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Right choice is (a) TIU

Easy explanation: The function of TIU (Trunk interface unit) is to accept information from the PSTN. TIU acts as the physical layer and TRANSFORMS the standard format of the PSTN into the WIRELESS ACCESS physical layer.

Correct option is (d) PACKET RESERVATION multiple access

Explanation: Transmission protocol, PRMA stands for packet reservation multiple access. PRMA is a time division MULTIPLEX (TDM) BASED multiple access protocol that allows a group of spatially DISPERSED terminals to transmit packet voice and low bit rate data over a common channel.

Correct ANSWER is (a) ADVANCED INTELLIGENT network

Best explanation: The concept of PCS/PCN is based on an advanced intelligent network (AIN). The mobile and fixed networks will be integrated to provide universal access to the network and its databases.

Right CHOICE is (b) False

Explanation: The objective of personal communication SYSTEMS (PCS) or personal communication networks (PCNs) is to provide ubiquitous wireless communications coverage, enabling USERS to access TELEPHONE network and Internet.

The correct choice is (a) Packet switching TECHNIQUES

The EXPLANATION: Packet switching techniques are used for transmission of packets in the cellular switched ARCHITECTURE. Packet switching is attractive for wireless networks because the addresses and other INFORMATION in packet headers make it possible for dispersed network elements to respond to a mobile user without intervention central CONTROLLERS.

Right option is (B) False

Explanation: AIN (advanced intelligent network) allow its USERS to have a single telephone NUMBER to be used for both wireless and WIRELINE services.

Right choice is (a) MTP

The EXPLANATION: The SS7 user part includes the ISDN user part (ISUP), the transaction capabilities APPLICATION part (TCAP) and operations maintenance and ADMINISTRATION part (OMAP). The telephone user part (TUP) and the DATA user part (DUP) are included in the ISUP.

Right choice is (d) Application

The explanation: The TRANSACTION capabilities application PART in SS7 refers to the application layer which invokes the SERVICES of the SCCP and the MTP in a hierarchical format. TCAP is CONCERNED with REMOTE operations.

Right OPTION is (b) MTP level 2

Explanation: Signalling data link functions are PROVIDED by MTP level 2. They correspond to the SECOND layer in the OSI REFERENCE model and provide a reliable link for the transfer of traffic between two directly connected signalling points.

Right answer is (b) False

Easy explanation: Packet switching TECHNOLOGY will have more advantages for PCS/PCN than circuit switching. PCS is required to SERVE a wide range of SERVICES including voice, data, e-mail and DIGITAL video.

The correct answer is (a) TIU

Easiest EXPLANATION: PTI (PERMANENT terminal identifier) is the address of TIU. It is the address from where he call is ORIGINATED.

Right OPTION is (B) VCI

To explain I would say: VCI (VIRTUAL CIRCUIT identifier) is the information contained in the packet header of TIU. It is used to identify the route through which the transmission will take place.

Right answer is (a) MTP

Easiest explanation: The function of the MTP is to ensure that SIGNALLING traffic can be TRANSFERRED and DELIVERED reliably between the END users and the network. MTP is provided at three levels.

The CORRECT choice is (a) Layer protocol used in CDPD

For EXPLANATION I would say: MDLP (Mobile data link protocol) is a LOWER layer protocol of CDPD. It is used to convey information between data link layer entities (layer 2 DEVICES) across the CDPD AIR interface.

Right answer is (a) Cell

To EXPLAIN I would say: The data unit of ATM is cell. They are routed based on header information in each unit (CALLED a label) that identifies the cell as belonging to a specific ATM virtual CONNECTION.

The correct CHOICE is (d) ARQ

Best explanation: The control field defines FUNCTIONS such as TRANSFER of acknowledgments, automatic repeat requests (ARQs), and packet SEQUENCING. The information field contains user data. And the final field is the FRAME check sequence field or the CRC (cyclic redundancy check).

The CORRECT answer is (c) Beginning

To explain I would SAY: The header specifies the beginning of a new packet. It contains the source address, packet SEQUENCE number, and other routing and BILLING information.

The correct answer is (a) Touchstar

Easy explanation: Touchstar is also KNOWN as CLASS. It is a GROUP of switch controlled services that PROVIDE its users with CERTAIN call management CAPABILITIES.

Right choice is (c) Duplex

For explanation I would say: Each CDPD channel is duplex in nature. The forward channel serves as a beacon and transmits data from the PSTN side of the network, while the reverse channel LINKS all MOBILE users to the CDPD network and serves as the access channel for each subscriber.

The correct OPTION is (B) False

Best explanation: The X.25 protocol does not specify particular data rates or how PACKET switched networks are implemented. Rather, X.25 PROVIDES a series of standard FUNCTIONS and formats which give structure to the design of the software.

The CORRECT choice is (c) X.25

The best I can explain: X.25 was DEVELOPED by CCITT (now ITU-T) to provide STANDARD CONNECTIONLESS network access (packet switching) protocols for the three layers (layer 1, 2 and 3) of the open systems INTERCONNECTION (OSI) model.

Right OPTION is (b) False

The best explanation: IS-41 relies on a FEATURE of AMPS called autonomous registration. Autonomous registration is a PROCESS by which a mobile NOTIFIES a serving MSC of its presence and location.

Correct option is (c) LOWEST THREE

The best I can EXPLAIN: The lowest three layers of the OSI model are handled in SS7 by the network service PART (NSP) of the protocol. NSP is made up of three message transfer parts (MTPs) and the SIGNALLING connection control part (SCCP) of the SS7 protocol.

Right option is (b) False

For EXPLANATION: The second signalling component of ISDN, network signalling is governed by the SS7 suite of PROTOCOLS. For WIRELESS communication systems, the SS7 protocols within ISDN are CRITICAL to providing backbone network connectivity between MSCs throughout the world.

The correct choice is (B) Virtual circuit routing

To elaborate: Connection oriented services are also called virtual circuit routing. In connection oriented routing, the COMMUNICATIONS PATH between the message source and destination is fixed for the ENTIRE duration of the message.

Correct option is (d) Switching END points

For explanation: The MSC provides subscriber access to the PSTN via the switching end points (SEPs). The SEP implements a stored PROGRAM control switching SYSTEM known as the service control point (SCP).

The correct choice is (a) FIXED length

The explanation is: CDPD transmissions are carried out USING fixed length blocks. User data is protected using a Reed-Solomon (63, 47) block CODE with 6 bit SYMBOLS.

The correct OPTION is (B) Circuit switching

For EXPLANATION: Wireless data networks are not supported by circuit switching. It is due to their short, bursty transmissions which are often followed by periods of inactivity. Circuit switching is BEST suited for dedicated VOICE only traffic.

The correct option is (d) DECT

Explanation: DECT is an example of SECOND generation cordless telephone standard which ALLOWS each cordless PHONE to communicate with any number of base stations. In DECT, the base stations have greater control in TERMS of switching, signalling, and CONTROLLING handoffs.

Correct answer is (b) MSC

Explanation: To provide wireless communication WITHIN a particular geographic REGION, an INTEGRATED NETWORK of base stations must be deployed to provide sufficient radio coverage to all mobile users. The base station, in turn must be connected to a central HUB called MSC (mobile switching center).

Right option is (b) CCS

The BEST explanation: ISDN is a COMPLETE network framework designed around the concept of common channel signalling. While telephone users throughout the world rely on the PSTN to carry conventional voice TRAFFIC, new end-user data and signalling services can be PROVIDED with a parallel, dedicated signalling network.

Right choice is (a) SIGNALLING transfer points

The best I can explain: The signalling transfer point (STP) controls the switching of messages between nodes in the CCS network. For higher reliability of transmission, SEPs are required to be connected to the SS7 network VIA at least two STPs.

Correct answer is (c) B channels

For explanation I would say: The ISDN INTERFACE is divided into three different TYPES of channels. Information bearing channels called bearer channels (B channels) are used exclusively for END USER traffic (voice, DATA and video).

Right OPTION is (a) Datagram services

Explanation: CONNECTIONLESS services are ALSO called datagram services. In a connectionless service, a call set up PROCEDURE is not required at the beginning of a call, and each message BURST is treated independently by the network.

The CORRECT answer is (a) MAHO

To EXPLAIN I would say: In second generation wireless networks, the handoff PROCESS is mobile controlled and is known as mobile ASSISTED handoff (MAHO). The mobile units in these networks perform several other functions not performed by first generation subscriber units.

The correct answer is (d) VLR, HLR

For explanation I would SAY: The visited system creates a VLR record for each NEW roamer and notifies the home system via IS-41 so it can update its own HLR. IS-41 allows the MSCS of neighboring SYSTEMS to automatically HANDLE the registration and location validation of roamers so that users no longer need to manually register as they travel.

Correct answer is (d) 53 bytes

To explain: ATM CELLS have a fixed LENGTH of 53 bytes. It consists of 48 bytes of data and 5 bytes of header INFORMATION. Fixed length packets result in simple IMPLEMENTATION of fast packet switches.

Right choice is (d) Inexpensive to install

For EXPLANATION: CDPD directly overlays with existing CELLULAR infrastructure and uses existing base station equipment, MAKING it simple and inexpensive to install. CDPD does not use the MSC, but rather has its own traffic ROUTING capabilities.

Correct ANSWER is (a) Radio PORT control unit

For explanation: In PACS/ WACS, the BSC is called a radio port control unit. This architectural change has allowed the data interface between the base STATION controller and the MSC to be standardized.

Right answer is (a) True

The explanation: Packet switching BREAKS each message into SMALLER units for transmission and recovery. When a message is broken into PACKETS, a certain AMOUNT of control information is added to each packet to provide source and destination identification, as well as error recovery PROVISIONS.

The correct option is (a) Cellular Digital Packet Data

To explain: US cellular standard CDPD stands for Cellular Digital Packet Data. In 1993, US cellular industry developed CDPD to COEXIST with the CONVENTIONAL VOICE only cellular system.

Correct choice is (a) Analog technology

Easy explanation: First GENERATION cellular and cordless TELEPHONE networks are based on analog technology. All first generation cellular systems USE FM modulation, and cordless telephones use a SINGLE base station to communicate with a single portable TERMINAL.

The correct choice is (a) Local access and TRANSPORT area

Easy explanation: In public switched telephone NETWORK, LATA stands for Local access and transport area. LATA is a city or a GEOGRAPHIC grouping of towns in PSTN.

The correct choice is (d) 400 SERVICES

The best I can explain: There are THREE MAIN types of services offered by the SS7 network. They are the Touchstar, 800 services, and alternate billing services.