VPN Acronyms and Glossary

ATM

Asynchronous Transfer Mode. A virtual circuit based transport technology; supports circuits with QoS and reserved bandwidth.

Client organisation

An organisation that is a client of the VPN services which are provided by your organisation

DWDM

Dense Wavelength-Division Multiplexing. A transmission technology which multiplexes multiple optical carrier signals on a single optical fibre by using multiple wavelengths (colours) of laser lights to carry different signals. A DWDM multiplexor can support 40, 80 or even more wavelength inside of a single fibre. For example, each wavelength can carry SDH signals which give a maximum of 320 Gbit/s of capacity for 80 wavelength DWDM multiplexors.

Frame Relay, FR

A virtual circuit transport technology; it supports circuits with reserved bandwidth.

GRE

A tunneling protocol designed to encapsulate arbitrary network layer packets inside other arbitrary network layer packets e.g. IP inside of IP. Does not provide encryption for encapsulated packets.

IPSec

IP Security. A technology which provides confidentiality of transferring data by using secure tunnels that encrypt and encapsulate original end user IP packets into other IP packets, which are used to transport packets through a public IP network

L2TP

A tunneling protocol designed to encapsulate data link frames e.g. PPP frames inside IP packets. Does not provide encryption for encapsulated frames.

MPLS

Multi Protocol Label Switching. A hybrid technology, combining the IP network routing protocols for network topology learning and virtual circuit technique for data forwarding.

Partner organisation

An organisation with which your organisation has partnering business relationships. Sites of a partner organisation could be added to your VPN  to benefit from its functionality (security, performance etc)

PPP

Point to Point Protocol. A data link layer protocol designed for point-to-point links such as access links or core links of Wide Area Networks (WANs).

QoS

Quality of Service. A technology that counters the effects of congestion and queues in packet-switched networks. QoS divides the network traffic into different classes and processes those classes in different ways depending on the characteristics of the traffic e.g. by prioritising delay-sensitive traffic from Voice and Video applications.

SDH

Synchronous Digital Hierarchy. A high speed transmission technology which uses optical fibres for establishing circuits (a.k.a. connections) with dedicated bandwidth between end nodes. The speed of SDH connection can range from 155 Mbit/s up to 40 Gbit/s.

SSL

Secure Socket Layer. A technology which provides confidentiality of the data to be transferred by encrypting the application data and encapsulating it into transport layer protocols like TCP or UDP.

Tunnel

A very broad term which generally means that a data path has been created through a network, by encapsulating the original packets into some other protocol packets. Two popular examples for tunnelling are:

• hiding original packets (secure tunnels);
• providing a way of transferring non-supported packets, which are encapsulated within the network protocol packets, e.g. IP multicast through IP unicast-only network.  

Virtual circuit, VC

A logical transport connection within a network that provides an explicit path between end nodes through predefined intermediate nodes of a network. VC represents a connection-oriented way for data transmission through a packet-switched network, which assumes a preliminary set up of a path before the data transmission starts. Another fundamental way for data transmission is a datagram transmission that does not require a preliminary path to be set up.

VC technique separates traffic from different users; this feature is exploited by some types of VPNs.

VPN

Virtual Private Network.  A service that reproduces (emulates) the properties of a truly private enterprise network using a shared public networking infrastructure.

FE

Further Education

HE

Higher Education

LEA

Local Education Authority

RBC

Regional Broadband Consortium. Each RBC is a consortium of LEAs established to procure cost-effective broadband connectivity for schools in England.

RN

Regional Network. High performance multi-service networks connecting JANET educational and research organisations within specific regions

RNO

Regional Network Operator. An organization which operates the RN

RSC

Regional Support Centre. Thirteen RSCs were set up by the JISC in June 2000 to assist in the connection of all FE colleges to JANET.