Decentralized Peer-to-Peer (P2P) overlay networks are distributed systems in nature, without any hierarchical organization or centralized control. They are typically divided in two main classes: structured and unstructured [39].
Structured P2P overlay network have tightly controlled topologies and content is placed at specified locations to efficiently solve queries. Some well-known examples are Content Addressable Network (CAN) [44], Chord [15] and Pastry [45]. Such overlays use a Distributed Hash Table (DHT) as substrate, where data objects (or values) are placed deterministically at the peers whose identifiers correspond to the data object’s unique key. In DHT-based systems, node identifiers are uniform-randomly assigned to the peers from a large space of identifiers. Similarly, unique identifiers, chosen from the same identifier space and called keys, are computed from data objects by means of a hash function. Keys are then mapped by the overlay network protocol to a unique live peer in the overlay network. The structured P2P overlay network support scalable storage and retrieval of {key,value} pairs. Given a key, operations like put(key,value) and get(key) can be invoked respectively to store and retrieve the data object corresponding to the key, which involves routing requests to the peer corresponding to the key. However, they only supports exact matching and are strongly affected by peer churn [31].
A Content Addressable Network [44] is designed around the idea of a virtual d-dimensional Cartesian coordinate space (i.e. d-torus), which is divided among the peers and used for assigning IDs to data resources. Each peer knows its neighbors’ IDs and IP addresses. While receiving a query, each node sends the message to a neigh...
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...ique uses the fact that nodes sharing a great amount of files tend to stay in the network for a longer time, and therefore, with querying this small portion of nodes, success rate is increased and search traffic is decreased.
To reduce the number of probed hosts and consequently reduce the overall search load, it has been proposed to replicate data on several hosts [67]. The location and the number of replica vary in different replication strategies. Thampi et al mention in [41] that there are three main site selection policies. Owner replication in which the object is replicated on the requesting node and the number of replica increases proportional to popularity of the file. Random replication in which replications are distributed randomly and the path replication in which the requested file is copied on all nodes on the path between the requesting node and source.
* A powerful search engine where you can search on metadata such as media type, category, performer, product name and more. Search results are grouped together so the same file will only be displayed once.
Roger Dingledine, Nick Mathewson, Paul Syverson. Tor: The Second-Generation Onion Router. Washington DC: Naval Research Lab, 2004.
The peer to peer lending activity consists for individuals to lend and borrow money to and from other inviduals against interests through a peer to peer fund. Peer to peer lending and borrowing is actually competitive.As with all financial market, the risk determines the spread between borrowing and lending rates. The return for the lender is higher than from a bank while the borrower obtains money for as low as 3 to 5%. Although, it may go as high as 20% to cover the risk.
...ing developers and businesses an easier way of distributing content to end users while sustaining low latency, high speed of data transfer, and no commitments.
Network Address Translation (NAT) is a standard used to allow multiple PCs on a private network to share a single, globally routable IPv4 address. NAT enables a user to have a large set of addresses internally and usually one address externally. The main reason NAT is often deployed is because IPv4 addresses are getting scarce. NAT is an immediate, but temporary, solution to the IPv4 address exhaustion problem that will eventually be rendered unnecessary with the deployment of the IPv6. The Internet Engineering Task Force has been aware of the impending depletion of the current address space for almost a decade.
Peer-to-peer is a communications model in which each party has the same capabilities and either party can initiate a communication session. Other models with which it might be contrasted include the client/server model and the master/slave model. In some cases, peer-to-peer communications is implemented by giving each communication node both server and client capabilities. In recent usage, peer-to-peer has come to describe applications in which users can use the Internet to exchange files with each other directly or through a mediating server.
A peer-to-peer network is relatively less expensive and much simpler to manage and setup, than client/server because money does not have to be invested in establishing server hardware or software and the number of users are minimal. Since, a peer-to-peer network is only preferable on networks operating on at least five to ten computers that do not need heavy file or application sharing, the cost is reasonable. On another note, based on a network with fifteen workstations, using a peer-to-peer configuration may save money upfront, but it could cost a business a lot of time and money in the long run. The reasons for this include, the lack of a central organization, which make data harder to find, no central storage location for archiving files, which may degrade client workstation performance, and lack of overall network management.
The first online peer to peer file-sharing application was Napster. Napster allowed people to copy music from their CDs onto their computers in mp3 format. They then allowed other members of Napster to download these songs onto their computers. Once this caught on, millions of people were downloading thousands of songs a day. And as you can imagine, this did not make the record companies happy with the idea that people were getting their music for free instead of buying the CD. It also caused a problem with some of the recording artists. Most notably Metallica.
4. A. Crespo and H. Garcia-Molina. Routing indices for peer-to-peer systems. In Proc. of the 28th International Conference on Distributed Computing Systems, July 2002.
The TCP/IP is the most important internet operation protocol in the world. While IP protocol performs the mass of the functions which is needed for the internet to work. It does not have many capabilities which are essential and needed by applications. In TCP/IP model these tasks are performed by a pair of protocols that operate at the transport layer. The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP). These two protocols are vital when it comes to delivering and managing the communication of numerous applications. To pass on data streams to the proper applications the Transport layer must identify the target application. First, to be able to attain this, Transport layer assigns an application an identifier. In the TCP/IP model call this identifier a port number. Every individual software process needing to access the network is assigned a un...
It simplifies the storage and processing of large amounts of data, eases the deployment and operation of large-scale global products and services, and automates much of the administration of large-scale clusters of computers.
Each host on P2P network works on special security daemon and Indra daemon.the P2P network requires reliability and trusted network.A,B & C are three hosts in P2P network. Attackers find weak access point on B.Attacking starts at host B, which is connected to C.At host C, intrusion detection system det...
With the popularity of the Internet, sales for CDs, DVDs, Movies, and many other products have increased. Along with the increase of sales has brought forth an ever increasing problem of illegal media being downloaded. Programs such as Bittorent, Kazaa, and other direct-connect networking programs have allowed the transferring of such illegal media. Downloading song files from the Internet over a free peer to peer network is the moral equivalent of shoplifting music CDs from the local mall.
All around the world people connected to the internet are downloading free digital content through P2P file sharing software.
So you believe Al Gore created the Internet? Well that’s not possible, because I did. Yes, it’s true, a few years ago I was sitting in my basement with nothing to do and suddenly the idea came to me: why not create an inter-connected network of networks that will allow users to send mail instantly, download copyrighted songs, and order pizza, all from the comfort of their own living room? OK, so maybe I didn’t exactly invent the Internet, but neither did Al Gore.