文件銷毀中心 相關
廣告
搜尋結果
List of file signatures. This is a list of file signatures, data used to identify or verify the content of a file. Such signatures are also known as magic numbers or Magic Bytes. Many file formats are not intended to be read as text. If such a file is accidentally viewed as a text file, its contents will be unintelligible.
It opened on April 4, 1973, and was destroyed during the September 11 attacks in 2001. At the time of their completion, the Twin Towers —the original 1 World Trade Center (the North Tower) at 1,368 feet (417 m), and 2 World Trade Center (the South Tower) at 1,362 feet (415.1 m)—were the tallest buildings in the world.
- History of FTP Servers
- Protocol Overview
- Login
- Differences from Http
- Software Support
- Security
- Derivatives
- FTP Reply Codes
- Further Reading
- External Links
The original specification for the File Transfer Protocol was written by Abhay Bhushan and published as RFC 114 on 16 April 1971. Until 1980, FTP ran on NCP, the predecessor of TCP/IP. The protocol was later replaced by a TCP/IP version, RFC 765 (June 1980) and RFC 959 (October 1985), the current specification. Several proposed standards amend RFC ...
Communication and data transfer
FTP may run in active or passive mode, which determines how the data connection is established.(This sense of "mode" is different from that of the MODE command in the FTP protocol.) 1. In active mode, the client starts listening for incoming data connections from the server on port M. It sends the FTP command PORTM to inform the server on which port it is listening. The server then initiates a data channel to the client from its port 20, the FTP server data port. 2. In situations where the cl...
NAT and firewall traversal
FTP normally transfers data by having the server connect back to the client, after the PORT command is sent by the client. This is problematic for both NATs and firewalls, which do not allow connections from the Internet towards internal hosts.For NATs, an additional complication is that the representation of the IP addresses and port number in the PORT command refer to the internal host's IP address and port, rather than the public IP address and port of the NAT. There are two approaches to...
Data types
While transferring data over the network, five data types are defined: 1. ASCII (TYPE A): Used for text. Data is converted, if needed, from the sending host's character representation to "8-bit ASCII" before transmission, and (again, if necessary) to the receiving host's character representation, including newlines. As a consequence, this mode is inappropriate for files that contain data other than ASCII. 2. Image (TYPE I, commonly called Binary mode): The sending machine sends each file byte...
FTP login uses normal username and password scheme for granting access. The username is sent to the server using the USER command, and the password is sent using the PASS command. This sequence is unencrypted "on the wire", so may be vulnerable to a network sniffing attack. If the information provided by the client is accepted by the server, the se...
HTTPessentially fixes the bugs in FTP that made it inconvenient to use for many small ephemeral transfers as are typical in web pages. FTP has a stateful control connection which maintains a current working directory and other flags, and each transfer requires a secondary connection through which the data are transferred. In "passive" mode this sec...
File managers
Many file managers tend to have FTP access implemented, such as File Explorer (formerly Windows Explorer) on Microsoft Windows. This client is only recommended for small file transfers from a server, due to limitations compared to dedicated client software. It does not support SFTP. Both the native file managers for KDE on Linux (Dolphin and Konqueror) support FTP as well as SFTP. On Android, the My Files file manager on Samsung Galaxy has a built-in FTP and SFTPclient.
Web browser
For a long time, most common web browsers were able to retrieve files hosted on FTP servers, although not all of them had support for protocol extensions such as FTPS. When an FTP—rather than an HTTP—URLis supplied, the accessible contents on the remote server are presented in a manner that is similar to that used for other web content. Google Chrome removed FTP support entirely in Chrome 88, also affecting other Chromium-based browsers such as Microsoft Edge.Firefox 88 disabled FTP support b...
Download manager
Most common download managers can receive files hosted on FTP servers, while some of them also give the interface to retrieve the files hosted on FTP servers. DownloadStudioallows not only download a file from FTP server but also view the list of files on a FTP server.
FTP was not designed to be a secure protocol, and has many security weaknesses. In May 1999, the authors of RFC 2577listed a vulnerability to the following problems: 1. Brute-force attack 2. FTP bounce attack 3. Packet capture 4. Port stealing (guessing the next open port and usurping a legitimate connection) 5. Spoofing attack 6. Username enumerat...
FTPS
Explicit FTPS is an extension to the FTP standard that allows clients to request FTP sessions to be encrypted. This is done by sending the "AUTH TLS" command. The server has the option of allowing or denying connections that do not request TLS. This protocol extension is defined in RFC 4217. Implicit FTPS is an outdated standard for FTP that required the use of a SSL or TLS connection. It was specified to use different ports than plain FTP.
SSH File Transfer Protocol
The SSH file transfer protocol (chronologically the second of the two protocols abbreviated SFTP) transfers files and has a similar command set for users, but uses the Secure Shellprotocol (SSH) to transfer files. Unlike FTP, it encrypts both commands and data, preventing passwords and sensitive information from being transmitted openly over the network. It cannot interoperate with FTP software, though some FTP client software offers support for the SSH file transfer protocol as well.
Trivial File Transfer Protocol
Trivial File Transfer Protocol (TFTP) is a simple, lock-step FTP that allows a client to get a file from or put a file onto a remote host. One of its primary uses is in the early stages of booting from a local area network, because TFTP is very simple to implement. TFTP lacks security and most of the advanced features offered by more robust file transfer protocols such as File Transfer Protocol. TFTP was first standardized in 1981 and the current specification for the protocol can be found in...
Below is a summary of FTP reply codes that may be returned by an FTP server. These codes have been standardized in RFC 959by the IETF. The reply code is a three-digit value. The first digit is used to indicate one of three possible outcomes — success, failure, or to indicate an error or incomplete reply: 1. 2yz – Success reply 2. 4yz or 5yz – Failu...
RFC 697– CWD Command of FTP. July 1975.RFC 959– (Standard) File Transfer Protocol (FTP). J. Postel, J. Reynolds. October 1985.RFC 1579– (Informational) Firewall-Friendly FTP. February 1994.RFC 1635– (Informational) How to Use Anonymous FTP. May 1994.Anonymous FTP Servers by Country Code TLD (2012): "Offbeat Internet - Public Access - FTP". www.jumpjet.info. 2012. Archived from the original on 28 March 2023. Retrieved 16 January 2020.Wikipedia is written by volunteer editors and hosted by the Wikimedia Foundation, a non-profit organization that also hosts a range of other volunteer projects : Commons. Free media repository. MediaWiki. Wiki software development. Meta-Wiki. Wikimedia project coordination. Wikibooks. Free textbooks and manuals.
c. 6,000–25,000 [d] The World Trade Center in New York City collapsed on September 11, 2001, as result of the al-Qaeda attacks. Two commercial airliners hijacked by al-Qaeda terrorists were deliberately flown into the Twin Towers of the complex, resulting in a total progressive collapse that killed almost 3,000 people.
The National Security Agency (NSA) is an intelligence agency of the United States Department of Defense, under the authority of the Director of National Intelligence (DNI). The NSA is responsible for global monitoring, collection, and processing of information and data for foreign and domestic intelligence and counterintelligence purposes ...
The history of Windows dates back to 1981 when Microsoft started work on a program called "Interface Manager". It was announced in November 1983 (after the Apple Lisa, but before the Macintosh) under the name "Windows", but Windows 1.0 was not released until November 1985. [16]
