Glossary - Page 57
Glossary (cont.)
PE
Provider Edge. The router that is on the provider's side of the customer-provider interface.
PKI
Public Key Infrastructure. The mechanisms used both to allow a recipient of a signed message
to trust the signature and to allow a sender to find the encryption key for a recipient.
PPP
Point-to-Point Protocol. A layer 2 (data Link) protocol that allows two peer devices to transport
packets over a single link.
PPTP
Point-to-Point Tunneling Protocol. Provides a means for tunneling IP traffic in layer 2.
PPVPN
Provider-Provisioned VPN. A VPN that is managed by a service provider, not the user of the
VPN.
Public Key
A method for creating two keys (also called a
key pair
) that can be used to
Cryptography
encrypt and decrypt messages. One of the two keys, the
public key
, is widely published, while
the other key, the
private key
is kept secret. When you want to encrypt a message for a
recipient, you use that recipient's public key. Only someone with the private key can decrypt the
message. When you want to digitally sign a message, you use your private key. Anyone with
your public key can then check the signature and verify that only you could have signed the
message.
QoS
Quality of Service. There are many meanings for this term, but they generally revolve around
guarantees of service levels for Internet connections. With respect to VPNs, QoS generally
means the amount of throughput and/or the number of simultaneous connections that can be
sustained over a connection that uses IPSec.
RAS
Remote Access Server. Used by ISPs to allow customers access to their networks.
RFC
Request For Comments. The primary mechanism used by the IETF to publish documents,
including standards.
RSA
Rivest-Shamir-Adelman. The name of a cryptographic key-exchange algorithm popular in many
security protocols. Also the name of the company which controls the US patent on the algorithm.
SA
Security Association. A relationship established between two or more entities to enable them to
protect data they exchange. The relationship is used to negotiate characteristics of protection
mechanisms, but does not include the mechanisms themselves. IPSec usage: A simplex (uni-
directional) logical connection created for security purposes and implemented with either AH or
ESP (but not both).
SCCRQ
Start-Control-Connection-Request.
Sent by the L2TP client to establish the control connection.
SCCRP
Start-Control-Connection-Reply. Sent by the L2TP server to reply to the Start-Control-
Connection-Request message.
SCCRN
Start-Control-Connection-Connected. Sent in reply to a Start-Control-Connection-Reply
message to indicate that the tunnel establishment was successful.
SoftPhone
The term SoftPhone refers to an IP extension, a dedicated LAN attached H323 compliant
device, or a software program running on a multi-media PC. An example of a H323 software
phone is MS-Netmeeting (3.x).
SSL
Secure Sockets Layer. A protocol for encryption and authentication of Internet connections. See
TLS.
TCP/IP
Transmission Control Protocol/Internet Protocol. A networking protocol that provides
communication across inter-connected networks, between computers with diverse hardware
architectures and various operating systems.
TLS
Transport Layer Security. The standardized version of SSL.
UDP
User Datagram Protocol. Part of the TCP/IP protocol suite. UDP provides for exchange of
datagrams with acknowledgements or guaranteed delivery. UDP is a transport layer protocol.
VPN
A private data network that makes use of the public telecommunication infrastructure,
maintaining privacy through the use of a tunneling protocol and security procedures.
VPNC
Virtual Private Network Consortium. The trade association for manufacturers and providers in
the VPN market.
IP Office (R3.0) Virtual Private Networking
Glossary - Page 57
40DHB0002UKER Issue 3 (4th February 2005)
Part 3 VoIP Configuration
