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Torrent File
In the BitTorrent file distribution system, a torrent file or meta-info file is a computer file that contains metadata about files and folders to be distributed, and usually also a list of the network locations of trackers, which are computers that help participants in the system find each other and form efficient distribution groups called ''swarms''. Torrent files are normally named with the extension .torrent. A torrent file acts like a table of contents (index) that allows computers to find information through the use of a torrent client. With the help of a torrent file, one can download small parts of the original file from computers that have already downloaded it. These "peers" allow for downloading of the file in addition to, or in place of, the primary server. A torrent file does not contain the content to be distributed; it only contains information about those files, such as their names, folder structure, sizes, and cryptographic hash values for verifying file in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BitTorrent
BitTorrent is a Protocol (computing), communication protocol for peer-to-peer file sharing (P2P), which enables users to distribute data and electronic files over the Internet in a Decentralised system, decentralized manner. The protocol is developed and maintained by Rainberry, Inc., and was first released in 2001. To send or receive files, users use a Comparison of BitTorrent clients, BitTorrent client on their Internet-connected computer, which are available for a variety of computing platforms and Comparison of BitTorrent clients#Operating system support, operating systems, including BitTorrent (software), an official client. BitTorrent trackers provide a list of files available for transfer and allow the client to find peer users, known as "seeds", who may transfer the files. BitTorrent downloading is considered to be faster than HTTP ("direct downloading") and File Transfer Protocol, FTP due to the lack of a central server that could limit bandwidth. BitTorrent is one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BitTorrent Tracker
A BitTorrent tracker is a special type of server that assists in the communication between peers using the BitTorrent protocol. In peer-to-peer file sharing, a software client on an end-user PC requests a file, and portions of the requested file residing on peer machines are sent to the client, and then reassembled into a full copy of the requested file. The "tracker" server keeps track of where file copies reside on peer machines, which ones are available at time of the client request, and helps coordinate efficient transmission and reassembly of the copied file. Clients that have already begun downloading a file communicate with the tracker periodically to negotiate faster file transfer with new peers, and provide network performance statistics; however, after the initial peer-to-peer file download is started, peer-to-peer communication can continue without the connection to a tracker. Modern BitTorrent clients may implement a distributed hash table and the peer exchange ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bram Cohen
Bram Cohen is an American computer programmer, best known as the author of the peer-to-peer (P2P) BitTorrent protocol in 2001, as well as the first file sharing program to use the protocol, also known as BitTorrent. He is also the co-founder of CodeCon and organizer of the San Francisco Bay Area P2P-hackers meeting, was the co-author of Codeville and creator of the Chia cryptocurrency which implements the proof of space-time consensus algorithm. Early life and career Cohen grew up on the Upper West Side of Manhattan, New York City, as the son of a teacher and computer scientist. He claims he learned the BASIC programming language at the age of 5 on his family's Timex Sinclair computer. Cohen passed the American Invitational Mathematics Examination to qualify for the United States of America Mathematical Olympiad while he attended Stuyvesant High School in New York City. He graduated from Stuyvesant in 1993, and attended SUNY Buffalo. He later dropped out of college to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Extension
In computing, a plug-in (also spelled plugin) or add-in (also addin, add-on, or addon) is a software component that extends the functionality of an existing software system without requiring the system to be re-built. A plug-in feature is one way that a system can be customizable. Applications support plug-ins for a variety of reasons including: * Enable third-party developers to extend an application * Support easily adding new features * Reduce the size of an application by not loading unused features * Separate source code from an application because of incompatible software licenses Examples Examples of plug-in use for various categories of applications: * Digital audio workstations and audio editing software use audio plug-ins to generate, process or analyze sound. Ardour, Audacity, Cubase, FL Studio, Logic Pro X and Pro Tools are examples of such systems. * Email clients use plug-ins to decrypt and encrypt email. Pretty Good Privacy is an example of such plug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SHA-256
SHA-2 (Secure Hash Algorithm 2) is a set of cryptographic hash functions designed by the United States National Security Agency (NSA) and first published in 2001. They are built using the Merkle–Damgård construction, from a one-way compression function itself built using the Davies–Meyer structure from a specialized block cipher. SHA-2 includes significant changes from its predecessor, SHA-1. The SHA-2 family consists of six hash functions with digests (hash values) that are 224, 256, 384 or 512 bits: SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224, SHA-512/256. SHA-256 and SHA-512 are hash functions whose digests are eight 32-bit and 64-bit words, respectively. They use different shift amounts and additive constants, but their structures are otherwise virtually identical, differing only in the number of rounds. SHA-224 and SHA-384 are truncated versions of SHA-256 and SHA-512 respectively, computed with different initial values. SHA-512/224 and SHA-512/256 are also trunc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnet Links
Magnet is a URI scheme that defines the format of magnet links, a de facto standard for identifying files (URN) by their content, via cryptographic hash value rather than by their location. # Although magnet links can be used in a number of contexts, they are particularly useful in peer-to-peer file sharing networks because they allow resources to be referred to without the need for a continuously available host, and can be generated by anyone who already has the file, without the need for a central authority to issue them. This makes them popular for use as "guaranteed" search terms within the file sharing community where anyone can distribute a magnet link to ensure that the resource retrieved by that link is the one intended, regardless of how it is retrieved. History The standard for Magnet URIs was developed by Bitzi in 2002, partly as a "vendor- and project-neutral generalization" of the ed2k: and freenet: URI schemes used by eDonkey2000 and Freenet (now Hyphanet), re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UTF-8
UTF-8 is a character encoding standard used for electronic communication. Defined by the Unicode Standard, the name is derived from ''Unicode Transformation Format 8-bit''. Almost every webpage is transmitted as UTF-8. UTF-8 supports all 1,112,064 valid Unicode code points using a variable-width encoding of one to four one- byte (8-bit) code units. Code points with lower numerical values, which tend to occur more frequently, are encoded using fewer bytes. It was designed for backward compatibility with ASCII: the first 128 characters of Unicode, which correspond one-to-one with ASCII, are encoded using a single byte with the same binary value as ASCII, so that a UTF-8-encoded file using only those characters is identical to an ASCII file. Most software designed for any extended ASCII can read and write UTF-8, and this results in fewer internationalization issues than any alternative text encoding. UTF-8 is dominant for all countries/languages on the internet, with 99% global ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SHA-1
In cryptography, SHA-1 (Secure Hash Algorithm 1) is a hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecimal digits. It was designed by the United States National Security Agency, and is a U.S. Federal Information Processing Standard. The algorithm has been cryptographically broken but is still widely used. Since 2005, SHA-1 has not been considered secure against well-funded opponents; as of 2010 many organizations have recommended its replacement. NIST formally deprecated use of SHA-1 in 2011 and disallowed its use for digital signatures in 2013, and declared that it should be phased out by 2030. , chosen-prefix attacks against SHA-1 are practical. As such, it is recommended to remove SHA-1 from products as soon as possible and instead use SHA-2 or SHA-3. Replacing SHA-1 is urgent where it is used for digital signatures. All major web browser vendors ceased acceptance of SHA-1 SSL certifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hash List
In computer science, a hash list is typically a list of hashes of the data blocks in a file or set of files. Lists of hashes are used for many different purposes, such as fast table lookup (hash tables) and distributed databases (distributed hash tables). A hash list is an extension of the concept of hashing an item (for instance, a file). A hash list is a subtree of a Merkle tree. Root hash Often, an additional hash of the hash list itself (a ''top hash'', also called ''root hash'' or ''master hash'') is used. Before downloading a file on a p2p network, in most cases the top hash is acquired from a trusted source, for instance a friend or a web site that is known to have good recommendations of files to download. When the top hash is available, the hash list can be received from any non-trusted source, like any peer in the p2p network. Then the received hash list is checked against the trusted top hash, and if the hash list is damaged or fake, another hash list from another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexicographical Order
In mathematics, the lexicographic or lexicographical order (also known as lexical order, or dictionary order) is a generalization of the alphabetical order of the dictionaries to sequences of ordered symbols or, more generally, of elements of a totally ordered set. There are several variants and generalizations of the lexicographical ordering. One variant applies to sequences of different lengths by comparing the lengths of the sequences before considering their elements. Another variant, widely used in combinatorics, orders subsets of a given finite set by assigning a total order to the finite set, and converting subsets into increasing sequences, to which the lexicographical order is applied. A generalization defines an order on an ''n''-ary Cartesian product of partially ordered sets; this order is a total order if and only if all factors of the Cartesian product are totally ordered. Definition The words in a lexicon (the set of words used in some language) have a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Associative Array
In computer science, an associative array, key-value store, map, symbol table, or dictionary is an abstract data type that stores a collection of (key, value) pairs, such that each possible key appears at most once in the collection. In mathematical terms, an associative array is a function with ''finite'' domain. It supports 'lookup', 'remove', and 'insert' operations. The dictionary problem is the classic problem of designing efficient data structures that implement associative arrays. The two major solutions to the dictionary problem are hash tables and search trees..Dietzfelbinger, M., Karlin, A., Mehlhorn, K., Meyer auf der Heide, F., Rohnert, H., and Tarjan, R. E. 1994"Dynamic Perfect Hashing: Upper and Lower Bounds". SIAM J. Comput. 23, 4 (Aug. 1994), 738-761. http://portal.acm.org/citation.cfm?id=182370 It is sometimes also possible to solve the problem using directly addressed arrays, binary search trees, or other more specialized structures. Many programmin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
