# Key distribution

﻿
Key distribution

In symmetric key cryptography, both parties must possess a secret key which they must exchange prior to using any encryption. Distribution of secret keys has been problematic until recently, because it involved face-to-face meeting, use of a trusted courier, or sending the key through an existing encryption channel. The first two are often impractical and always unsafe, while the third depends on the security of a previous key exchange.

In public key cryptography, the key distribution of public keys is done through public key servers. When a person creates a key-pair, he keeps one key private and the other, public-key, is uploaded to a server where it can be accessed by anyone to send the user a private, encrypted, message.

Secure Sockets Layer (SSL) uses Diffie-Hellman key exchange if the client does not have a public-private key pair and a published certificate in the Public Key Infrastructure, and Public Key Cryptography if the user does have both the keys and the credential.

In secret sharing a secret (password, key, trade secret,...) is used as a seed to generate a number of distinct secrets, and the pieces are distributed so that some subset of the recipients can jointly authenticate themselves and use the secret information without learning what it is. Secret sharing is also called secret splitting, key splitting, and split knowledge.

We want to share "N" secrets among "M" people so that any "M" < "N" of them ("M" of "N") can regenerate the original information, but no smaller group up to "M" − 1 can do so. There are mathematical problems of this type, such as the number of points needed to identify a polynomial of a certain degree (used in Shamir's scheme), or the number of intersecting hyperplanes needed to specify a point (used in Blakley's scheme). We can hand out data specifying any number of points on the curve, or hyperplanes through the point, without altering the number needed to solve the problem and, in our application, access the protected resource.

Key distribution is an important issue in wireless sensor network (WSN) design. There are many key distribution schemes in the literature that are designed to maintain an easy and at the same time secure communication among sensor nodes. The most accepted method of key distribution is WSNs is key predistribution, where secret keys are placed in sensor nodes before deployment. When the nodes are deployed over the target area, the secret keys are used to create the network. For more info see: key distribution in wireless sensor networks.

Wikimedia Foundation. 2010.

### Look at other dictionaries:

• Key distribution in wireless sensor networks — Key distribution is an important issue in WSN design. It is a newly developing field due to the recent improvements in wireless communications.Wireless sensor networks are networks of small, battery powered, memory constraint devices named sensor …   Wikipedia

• Key distribution center — In cryptography, a key distribution center (KDC) is part of a cryptosystem intended to reduce the risks inherent in exchanging keys. KDCs often operate in systems within which some users may have permission to use certain services at some times… …   Wikipedia

• Key Distribution Center — Ein Key Distribution Center (abgekürzt: KDC, engl. für Schlüssel Verwaltungs Zentrale, auch Trust Center genannt oder, im Kerberos System, Kerberos Server), gibt für angemeldete Nutzer in einem Netzwerk auf Anforderung eine Ausweis Datei (TGT)… …   Deutsch Wikipedia

• Key distribution centre — (CKD)   An ISO term. A facility which generates and returns cryptographic keys for distribution …   International financial encyclopaedia

• Quantum key distribution network — Quantum Key Distribution Networks are future networks that are capable to provide QKD in passive optical networks. These networks will be integrated within the nowadays classical networks with the minor impact in the optical infrastructures. The… …   Wikipedia

• Key authentication — is a problem that arises when using public key cryptography. It is the process of assuring that the public key of person A held by person B does in fact belong to person A .In traditional symmetric key cryptography, this problem wasn t an issue… …   Wikipedia

• Key (cryptography) — In cryptography, a key is a piece of information (a parameter) that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the… …   Wikipedia

• Distribution — Contents 1 In mathematics, science, and technology 1.1 In mathematics 1.2 In science …   Wikipedia

• Key Largo Woodrat — Conservation status Endangered ( …   Wikipedia

• Key largo (film) — Pour les articles homonymes, voir Key Largo. Key Largo est un film de 1948 avec Humphrey Bogart, Lauren Bacall, Edward G. Robinson et Claire Trevor. Il a été réalisé par John Huston. Claire Trevor a emporté pour ce film l Oscar 1949 de la… …   Wikipédia en Français