資料通訊系統的種類
資料通訊是通訊技術和計算機技術相結合而產生的一種新的通訊方式。接下來小編為大家整理資料通訊系統的種類，希望對你有幫助哦!
There are five basic types of data communication system:
Off-line data transmission is simply the use of a telephone or similar link to transmit data without involving a computer equipment used at both ends of such a link is not part of a computer, or at least does not immediately make the data available for computer process, that is, the data when sent and/or received are 'off-line'. This type of data communication is relatively cheap and simple.
Remote batch is the term used for the way in which data communication technology is used geographically to separate the input and /or output of data from the computer on which they are processed in batch mode.
On-line data collection is the method of using communications technology to provide input data to a computer as such input arises-the data are then stored in the computer(say on a magnetic disk)and processed either at predetermined intervals or as required.
Enquiry-response systems provide, as the term suggests, the facility for a user to extract information from a enquiry facility is passive, that is, does not modify the information interrogation may be simple, for example, 'RETRIEVE THE RECORD FOR EMPLOYEE NUMBER 1234' or systems may useterminals producing hard copy and /or visual displays.
Real-time systems are those in which information is made available to and processed by a computer system in a dynamic manner so that either the computer may cause action to be taken to influence events as they occur(for example as in a process control application)or human operators may be influenced by the accurate and up-to-date information stored in the computer, for example as in reservation systems.
有五種基本的資料通訊系統：
離線資料傳輸是簡單地利用電話或類似的鏈路來傳輸資料，不包括計算機系統。這樣一條鏈路兩端所使用的裝置不是計算機的部件，或至少不是立刻把資料提供給計算機處理，即資料在傳送或接收時是離線的。這種資料通訊相對來說比較便宜和簡單。
遠端批處理一詞適用於這樣一種方法：採用資料通訊技術來使資料的輸入和輸出在地理上遠離按批處理模式處理處理它們的計算機。
聯機資料收集指的是用資料通訊技術來向計算機即時提供剛產生的輸入資料這種方法。資料於是儲存在計算機裡(比如磁碟上)，並按預定時間間隔或者根據需要進行處理。
詢問——應答系統，顧名思義，是為使用者提供從計算機提取資訊的功能。詢問功能是被動的。也就是說，它不修改所儲存的資訊。提問可以很簡單，例如："檢索僱員號碼為1234的記錄"也可以是複雜的。這類系統可能要使用能產生硬拷貝和(或)可視顯示的終端。
實時系統是這樣一類系統，其中計算機系統是在動態情況下取得和處理資訊，以便可使計算機採取動作來影響正在發生的事件(比如在過程控制應用中)或者可通過儲存在計算機裡的準確且不斷更新的資訊來影響人(操作員)，比如在預售系統中。
