SnapGear 2.0.1 user manual Dns, Appendix B Terminology

Certificates	A digitally signed statement that contains information about an entity
	and the entity's public key, thus binding these two pieces of information
	together. A certificate is issued by a trusted organization (or entity)
	called a Certification Authority (CA) after the CA has verified that the
	entity is who it says it is.
Certificate	A Certificate Authority is a trusted third party, which certifies public
Authority	key's to truly belong to their claimed owners. It is a key part of any
	Public Key Infrastructure, since it allows users to trust that a given
	public key is the one they wish to use, either to send a private message
	to its owner or to verify the signature on a message sent by that owner.
Certificate	A list of certificates that have been revoked by the CA before they
Revocation List	expired. This may be necessary if the private key certificate has been
	compromised or if the holder of the certificate is to be denied the ability
	to establish a tunnel to the CyberGuard SG appliance.
Data Encryption	The Data Encryption Standard is a block cipher with 64-bit blocks and a
Standard (DES)	56-bit key.
Dead Peer	The method of detecting if the remote party has a stale set of keys and
Detection	if the tunnel requires rekeying. To interoperate with the CyberGuard
	SG appliance, it must conform to the draft draft-ietf-ipsec-dpd-00.txt
DHCP	Dynamic Host Configuration Protocol. A communications protocol that
	assigns IP addresses to computers when they are connected to the
	network.
Diffie-Hellman	The groups used as the basis of Diffie-Hellman key exchange in the
Group or Oakley	Oakley protocol, and in IKE.
Group
Diffie-Hellman	A protocol that allows two parties without any initial shared secret to
Key Exchange	create one in a manner immune to eavesdropping. Once they have
	done this, they can communicate privately by using that shared secret
	as a key for a block cipher or as the basis for key exchange.
Distinguished	A list of attributes that defines the description of the certificate. These
Name	attributes include: country, state, locality, organization, organizational
	unit and common name.
DNS	Domain Name System that allocates Internet domain names and
	translates them into IP addresses. A domain name is a meaningful and
	easy to remember name for an IP address.
DUN	Dial Up Networking.
Encapsulating	Encapsulated Security Payload is the IPSec protocol which provides
Security Payload	encryption and can also provide authentication service.
(ESP)
Encryption	The technique for converting a readable message (plaintext) into
	apparently random material (ciphertext) which cannot be read if
	intercepted. The proper decryption key is required to read the
	message.
Ethernet	A physical layer protocol based upon IEEE standards.

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Appendix B – Terminology