In Data Communication, The Objective Is To Get The Data

In data communication, the objective is to get the data to the right destination at the right time with minimum possible cost and minimum possible errors. The four main communication processors and the extent to which they support the achievement of the objectives are: Communication processors are processors with specific optimisations to support communication sys-tems. Communication processors exist in a wide variety of forms and can be categorized based on the communication system, such as wired or wireless and based on the layer in the communication system, such as the physical layer, the medium access control layer or the network layer. Communication processors can be further categorized based on the application, such as audio, video or data and the end system requiring the communication system such as a laptop, a cell phone or a personal computer 1. Modulation Demodulation (Modem). Signals consist of two components –the information signal and the carrier signal .The transmission of any signal over some communication medium usually involves modulation of a carrier. Prior to their transmission the information signal and the carrier signal are combined and the process of combining these two signals is called Modulation. 2. Concentrator As generally used, a concentrator is a device that acts as an efficient forwarder of data transmission signals. A remote access hub is sometimes referred to as a concentrator. The term aggregator is also frequently used with approximately the same meaning. A typical concentrator or remote access hub is a device that handles incoming dial-up calls for an Internet (or other network) point-of-presence and performs other services. A concentrator or hub may be able to handle up to 100 dial-up modem calls, support a certain number of ISDN connections, and support leased line and frame relay traffic while also functioning as a router 3. Multiplexers A multiplexer, sometimes referred to as a "multiplexor" or simply "mux", is a device that selects between a number of input signals. In its simplest form, a multiplexer will have two signal inputs, one control input, and one output. An everyday example of an analog multiplexer is the source selection control on a home stereo unit. Its a device that enables a single communication channel to carry data transmissions from multiple sources simultaneously .The device divides communication channel so that it can be shared by multiple transmission devices. 4. Front end processor Its a special purpose computer dedicated to communication management and is attached to the main/host computer ,it performs communication processing such as error control ,formatting ,editing,controlling,rooting,speed/signal conversion. A front end processor (FEP), or a communications processor, is a small-sized computer which interfaces to the host computer a number of networks, such as SNA, or a number of peripheral devices, such as terminals, disk units, printers and tape units. Data is transferred between the host computer and the front end processor using a high-speed parallel interface. The front end processor communicates with peripheral devices using slower serial interfaces, usually also through communication networks. The purpose is to off-load from the host computer the work of managing the peripheral devices, transmitting and receiving messages, packet assembly and disassembly, error detection, and error correction. [1] Two examples are the IBM 3705 Communications Controller and the Burroughs Data Communications Processor.

Question 2 Rationale behind the following a.

Optical Character recognition technology is used in processing utility bills.

b. Index sequential file organisation is used in record management Indexed File Organization Indexed files have records that contain, in addition to data and carriage-control information, one or more keys. Keys can be character strings, packed decimal numbers, and 16-bit, 32-bit, or 64-bit signed or unsigned integers. Every record has at least one key, the primary key, whose value in each record cannot be changed. Optionally, each record can have one or more alternate keys, whose key values can be changed. Unlike relative record numbers used in relative files, key values in indexed files are not necessarily unique. When you create a file, you can specify that a particular key have the same value in different records (these keys are called duplicate keys). Keys are defined for the entire file in terms of their position within a record and their length. In addition to maintaining its records, RMS builds and maintains indexes for each of the defined keys. As records are written to the file, their key values are inserted in order of ascending value in the appropriate indexes. This organization allows the following operations:

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Positioning the file at a particular record by direct access. In direct access reads, you use either a primary or alternate key, plus a specified key value, to locate the record. In direct access writes (given a record that contains key values in the predefined positions), RMS automatically adds the record to the file and adds the primary and alternate key values to the appropriate indexes. You can also access records sequentially, where the sequence is defined by the index for a specified key. Finally, you can access records directly by RFA; RMS returns the RFA in a parameter block whenever it writes a record, and you can access and use the RFA to locate the appropriate record. You can access any file organization with the RFA. Reading any record, including sequential reads controlled by a key's index. Deleting any record. Updating an alternate key's value, if the key's definition permits its value to change. Writing records selectively, based on the value of a key and, when allowed in the key's definition, based on duplicate values. If duplicate values are permitted, you can write records containing key values that are present in the key's index. If duplicate values are not permitted, such write operations are rejected.

c.

Online collaboration that is facilitated with the right collaborative tools and work environments will promote common knowledge among work teams and will lead them to accomplish common goals. Through this virtual collaboration, far-flung work teams can share files, text chat about a current problem, and use polling features over their intranet or the public Internet. In this special environment called a workspace, teams within the collaborative environment build community and unity among their teams. Today's collaborative tools are software applications that enable work

teams to collectively author and archive their work, to be notified for events on a group calendar, and to collaborate with vendors and partners on a secure web server. These collaborative tools can be hosted or non-hosted, and they can focus on real-time (conferencing and instant messaging) or asynchronous time (calendars, schedules, and forums). Many small to medium companies opt to have collaborative software vendors host their workspaces, while larger companies may want to install the collaborative intranet onto their own server. When these collaboration solutions are hosted, companies can dive right into a collaboration environment to improve their project and knowledge management processes immediately. Examples of collaborative software tools that offer both hosted and licensed solutions include eRoom.net and Facilitate.com. ERoom offers collaborative solutions for any sized business ERoom markets its collaboration tools to fit both small businesses and large enterprises. Small businesses would use its hosted solution and enterprises would use its enterprise content management (ECM) platform, Documentation 5, which integrates into a company's IT structure. Small business features –

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eRoom has collaborative tools like the ApplicationXtender that manages, stores and organizes critical project information while the eRoom workspace offers multi-layered threaded discussions, drop and drag file sharing, plus real time and scheduled change • information.

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eRoom helps enterprises in the banking, pharmaceutical, medical and architecture fields with their project management and client resources. Some of the Documentation 5 features include authoring information, so teams can create and maintain websites and content integration that disseminates information to team members and connects team members with queries with those who have the answers. The Facilitate 8.5 tool can improve your company's online meetings

Facilitate 8.5 is an online meeting and survey tool offered by Facilitate.com that a small to medium sized company can host or a larger enterprise can deploy onto their own server to enable quick decision-making. This tool can rapidly build consensus among members of an online team with collaborative tools that include online chat rooms, voting and prioritizing, action plans to keep track of a team's progress, brainstorm templates, surveying tools, and shared work agendas. Facilitate 8.5 is flexible enough to manage a small regional meeting to a large international conference. This online software solution also offers consulting services and additional training resources. Find the right web collaboration tool to meet your businesses' needs When team members collaborate on a major project over an online workspace, they need a reliable web collaboration tool that will help them meet their deadlines, allow all of their voices to be heard, and permit quick access to stored information. When selecting a collaboration tool, decision-makers need to locate a software application that would best fit that company's industry, size, and communication standards, so that up-front integration costs will result in long-term savings. Collaborative management tools Collaborative management tools facilitate and manage group activities. Examples include:

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electronic calendars (also called time management software) — schedule events and automatically notify and remind group members project management systems — schedule, track, and chart the steps in a project as it is being completed workflow systems — collaborative management of tasks and documents within a knowledge-based business process

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knowledge management systems — collect, organize, manage, and share various forms of information enterprise bookmarking — collaborative bookmarking engine to tag, organize, share, and search enterprise data prediction markets — let a group of people predict together the outcome of future events extranet systems (sometimes also known as 'project extranets') — collect, organize, manage and share information associated with the delivery of a project (eg: the construction of a building) social software systems — organize social relations of groups online spreadsheets — collaborate and share structured data and information

Electronic communication tools Electronic communication tools send messages, files, data, or documents between people and hence facilitate the sharing of information. Examples include:

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synchronous conferencing e-mail faxing voice mail Wikis Web publishing revision control