14 IT Networks and Electronic Commerce Flashcards
What is terminal emulation?
Remote connections to mainframes usually through personal computers rather than through dumb terminals.
What is distributed processing?
The decentralization of processing tasks and data storage and assigning these functions to multiple computers, often in separate locations.
What is a local area network (LAN)?
A LAN is any interconnection between devices in a single office or building.
What is a peer-to-peer network arrangement?
Very small networks with few devices, where every device is connected directly to every other. Peer-to-peer networks become increasingly difficult to administer with each added device.
What is the most cost-effective and easy-to-administer arrangement for LANs?
client-server model
How to client-server networks differ from peer-to-peer networks?
client-server networks differ from peer-to-peer networks in that the devices play more specialized roles. Client processes (initiated by the individual user) request services from server processes (maintained centrally).
What is a client-server network arrangement?
In a client-server arrangement, servers are centrally located and devoted to the functions that are needed by all network users. Ex - mail servers, application servers, file servers, internet servers, web servers
What is a client?
Any object that uses the resources of another object. Thus, a client can be either a device or software program. “Client” refers to a device that requests services from a server. This understanding of the term encompasses anyting from a powerful graphics workstation to a personal mobile device.
What is the key to the client-server model?
The key to the client-server model is that it runs processes on the platform most appropriate to that process while attempting to minimize traffic over the network. This is commonly referred to as the three-tiered architecture of client, application and database. Because of the specialized roles, client-server systems are often assembled with equipment from multiple vendors.
What are security risks that increased with the convenience and flexibility of decentralization?
- unauthorized software can be easily installed on the network from a desktop computer. This exposes the organization to both viruses and liability for copyright violation.
- important files stored on a local computer may not be backed up properly by the user
- applications written by users of local computers may not adhere to the standards of the organization, making data sharing difficult.
What is a wide area network (WAN)?
A wide area network (WAN) consists of a conglomerate of LANs over widely separated locations. The key aspect here is that a WAN can be either publicly or privately owned.
What is an advantage of a WAN?
The possibility of spreading the cost of ownership among multiple organizations.
What are examples of publicly owned WANs?
public telephone system and internet, available to any user with a compatible device. The assets of these networks are paid for by means other than individually imposed user fees.
What are public-switched networks?
Public-switched networks use public telephone lines to carry data. This arrangement is economical, but the quality of data transmission cannot be guaranteed and security is highly questionable.
What are privately owned WANs?
Privately owned WANs are profit-making enterprises. They offer fast, secure data communication services to organizations that do not wish to make their own large investments in the necessary infrastructure.
What are value-added networks (VANs)?
Value-added networks (VANs) are private networks that provide their customers with reliable, high-speed, secure transmission of data. To compete with the internet, these third-party networks add value by providing their customers with error detection and correction services, electronic mailbox facilities for electronic data interchange (EDI) purposes, EDI translation, and security for email and data transmissions.
What are virtual private networks (VPNs)?
Virtual private networks (VPNs) emerged as a relatively inexpensive way to solve the problem of the high cost of leased lines. A company connects each office or LAN to a local internet service provider and routes data through the shared, low-cost public internet. The success of VPNs depends on the development of secure encryption products that protect data while in transit.
What is an intranet?
A type of WAN, an intranet permits sharing of information throughout an organization by applying internet connectivity standards and web software (browsers) to the organization’s internal network. An intranet addresses the connectivity problems faced by organizations that have many types of computers. Its use is restricted to those within the organization.
What is an extranet?
A type of WAN, an extranet consists of the linked intranets of two or more organizations, for example, of a supplier and its customers. It typically uses the public internet as its transmission medium but requires a password for access.
