User`s manual

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DWS-1008 User’s Manual
D-Link Systems, Inc.
Appendix D - Glossary
Per-VLAN Spanning Tree protocol
See PVST+.
PIM
Protocol Independent Multicast protocol. A protocol-independent multicast routing protocol
that supports thousands of groups, a variety of multicast applications, and existing Layer 2
subnetwork technologies. PIM can be operated in two modes: dense and sparse. In PIM
dense mode (PIM-DM), packets are ooded on all outgoing interfaces to many receivers.
PIM sparse mode (PIM-SM) limits data distribution to a minimal number of widely distributed
routers. PIM-SM packets are sent only if they are explicitly requested at a rendezvous point
(RP).
PKCS
Public-Key Cryptography Standards. A group of specications produced by RSA Laboratories
and secure systems developers, and rst published in 1991. Among many other features and
functions, the standards dene syntax for digital certicates, certicate signing requests, and
key transportation.
PKI
Public-key infrastructure. Software that enables users of an insecure public network such
as the Internet to exchange information securely and privately. The PKI uses public-key
cryptography (also known as asymmetric cryptography) to authenticate the message sender
and encrypt the message by means of a pair of cryptographic keys, one public and one
private. A trusted certicate authority (CA) creates both keys simultaneously with the same
algorithm. A registration authority (RA) must verify the certicate authority before a digital
certicate is issued to a requestor.
The PKI uses the digital certicate to identify an individual or an organization. The private key
is given only to the requesting party and is never shared, and the public key is made publicly
available (as part of the digital certicate) in a directory that all parties can access. You use the
private key to decrypt text that has been encrypted with your public key by someone else. The
certicates are stored (and, when necessary, revoked) by directory services and managed by
a certicate management system. See also certificate authority (CA); registration authority
(RA).
plenum
A compartment or chamber to which one or more air ducts are connected.
plenum-rated cable
A type of cable approved by an independent test laboratory for installation in ducts, plenums,
and other air-handling spaces.
PMK
Pairwise master key. A code derived from a master secret and used as an encryption key
for IEEE 802.11 encryption algorithms. A PMK is also used to derive a pairwise transient key
(PTK) for IEEE 802.11i robust security. See also master secret; PTK.