In a Hard hand off a mobile station always communicates with just one base station.

A hard handoff is a handoff technique used with cellular networks that requires the user's connection to be entirely broken with an existing base station before being switched to another base station. ... A hard handoff is also known as a hard handover or break-before-make handover.

 The handover or handoff process is of major importance within any cellular telecommunications network. It is necessary to ensure it can be performed reliably and without disruption to any calls.

SOft Handover:- When mobile ( in Call0 switches to a new sector/cell which is on the same frequency then it is called a soft handover. If the "new" sector is also from the same BTS then it is called a softer handover. UMTS networks omplements all types (Hard/Soft/Softer) of handovers.

Different approaches are proposed and applied in order to achieve better handoff service. The principal parameters used to evaluate handoff techniques are: forced termination probability and call blocking probability. ... Handoff (or handover) process is transferring an active call from one cell to another.

A special type of device which uses an ordinary telephone with a computer is Acoustic couple

In telecommunications, an acoustic coupler is an interface device for coupling electrical signals by acoustical means—usually into and out of a telephone.

Ethernet modems that plug into the network card in the computer, and wireless modems that connect to a computer using a wireless LAN (WLAN). Some modems offer dual Ethernet and USB connection. There are also routers with integrated ADSL modem.

A TTY is a special device that lets people who are deaf, hard of hearing, or speech-impaired use the telephone to communicate, by allowing them to type messages back and forth to one another instead of talking and listening.

For reliability it does not matter. So all of above are technology is more reliable.

Mechanical Technology. Nearly every product includes mechanical components that must be created by a mechanical designer. ... The mechanical designer of today requires knowledge in many areas including mechanical drafting, computer-aided drafting and design, machine shop, robotics and machine components.

A mechanical computer is built from mechanical components such as levers and gears, rather than electronic components. The most common examples are adding machines and mechanical counters, which use the turning of gears to increment output displays.

Computer Electronics Technology is an associate degree program that prepares you for a technical career in the computer field. You will learn to operate, install, configure, upgrade and maintain microcomputers, peripheral devices and network hardware.

A  Mobile switching centre is a computerized centre, that is responsible for connecting calls, recording call information and billing.

A mobile switching center (MSC) is the centerpiece of a network switching subsystem (NSS). The MSC is mostly associated with communications switching functions, such as call set-up, release, and routing. The Mobile Switching Centre (MSC) is a telephone exchange that makes the connection between mobile users within the network, from mobile users to the public switched telephone network and from mobile users to other mobile networks.

BSC. The Base Station Controller (BSC) is in control of and supervises a number of Base Transceiver Stations (BTS). The BSC is responsible for the allocation of radio resources to a mobile call and for the handovers that are made between base stations under his control. Other handovers are under control of the MSC.

Base Transciever Station (BTS) The BTS is a telecoms infrastructure used to facilitate wireless communication between subscriber device and telecoms operator network. The subscriber device can be mobile phone, wireless internet devices while the operator network could be a GSM, CDMA or TDMA platform.

PTN stands for Public Telephone Network.

The public switched telephone network (PSTN) is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators, providing infrastructure and services for public telecommunication.

How does the Public Switched Telephone Network work? PSTN uses circuit switching to allow users to make landline telephone calls to one another. The call is placed after it is routed through multiple switches. These switches are found in a central office (CO) or in a wire center.

PSTN (public switched telephone network) is the world's collection of interconnected voice-oriented public telephone networks, both commercial and government-owned. It's also referred to as the Plain Old Telephone Service (POTS).

GPS is not used for voice communication.

An early satellite-based system dubbed TRANSIT was up and running as early as 1960, with more refined and precise versions involving multiple satellites in general military use by the early 1980s (pictured, right). But it wasn't until 2000 that precision GPS navigation became open to the public.

The Global Positioning System (GPS) is a network of about 30 satellites orbiting the Earth at an altitude of 20,000 km. ... Once it has information on how far away at least three satellites are, your GPS receiver can pinpoint your location using a process called trilateration.

During Labor Day weekend in 1973, a meeting of about twelve military officers at the Pentagon discussed the creation of a Defense Navigation Satellite System (DNSS). It was at this meeting that the real synthesis that became GPS was created.

GPS (or global positioning system), is a satellite-based navigation system made up of a network of 24 satellites orbiting the earth at all times. This system, when the proper signals are received, allows a user to tell where they are located.

Dual tone multi frequency are not telephony services supported by GSM

DTMF ( Dual Tone Multiple Frequency ) is used to send to signals for button presses on telephones. The data is typically sent over voice channels and so in order to distinguish from human voice , when you hit a button the phone generates two tones of different frequencies - one lower frequency and one high frequency.

DTMF (dual tone multi frequency) is the signal to the phone company that you generate when you press an ordinary telephone's touch keys. In the United States and perhaps elsewhere, it's known as "Touchtone" phone (formerly a registered trademark of AT&T).

GSM is a globally accepted standard for digital cellular communications. GSM uses narrowband Time Division Multiple Access (TDMA) for providing voice and text based services over mobile phone networks.

Wireless adaptors are Always needed to connects to wireless networks.

A wireless adapter is a hardware device that is generally attached to a computer or other workstation device to allow it to connect to a wireless system. Before the advent of consumer devices with built-in Wi-Fi connectivity, devices required the use of wireless adapters to connect to a network.

A USB Wi-Fi adapter eliminates the need to hardwire the computer to a router or other network device. ... The adapter receives signals from a wireless router or other wireless device and translates the signal so the computer user can access the Internet any time they are in range of a Wi-Fi hotspot or wireless network.

A high-speed wireless network card that is used to access a network through a USB port on a computer or laptop. Most wireless USB LAN adapters look like small USB flash drives and usually are based on the 802.11g standard which provides a data rate up to 54-Mbps in a wireless LAN environment.

While wireless LANs refer to any local area network (LAN) that a mobile user can connect to through a wireless (radio) connection; Wi-Fi (short for "wireless fidelity") is a term for certain types of WLANs that use specifications in the 802.11 wireless protocol family. ... Differences between Wi-Fi, WLAN and WiMax.

Bluetooth is Short-range radio technology used to perform synchronization between net devices and other devices.

A Bluetooth technology is a high speed low powered wireless technology link that is designed to connect phones or other portable equipment together. It is a specification (IEEE 802.15.1) for the use of low power radio communications to link phones, computers and other network devices over short distance without wires.

Bluetooth technology is a short-range wireless communications technology to replace the cables connecting electronic devices, allowing a person to have a phone conversation via a headset, use a wireless mouse and synchronize information from a mobile phone to a PC, all using the same core system.

The Bluetooth RF transceiver (or physical layer) operates in the unlicensed ISM band centered at 2.4 gigahertz (the same range of frequencies used by microwaves and Wi-Fi). The core system employs a frequency-hopping transceiver to combat interference and fading.

Cellular technology is designed to provide communication between two moving units called mobile station.

Cellular communication is designed to provide communications between two moving units, or between one mobile unit and one stationary phone or land unit (PSTN). ... Each base station is controlled by a switching office, called a mobile switching center (MSC).

Cellular technology is what mobile phone networks are based on, and it's the technology that gave mobile phones the name “cell phones”. Cellular technology basically refers to having many small interconnected transmitters as opposed to one big one.

A cellular network or mobile network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, but more normally three cell sites or base transceiver stations.

Cellular (cell) phones operate with radio frequencies, a form of electromagnetic energy located on the electromagnetic spectrum between FM radio waves and the waves used in microwave ovens, radar, and satellite stations. Cell phones do not emit ionizing radiation, the type that damages DNA.

Video text is a combination of Computer technology

An example of computer technology is the development of a software program that allows people to accomplish work at home which has been automatically assigned from computers at their job location. YourDictionary definition and usage example.

Technical terms are an essential part of all technical and scientific writing. Each field and specialty typically uses a vocabulary that relays a variety of specialized concepts by means of technical language.

Technical terms are an essential part of all technical and scientific writing. Each field and specialty typically uses a vocabulary that relays a variety of specialized concepts by means of technical language.

An IT career involves installing, organizing and maintaining computer systems as well as designing and operating networks and databases. Computer science is focused entirely on efficiently programming computers using mathematical algorithms.

GPRS scheme allows mobile stations to send and receive IP packet in a cell running voice system.

General packet radio service (GPRS) is a packet-based wireless data communication service designed to replace the current circuit-switched services available on the second-generation global system for mobile communications (GSM) and time division multiple access (TDMA) IS-136 networks.

Another 2.5G scheme is GPRS (General Packet Radio Service), which is an overlay packet network on top of D-AMPS or GSM. It allows mobile stations to send and receive IP packets in a cell running a voice system. When GPRS is in operation, some time slots on some frequencies are reserved for packet traffic.

General Packet Radio Service (GPRS) is a packet oriented mobile data standard on the 2G and 3G cellular communication network's global system for mobile communications (GSM).

GPRS has been called the 2.5 G system. This is because it was developed after the 2G cellular networks and before the 3G systems that are currently showing up on the market today. GPRS is still widely used across the globe today. General Packet Radio Service works by allowing data to be stored into 'packets'.

CDMA is a multiple access method in which one channel carries all transmission simultaneously.

FDMA versus TDMA versus CDMA. This page on FDMA versus TDMA versus CDMA provides difference between FDMA,TDMA and CDMA technologies. ... FDMA- Frequency Division Multiple Access, here entire band of frequencies is divided into multiple RF channels/carriers. Each carrier is allocated to different users.

U.S. Narrowband Spread Spectrum (IS-95): CDMA/FDD. 4) Space Division Multiple access (SDMA) FDMA,TDMA and CDMA are the three major multiple access techniques that are used to share the available bandwidth in a wireless communication system.

Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel.

Telephone companies use FDM

Frequency-division multiplexing. In telecommunications, frequency-division multiplexing (FDM) is a technique by which the total bandwidth available in a communication medium is divided into a series of non-overlapping frequency bands, each of which is used to carry a separate signal.

Frequency Division Multiplexing (FDM) is a networking technique in which multiple data signals are combined for simultaneous transmission via a shared communication medium. FDM uses a carrier signal at a discrete frequency for each data stream and then combines many modulated signals.

Fused deposition modeling (FDM) is an additive manufacturing (AM) technology commonly used for modeling, prototyping, and production applications as trademarked by Stratasys Inc.. It is one of the techniques used for 3D printing.

The word FIP stands for File Translate Protocol.

A voicemail system (also known as voice message or voice bank) is a computer-based system that allows users and subscribers to exchange personal voice messages; to select and deliver voice information; and to process transactions relating to individuals, organizations, products and services, using an ordinary telephone. The term is also used more broadly to denote any system of conveying a stored telecommunications voice messages, including using an answering machine. Most cell phone services offer voice-mail as a basic feature

Voice mail offers many communications advantages over answering machines, including the ability for users to check their messages remotely. ... The machine replays an analog or digital recording of a message, to which the user can listen by pressing a button.

WLL( Wireless local loop) is the use of wireless communications connection for delivery plain old telephone service or internet access to telecommunications customers. such as GSM.

Data are sending by email for security purpose in encrypted form.

End-to-end email encryption is a method of transmitting data where only the sender and receiver can read email messages. With end-to-end email encryption, the data is encrypted on the sender's system. Only the intended recipient will be able to decrypt and read it.

Email encryption involves encrypting, or disguising, the content of email messages in order to protect potentially sensitive information from being read by anyone other than intended recipients. Email encryption often includes authentication.

WAP allows wireless mobile devices to access the Internet and its services such as the Web and e-mail.

Wireless Application Protocol (WAP) is a technical standard for accessing information over a mobile wireless network. A WAP browser is a web browser for mobile devices such as mobile phones that uses the protocol. Introduced with much hype in 1999, WAP achieved some popularity in the early 2000s, but by the 2010s it had been largely superseded by more modern standards. Most modern handset internet browsers now fully support HTML, so they do not need to use WAP markup for web page compatibility, and therefore, most are no longer able to render and display pages written in WML, WAP's markup language.

Before the introduction of WAP, mobile service providers had limited opportunities to offer interactive data services, but needed interactivity to support Internet and Web applications such as email, stock prices, news and sports headlines. The Japanese i-mode system offered another major competing wireless data protocol.

Voicemails is a personal security code for GSM (global system for mobile communication) subscribers.

GSM (global system for mobile communication) services are a standard collection of applications and features available to mobile phone subscribers all over the world. The GSM standards are defined by the 3GPP collaboration and implemented in hardware and software by equipment manufacturers and mobile phone operators. 

GSM provides recommendations, not requirements. The GSM specifications define the functions and interface requirements in detail but do not address the hardware.

A voicemail system is a computer-based system that allows users and subscribers to exchange personal voice messages; to select and deliver voice information; and to process transactions relating to individuals, organizations, products and services, using an ordinary telephone. The term is also used more broadly to denote any system of conveying a stored telecommunications voice messages, including using an answering machine.

A simple protocol used for fetching e-mail from a remote mailbox is Post Office Protocol which is defined in RFC 1084.

Post office protocol (POP) is an application layer internet standard protocol used by e-mail clients to retrieve e-mail from a server in an internet protocol(IP) network.

Post office protocol (POP) is a message access protocol that enables the client to fetch an e-mail from the remote mail server.

A request for comments (RFC) is a formal document from the internet engineering task force ( IETF ) that is the result of committee drafting and subsequent review by interested parties.

Mobile computers and personal digital assistants (PDAs) are the examples of wireless network.

Personal digital assistant:-

Personal digital assistant is a term for a small, mobile, handheld device that provides computing and information storage and retrieval capabilities for personal or business use, often for keeping schedules, calendars and address book information handy.

Mobile computers:-

Mobile computing is human computer interaction by which a computer is expected to be transported during normal usage, which allows for transmission of data, voice and video.

Wireless network:-

A wireless network is a computer network that uses wireless data connections between network nodes.

In recent years general packet radio service (GPRS) has been deployed to give IP connectivity to GSM users.

General packet radio services (GPRS) is a packet-based wireless communication service that promises data rates from 56 up to 114 Kbps and continuous connection to the internet for mobile phone and computer users. The higher data rates allow users to take part in video conferences and interact with multimedia Web sites and similar applications using mobile handheld devices as well as notebook computers.

General Packet Radio Service (GPRS) is a packet oriented mobile data standard on the 2G and 3G cellular communication network's global system for mobile communications(GSM).

video conferencing used in real time system.

video conferencing system:-

Videoconferencing (or video conference) means to conduct a conference between two or more participants at different sites by using computer networks to transmit audio and video data. For example, a point-to-point (two-person) video conferencing system works much like a video telephone.

Real-time communication is a means of sharing information and interacting with people in different locations via Internet connections, just as if you were talking to each other face-to-face. Apart from audio-only conference call, video conferencing is also one kind of live teleconferencing communications. The advantages of video conference in real-time communication are obvious, and it has been widely applied to host a virtual video meeting or online training in almost every industry.

A transmission in which receiver receives the data simultaneously as it is relayed is called Real-time transmission.

Real Time Transmission:- When you are sending a fax, the machine will scan the document into the memory before sending it. Sometimes, we may want to send an important document immediately, without waiting for memory transmission.

Global system for mobile communication:-

GSM (Global system for mobile communication) is a standard developed by the European telecommunications standards institute (ETSI) to describe the protocols for second-generation digital cellular networks used by mobile devices such as tablets.

GSM uses a variation of time division multiple access (TDMA) and is the most widely used of the three digital wireless telephony technologies: TDMA, GSM and code-division multiple access (CDMA). 

Piggy backing is a technique for Flow control.

The receiver waits until its network layer passes in the next data packet. The delayed acknowledgement is then attached to this outgoing data frame. This technique of temporarily delaying the acknowledgement so that it can be hooked with next outgoing data frame is known as piggybacking.

Piggybacking is a technique used for efficient utilization of bandwidth. The acknowledgment for previous segment is sent along with the data request/transfer of current segment.