Çok protokollü etiket anahtarlama ve MPLS sanal özel network çözümleri

The aim of this thesis is; why we use MPLS and what advantages that it provides in Virtual Private Networks (VPNs). MPLS is an improved method for forwarding packets through a network using information contained in labels attached to IP packets. The labels are inserted between the Layer 3 header and the Layer 2 header in the case of frame-based Layer 2 technologies, and they are contained in the virtual path identifier (VPI) and virtual channel identifier (VCI) fields in the case of cell-based technologies such as ATM. MPLS combines Layer 2 switching technologies with Layer 3 routing technologies. The primary objective of MPLS is to create a flexible networking fabric that provides increased performance and stability. This includes traffic engineering and VPN capabilities, which offer quality of service (QoS) with multiple classes of service (CoS). MPLS also provides a flexible and elegant VPN solution based on the use of LSP tunnels to encapsulate VPN data. VPNs give considerable added value to the customer over and above a basic best effort IP service, so this represents a major revenue-generating opportunity for SPs.