Jawaharlal Nehru Technological University Hyderabad B.Tech III Year MOBILE COMPUTING Previous Question Paper (February - 2023 - R16)

Mobile computing is a generic term that describes the technology and infrastructure that enables the transmission of data, voice, and video via a computer or any other wireless-enabled device without having to be connected to a fixed physical link. It encompasses the ability to access network resources and services while in motion or while changing geographical locations.

Key characteristics of mobile computing include:

• Mobility: The capability of the user to move freely while maintaining a continuous connection to the network.
• Portability: The use of compact, lightweight devices such as smartphones, tablets, and laptops that are designed for easy transport.
• Connectivity: The reliance on wireless communication technologies, such as cellular networks (4G/5G), Wi-Fi, and Bluetooth, to facilitate data exchange.
• Context Awareness: The ability of the system to adapt to the user's current environment, such as location, time, and network availability.

In the GSM (Global System for Mobile Communications) architecture, Teleservices are value-added services that provide complete communication capabilities, including terminal equipment functions, to the user. These services rely on the underlying Bearer Services to transport data but include additional protocols for end-to-end communication. The primary teleservices include:

• Short Message Service (SMS): The most widely used teleservice, allowing for the transmission of alphanumeric messages up to 160 characters between mobile stations or between a mobile station and an external system. It supports both Mobile Originated (MO) and Mobile Terminated (MT) messaging.
• Cell Broadcast Service (CBS): A service that allows messages to be broadcast to all mobile users within a specific geographical area (a cell or group of cells). This is typically used for public information, weather alerts, or traffic updates.
• Telephony: The fundamental teleservice providing voice communication. It includes the necessary speech coding (e.g., Full Rate, Half Rate, or Enhanced Full Rate codecs) and signaling required to establish and maintain a voice call.
• Emergency Calls: A specialized teleservice that allows a user to connect to the nearest emergency service center by dialing a dedicated emergency number (e.g., 112). This service is prioritized and can be accessed even without a valid SIM card or if the mobile station is roaming.
• Facsimile (Group 3): A service that enables the transmission and reception of documents via the GSM network using standard fax protocols adapted for mobile environments.