Cisco Cisco Access Registrar 3.5 - Manual (Page 71)

Glossary
GL-5
Cisco Access Registrar 3.5 Concepts and Reference Guide
OL-2683-02
P
packet A block of data in a standard format for transmission.
PAP Password Authentication Protocol is a simple PPP authentication mechanism in which a cleartext
username and password are transmitted to prove identity.
Payload The contents of a request packet.
PDU Protocol Data Unit—An SNMP compliant request, response, or trap message.
PE Router Provider Edge router—a router located at the edge of the provider’s MPLS core network.
POP Point of Presence is the dial-in point or connection point for users connecting to an ISP.
PPD Packet Processing Delay is the amount of time required for each peer to process the maximum amount
of data buffered in their offered receive packet window. The PPD is the value exchanged between the
LAC and LNS when a call is established. For the LNS, this number should be small. For an LAC
supporting modem connections, this number could be significant.
PPP Point-to-Point Protocol—a multiprotocol and includes UDP, Frame Relay PVC, and X.25 VC.
Profile A collection of one or more attributes that describe how a user should be configured; for example, a
profile may contain an attribute whose value specifies the type of connection service to provide the
user, such as PPP, SLIP, or Telnet. Profiles can be set up for a specific user or can be shared amongst
users.
Provider Service Provider—A provider who operates the access networks and MPLS backbone and provides
MPLS VPN service on the backbone.
PSTN Public Switched Telephone Network enables async PPP through modems.
Q
Quality of Service
(QOS) A given Quality of Service level is sometimes required for a given user being tunneled between an
LNS-LAC pair. For this scenario, a unique L2TP tunnel is created (generally on top of a new SVC) and
encapsulated directly on top of the media providing the indicated QOS.
R
RAC Client The IOS DHCP client used to generate requests for host addresses and subnets for non-PPP clients.
RADIUS Remote Authentication Dial-In User Service. The RADIUS protocol provides a method that allows
multiple dial-in Network Access Server (NAS) devices to share a common authentication database.
RADIUS Client A Network Access Server (NAS) operates as a client of RADIUS. The client is responsible for passing
user information to designated RADIUS servers, and then acting on the response that is returned. A
RADIUS server can act as a proxy client to other RADIUS servers.