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Privacy In File Sharing Networks
Peer-to-peer file sharing (P2P) systems like Gnutella, KaZaA, and eDonkey/eMule, have become extremely popular in recent years, with the estimated user population in the millions. An academic research paper analyzed Gnutella and eMule protocols and found weaknesses in the protocol; many of the issues found in these networks are fundamental and probably common on other P2P networks. Users of file sharing networks, such as eMule and Gnutella, are subject to monitoring of their activity. Clients may be tracked by IP address, DNS name, software version they use, files they share, queries they initiate, and queries they answer to. Clients may also share their private files to the network without notice due to inappropriate settings. Much is known about the network structure, routing schemes, performance load and fault tolerance of P2P systems in general. It might be surprising, but the eMule protocol does not provide much privacy to the users, although it is a P2P protocol which is s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peer-to-peer File Sharing
Peer-to-peer file sharing is the distribution and sharing of digital media using peer-to-peer (P2P) networking technology. P2P file sharing allows users to access media files such as books, music, movies, and games using a P2P software program that searches for other connected computers on a P2P network to locate the desired content. The nodes (peers) of such networks are end-user computers and distribution servers (not required). The early days of file-sharing were done predominantly by client-server transfers from web pages, FTP and IRC before Napster popularised a windows application that allowed users to both upload and download with a freemium style service. Record companies and artists called for its shutdown and FBI raids followed. Napster had been incredibly popular at its peak, spurning a grass-roots movement following from the mixtape scene of the 80's and left a significant gap in music availability with its followers. After much discussion on forums and in chat-rooms, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hash Function
A hash function is any function that can be used to map data of arbitrary size to fixed-size values. The values returned by a hash function are called ''hash values'', ''hash codes'', ''digests'', or simply ''hashes''. The values are usually used to index a fixed-size table called a ''hash table''. Use of a hash function to index a hash table is called ''hashing'' or ''scatter storage addressing''. Hash functions and their associated hash tables are used in data storage and retrieval applications to access data in a small and nearly constant time per retrieval. They require an amount of storage space only fractionally greater than the total space required for the data or records themselves. Hashing is a computationally and storage space-efficient form of data access that avoids the non-constant access time of ordered and unordered lists and structured trees, and the often exponential storage requirements of direct access of state spaces of large or variable-length keys. Use of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
File Sharing
File sharing is the practice of distributing or providing access to digital media, such as computer programs, multimedia (audio, images and video), documents or electronic books. Common methods of storage, transmission and dispersion include removable media, centralized servers on computer networks, Internet-based hyperlinked documents, and the use of distributed peer-to-peer networking. File sharing technologies, such as BitTorrent, are integral to modern media piracy, as well as the sharing of scientific data and other free content. History Files were first exchanged on removable media. Computers were able to access remote files using filesystem mounting, bulletin board systems (1978), Usenet (1979), and FTP servers (1970's). Internet Relay Chat (1988) and Hotline (1997) enabled users to communicate remotely through chat and to exchange files. The mp3 encoding, which was standardized in 1991 and substantially reduced the size of audio files, grew to widespread use in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SourceForge
SourceForge is a web service that offers software consumers a centralized online location to control and manage open-source software projects and research business software. It provides source code repository hosting, bug tracking, mirroring of downloads for load balancing, a wiki for documentation, developer and user mailing lists, user-support forums, user-written reviews and ratings, a news bulletin, micro-blog for publishing project updates, and other features. SourceForge was one of the first to offer this service free of charge to open-source projects. Since 2012, the website has run on Apache Allura software. SourceForge offers free hosting and free access to tools for developers of free and open-source software. , the SourceForge repository claimed to host more than 502,000 projects and had more than 3.7 million registered users. Concept SourceForge is a web-based source code repository. It acts as a centralized location for free and open-source software pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torrent Poisoning
Torrent poisoning is intentionally sharing corrupt data or data with misleading file names using the BitTorrent protocol. This practice of uploading fake torrents is sometimes carried out by anti-infringement organisations as an attempt to prevent the peer-to-peer (P2P) sharing of copyrighted content, and to gather the IP addresses of downloaders.Cuevas, R. et al. (2010Is Content Publishing in BitTorrent Altruistic or Profit-Driven?. ''Proceedings of the 6th International Conference on emerging Networking EXperiments and Technologies (ACM CoNEXT 2010)''. Philadelphia, USA. 30 November - 3 December 2010. Methods of attack Decoy insertion Decoy insertion (or content pollution) is a method by which corrupted versions of a particular file are inserted into the network. This deters users from finding an uncorrupted version and also increases distribution of the corrupted file.Luo et al (2009)An Effective Early Warning Scheme against Pollution Dissemination for Bittorrent. In: ''Glo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitzi
Bitzi was a website, operating from 2001 to 2013, where volunteers shared reports about any kind of digital file, with identifying metadata, commentary, and other ratings. Information contributed and rated by volunteers was compiled into the ''Bitpedia'' data set and reference work, described by Bitzi as a "digital media encyclopedia". The Bitpedia was published through the Bitzi website and web services under an open content license ( Creative Commons Attribution - Share Alike 2.0). Bitzi's standards and services have been adopted by a number of popular peer-to-peer file sharing systems. Bitzi was sponsored by a metadata publishing company of the same name based in San Francisco. History Founded by Gordon Mohr with Mike Linksvayer the Bitzi service launched in 2001. The Bitzi website shut down on 31 December 2013. Technology At Bitzi, files are identified by applying a strong hash function to their contents, which gives a distinct "fingerprint" for each file. Bitzi calls ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gnutella2
Gnutella2, often referred to as G2, is a peer-to-peer protocol developed mainly by Michael Stokes and released in 2002. While inspired by the gnutella protocol, G2 shares little of its design with the exception of its connection handshake and download mechanics. G2 adopts an extensible binary packet format and an entirely new search algorithm. Furthermore, G2 has a related (but significantly different) network topology and an improved metadata system, which helps effectively to reduce fake files, such as viruses, on the network. History In November 2002, Michael Stokes announced the Gnutella2 protocol to the Gnutella Developers Forum. While some thought the goals stated for Gnutella2 are primarily to make a clean break with the gnutella 0.6 protocol and start over, so that some of gnutella's less clean parts would be done more elegantly and, in general, be impressive and desirable; other developers, primarily those of LimeWire and BearShare, thought it to be a "cheap pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mix Network
Mix networks are routing protocols that create hard-to-trace communications by using a chain of proxy servers known as ''mixes'' which take in messages from multiple senders, shuffle them, and send them back out in random order to the next destination (possibly another mix node). This breaks the link between the source of the request and the destination, making it harder for eavesdroppers to trace end-to-end communications. Furthermore, mixes only know the node that it immediately received the message from, and the immediate destination to send the shuffled messages to, making the network resistant to malicious mix nodes. Each message is encrypted to each proxy using public key cryptography; the resulting encryption is layered like a Russian doll (except that each "doll" is of the same size) with the message as the innermost layer. Each proxy server strips off its own layer of encryption to reveal where to send the message next. If all but one of the proxy servers are compromis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Encryption
In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can decipher a ciphertext back to plaintext and access the original information. Encryption does not itself prevent interference but denies the intelligible content to a would-be interceptor. For technical reasons, an encryption scheme usually uses a pseudo-random encryption key generated by an algorithm. It is possible to decrypt the message without possessing the key but, for a well-designed encryption scheme, considerable computational resources and skills are required. An authorized recipient can easily decrypt the message with the key provided by the originator to recipients but not to unauthorized users. Historically, various forms of encryption have been used to aid in cryptography. Early encryption techniques were often used in military ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SHA-1
In cryptography, SHA-1 (Secure Hash Algorithm 1) is a cryptographically broken but still widely used 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. 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 certificates in 2017. In February ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random
In common usage, randomness is the apparent or actual lack of pattern or predictability in events. A random sequence of events, symbols or steps often has no :wikt:order, order and does not follow an intelligible pattern or combination. Individual random events are, by definition, unpredictable, but if the probability distribution is known, the frequency of different outcomes over repeated events (or "trials") is predictable.Strictly speaking, the frequency of an outcome will converge almost surely to a predictable value as the number of trials becomes arbitrarily large. Non-convergence or convergence to a different value is possible, but has probability zero. For example, when throwing two dice, the outcome of any particular roll is unpredictable, but a sum of 7 will tend to occur twice as often as 4. In this view, randomness is not haphazardness; it is a measure of uncertainty of an outcome. Randomness applies to concepts of chance, probability, and information entropy. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
