Multi Protocol Label Switching Introduction

Multi Protocol Label Switching (MPLS) is a mechanism that when added to a routed IP network allows packets to be switched in hardware at high speed. It is considered a Layer 2 technology, although in many circles it is referred to as Layer 2 and a half as it mainly functions between the Data-Link Layer and the Network Layer of the OSI Reference Model.

A number of vendors had similar but proprietary technologies that became the basis for MPLS, for instance Cisco had Tag Switching and IBM had similar technology known as ARIS (Aggregate Route Based IP Switching). In 1997 a working group was formed under the guidance of the IETF (Internet Engineering Task Force), and eventually the name MPLS was decided upon.

An MPLS label is a short 32 bit identifier which is used to switch packets within an MPLS domain. When used with ATM (Asynchronous Transfer Mode) the label replaces the VPI/VCI, and a similar situation occurs when MPLS is used with some other Data-Link Layer technologies such as X.25 and Frame Relay. When Multi Protocol Label Switching is used with Ethernet, PPP, FDDI or Token Ring, the 32-bit Label is inserted between the Data-Link Layer and Network Layer headers. A label used in this manner is often referred to as a 'Shim Label'. Labels are normally changed switch by switch as the packet traverses the LSD (Label Switched Domain), and this is where the term Label Swapping comes from.

The original concept of MPLS was to combine the intelligence of Layer 3 Routing with the speed of Layer 2 Switching in order to provide a high throughput of Layer 3 packets. The technology is maturing and packet flows with the same FEC (Forward Equivalence Class) can be switched across certain paths to afford that packet flow the appropriate Quality of Service.

Some Information About VPN

VPN

VPN (Virtual Private Network) is a private network which is working on existing public infrastructure by creating a tunnel secured by different tunneling protocols. To subscribe to VPN subscription, the user's system need to connect to a remote VPN server which is based in another country. All information is encrypted because of the secured tunnel before it is routed through the tunnel. Moreover, Its requires authentication which has secured by using different VPN protocols namely L2TP and IPSec.

This technology allows hide IP. Nobody can identify your IP as well as your geographical position cannot be found. In addition, all Internet traffic to the VPN server will be encrypted with the key sustainable, and to understand what sites you have visited, it will be impossible.

If we need to acquire a secure channel between our home computer and the Internet without the ISP then thanks to the VPN server that ISP cannot be monitor your stay online and your visited internet pages. ISP logs will only write about the connectivity to the server.

If you are in the particular place, and access to the certain site is closed for IP addresses from your country.

Types of VPN

Now, we will elaborate on various kinds of VPN along with their characteristics so that it would easy for us to select which kind of VPN meets our requirements holistically.

L2TP VPN:

L2TP is an abbreviation of Layer 2 Tunneling Protocol. It provides no encryption by its own however, in its place uses the encryption of the protocol. Being an OSI Session Layer protocol, it is used as a layer 2 Tunnel. It uses Cisco's Layer 2 Forwarding (L2F) and also uses numerous types of Point-to-Point Tunneling Protocol (PPTP) VPN.