wi-Fi is delivering the high-speed WLAN in-building connectivity to hotels, homes, airports, and cafes through the use of wireless access points (APs) [14]. Although encryption is considered optional in Wi-Fi, three techniques of encryption have been defined and applied to Wi-Fi to ensure security. These techniques are "wired equivalent privacy (WEP)," "WiFi protected access (WPA)," and "*IEEE 802.11i/WPA2"* [14]. To access a Wi-Fi network, Wi-Fi enabled devices (e.g., laptops) are needed, which can communicate wirelessly in any Wi-Fi equipped location [14].

#### *3.3.6. Bluetooth*

Bluetooth is a cheap communication technology, deployed for small distances (10–100 meters), that allows connection between devices, for example, laptops, PDAs, smartphones, printers, cameras, etc. without the need for cabling. Bluetooth is considered the main technology for creating a personal area network (PAN) to share data such as text, images, videos, and sounds, and it uses the IEEE 802.15.1 standard. Bluetooth allows users instantaneous connections between several devices and assures protection against interferences and safety in the sent information [15]. The Bluetooth technology operates in the ISM band, which is 2.45 GHz. Some standard Bluetooth applications include but are not limited to communication between hands-free device and a mobile phone or car radio, and transfer of files between devices [15]. Bluetooth can have some security risks, because it is an open system. Security can be implemented at the level of devices and services [15].

### *3.3.7. ZigBee*

and search for EPC data [12]. The EPC was basically designed to be stored on an RFID tag to identify a specific item and its associated data such as origination point and date of produc-

The barcode system uses a barcode scanner to interpret the value in the barcode label to obtain a unique code that is used for object identification [7]. Barcodes are "optical machinereadable labels attached to items to record information about them, and they are usually read by laser scanners" [7]. Three types of barcodes exist: *alpha numeric* used for encoding numbers and characters, *numeric* used for encoding pairs of numbers, and *2-dimensional*, which looks like squares or rectangles that contain many small, individual dots [7]. The disadvantage of this system is the line of sight requirement between the barcode and the reader [10, 13].

Internet protocol (IP), developed in 1970s, is considered main network protocol used for sending packets in the Internet [7]. There are two different versions of IP addresses: IPv4 (default version) and IPv6. IPv6 was developed to extend the number of available and supported IP

Wi-Fi (wireless fidelity) allows devices to communicate over a wireless signal, and contains any type of wireless local area network (WLAN) device supporting any of the following IEEE 802.11 specification versions: 802.11a, 802.11b, 80.2.11g, and 802.11n [7, 14]. Today, Wi-Fi is delivering the high-speed WLAN in-building connectivity to hotels, homes, airports, and cafes through the use of wireless access points (APs) [14]. Although encryption is considered optional in Wi-Fi, three techniques of encryption have been defined and applied to Wi-Fi to ensure security. These techniques are "wired equivalent privacy (WEP)," "WiFi protected access (WPA)," and "*IEEE 802.11i/WPA2"* [14]. To access a Wi-Fi network, Wi-Fi enabled devices (e.g., laptops)

Bluetooth is a cheap communication technology, deployed for small distances (10–100 meters), that allows connection between devices, for example, laptops, PDAs, smartphones, printers, cameras, etc. without the need for cabling. Bluetooth is considered the main technology for creating a personal area network (PAN) to share data such as text, images, videos, and sounds, and it uses the IEEE 802.15.1 standard. Bluetooth allows users instantaneous connections between several devices and assures protection against interferences and safety in the sent information [15]. The Bluetooth technology operates in the ISM band, which is 2.45 GHz. Some standard Bluetooth applications include but are not limited to communication between hands-free device and a mobile phone or car radio, and transfer of files between devices [15]. Bluetooth can have some security risks, because it is an open system. Security can be imple-

are needed, which can communicate wirelessly in any Wi-Fi equipped location [14].

tion [12].

*3.3.3. Barcode*

*3.3.4. Internet protocol (IP)*

142 Smartphones from an Applied Research Perspective

*3.3.5. Wireless fidelity (Wi-Fi)*

addresses [7].

*3.3.6. Bluetooth*

mented at the level of devices and services [15].

ZigBee technology was created and developed in 2001 by the ZigBee Alliance [7]. As defined in [16], ZigBee is "a low power, low cost, low data rate, and short range (around 100 meters), wireless network protocol based on the IEEE 802.15.4 standard" [16]. ZigBee is widely used in home automation, medical monitoring, industrial controls, and digital architecture [7]. ZigBee was developed to enhance the features of wireless sensor networks (WSNs) and is widely used for wireless home automation systems (WHASs); however, it has many related challenges such as resource constraints, low memory, limited battery, limited processing power, limited range, technological limitations related to the IEEE 802.15.4 standard, interferences with systems operating in the same free band, and internet connectivity, which is needed in WHAS for remote monitoring [16].

#### *3.3.8. Near-field communication (NFC)*

NFC is a short-range (theoretically 20 cm, but in most scenarios, typically 4 cm) wireless technology developed by "Philips and Sony companies" that works at the 13.56 MHz frequency and allows customers around the world to easily make transactions, connect electronic devices, and exchange digital content [7]. NFC technology is compatible with existing RFID infrastructure and contactless smart cards and uses the same standards such as ISO/IEC 14443 standard, which is one of its biggest advantages [17]. NFC has an easy and simple connection method, can work also in dirty environment, and does not require a line of sight for reading and executing transactions [7]. Some example applications of NFC include but are not limited to mobile payment such as Google Wallet, and mobile ticketing such as Oyster Card [17].

#### *3.3.9. Wireless sensor networks (WSNs)*

A WSN consists of hundreds to thousands of "sensor nodes" communicating with each other and passing data related to either "physical" or "environmental conditions" such as pressure, temperature, motion, location, sound, etc. [7, 18]. WSNs are used widely in IoT for many types of applications such as agriculture monitoring, patients monitoring, military applications, highway monitoring, civil and environmental engineering applications, forest fire, industrial automation, home control, building automation, etc. [18]. An example of the use of WSNs in healthcare is the use of sensors to monitor medication responses from a patient's body [7]. A key issue faced when designing a WSN network is energy efficiency, that is, designing for a "long network lifetime and limited network maintenance and deployment costs" [10]. A middleware system is needed to provide the multiple services required by WSN applications and allow for scalability, power saving, and quality of service (QoS) while designing WSN applications as suggested in [10].

#### *3.3.10. Actuators*

As defined in Ref. [7], an actuator is "a device that actuates or moves something; converting energy into motion or mechanical energy" [19, 7]. Typical applications of actuators are implemented in the industrial and manufacturing fields [7]. There are three types of actuators: *electrical actuators* are "AC and DC motors, stepper motors, and solenoids" [7]; *hydraulic actuators* "use hydraulic fluid to actuate motion" [7]; and *pneumatic actuators* "use compressed air to actuate motion" [7].
