CHAPTER 1THE INDUSTRY

Public switched telephone network (PSTN)

Primary characteristicsanalog access, 300-3,400 Hz;circuit-switched duplex connection;switched bandwidth, 64 kbps, or 300-3,400 Hz for analog exchanges;immobility or, at best, very limited mobility; andmany function in common with another bearer network i.e. Narrowband Integrated Services Digital Network (N-ISDN).

In the 60sCertainly a physical networkDial telephonesFirst modems to be used for data transmission (300 or 600 bit/s)TelefaxThe access network was referred to as the local network. (copper wire)Attenuation problem (pulse code modulation (PCM) systems )

The 21st Century

PBX (Private Branch Exchange)It is a switch station for telephone systems.takes over the role of telephonistconnected to the group selector of the local exchange and not to its subscriber stage.

PBX Users of the PBX share a certain number of outside lines for making telephone calls external to the PBX Easier to call someone within a PBX because the number you need to dial is typically just 3 or 4 digits.

Dial up Modemconverted to analog signals (vice versa)Stand-alone modems complying with ITU-T Recommendation V.24.

contImportant teleservices provided by a PSTNfixed telephony;cordless telephony, or "fixed telephony with limited terminal mobility";fax (via a built-in modem); anddata communication (via modem).

Why broadband?Long connection set-up timeMust be disconnected for data transmission.The widespread installation of optical fiber and modem developments in coding and fault correction techniques

Faxdistributive service having only one recipient.Interest in broadcast and advertisingrequirements for short delays

Centrex

several local offices naturally wishes to be able to connect the different local PBXs (or centrex groups) with one another.

Compression and Modem Techniques To Support Video-Telephonylimited bandwidth of the network represents a bottleneck to the introduction of video and multimedia services into the PSTNlack of a videophone standard

Teleworkingcommonly used has been a telephone, a fax and a computer with a modemCan ordering or controlling other services via its keypad or via the use of voice recognition.can be utilised for high-speed modems

Cordless Telecommunications

replacing the cord between the telephone set and the handset by a radio connection.CT-0 (first generation) Capacity and interference problemsCT-1 did not provide sufficient mobility. CT-2 allowed private subscribers to use their terminals from a number of telepoints.CT-3 (digital cellular telephony) move freely within a limited area. Handling outgoing and incoming calls.European Digital Enhanced Cordless Telecommunications (DECT) and the Japanese Personal Handy-phone System (PHS).Two established standards exist today

DECTcan also be used for cordless access to N-ISDN and GSM.ability to reach several networks from a single terminal.specified interfaces to different networks, and interworking between them can be established through intelligent network (IN) functionality and signaling system No. 7 (SS7).

THE ROLES OF TELECOMMUNICATION MARKET PLAYERS

End-users - "the consumers" - are those utilising the telecommunications services.They may be Residential or Business Customer.Information service providers sell their information services to end-users.

contNetwork operators provide network services, such as PSTN, ISDN and Public Land Mobile Network (PLMN) services.act as intermediaries in the supply of information services and other value-added services to the end-users and bill for what they provide.Sometimes with specialised roles (access network operators or as transport network operators)

contContent providers produce the content of the services offered to end-users by the aforementioned service providers.Such as films, music or database information

BrokersService brokers combine services from a number of service providers and then offer complete service packages to end-users.Content brokers can support service providers in their selection of the contents to be included in their services, or they can support content providers in their attempts to market their products to service providers.

contCapacity brokers act as dealers in the distribution of capacity between the different network operators.Vendors of systems and equipment provide the systems - including the hardware and software - that are required for the implementation and control of the various services and networks.

STANDARDS-MAKING ORGANISATIONS

Official sanctioned

contAd-hoctask forces, user groups, interest groups, consortium,forum alliances, or institutes.

Authorities

to protect the safety of the citizens; to avoid technical barriers to trade in the form of different national requirements; and to encourage the development of technologies and markets.

Users

User interests in standardisation are as follows: it must be possible to use different makes together; products must be capable of being used worldwide; competition between two or more suppliers makes a product less expensive; and cooperation during the standardisation phase favours the choice of a good solution.

Suppliers

Suppliers' interest in standardisation: competition on equal terms; larger manufacturing volumes; new or larger markets; and more efficient research and development.

INTERNET SERVICE PROVIDER

the service provider gives you a software package, username, password and access phone number.ISPs themselves are connected to one another through Network Access Points (NAPs).ISP is also called Internet Access Provider (IAP), a company that provides access to theInternet.