Download

When download is called in the electronic data processing, the receiving data on your own computer, the client, the. Across a network, usually the Internet, originate from a server The information transmitted or made ​​available for transfer data itself is referred to as a download. The download or the download is the counterpart to upload or the upload.

• 4.1 bandwidth

Basic principles

The basic principle of the download is to request and receive that one or more files from the provider.

In contrast, the basic principle of the upload is to send one or more files from the provider until they are received by the remote peer.

Technical Basics

Transmission protocols

The File Transfer Protocol (FTP) is an Internet protocol for downloading and uploading files, as well as a number of special applications. However, when data is downloaded from a website, FTP suspended at the desired location by the user to ask. After the confirmation of the storage place, the transfer is continued.

The HTTPS protocol is used for encryption and authentication of downloaded or uploaded data between the server and the client. The authentication is used, that can make sure each side of the identity of the communication partner and there is a secure data transmission.

Verification

The verification of the integrity of the downloaded file can be done via hash values ​​. Provided by a downloades MD5 checksums are created that are provided, for example, as separate files. After the transfer is complete the error-free transmission is verified by the recipient of the transferred file with a special program creates the MD5 checksum and compares it to the provider. If the two sums match, the data transmission with an extremely high probability is complete. However, the downloaded file may be infected still faulty or with malware and viruses.

Definitions

The term download ( download) is often interpreted broadly to the effect that received data are stored permanently, or at least will be saved temporarily.

In contrast, the term downloading is however taken from the related concept of streaming, which means the received data can be used immediately, while the transfer is not yet complete. If now the general definition of the term downloading true, it would mean that the data is only usable when it has been received in its entirety.

In this connection, download means specifically " receive and save " instead of simply " receive ".

An important criterion of distinction is the data transmission by e -mail. When sending data via e -mail this information will only be shipped as an appendix (Appendix ). It involves no download in the specific sense.

Limitations

Bandwidth

A download is always dependent on the available data transfer rate between the server and client. This has on the one hand an absolute limit on the physical limits of the respective transmission format or in the specifications of the devices. On the other hand, it is more relevant in the use of the internet that the provider or between client and server, in most cases, the data transfer rate throttling intentionally to ensure consistent treatment of clients.