MPLS VPNs are a popular way to provide secure and scalable connectivity across different network domains. They use the MPLS protocol to label packets and route them through tunnels based on predefined policies. But how do you choose the best MPLS VPN technique for your network? In this article, you will learn about the most common MPLS VPN techniques and their advantages and disadvantages.
Layer 2 VPNs are also known as virtual private wire service (VPWS) or point-to-point VPNs. They create a virtual circuit between two customer edge (CE) devices, using a provider edge (PE) device as an intermediary. The PE device encapsulates the customer packets with an MPLS label and forwards them to the destination PE device, which decapsulates them and delivers them to the destination CE device. Layer 2 VPNs preserve the original layer 2 headers and protocols of the customer packets, such as Ethernet, Frame Relay, or ATM. Layer 2 VPNs are suitable for scenarios where the customer wants to have full control over the routing and addressing of their network, or where they need to support legacy or proprietary protocols.
1. VPWS, or Layer 2 VPNs, set up a virtual circuit between customer edge (CE) devices via a provider edge (PE). Simplifying, it's like a dedicated highway for data traffic. ?? 2. PE devices tag customer packets with MPLS labels and route them to the destination PE. It's akin to express shipping for data, preserving the original layer 2 details. ?? 3. Businesses love this when they crave control over their network's ins and outs. Great for legacy systems or funky protocols that need a special touch. ??? 4. Layer 2 VPNs keep your data's VIP status intact, making them the go-to for a variety of network needs. No fuss, just solid connectivity. ??
? Utilizes IP routing to establish virtual private networks, allowing service providers to offer secure and isolated communication between different customer sites. ? Extends Layer 2 connectivity across a service provider network, enabling the transparent transfer of Ethernet frames between geographically dispersed customer sites. ? A type of L2VPN that creates a virtual LAN to connect multiple customer sites as if they are on the same LAN, facilitating seamless communication between dispersed locations. ? Optimizes the use of network resources by dynamically routing traffic based on predefined constraints, improving efficiency and performance in MPLS networks.
Layer 2 VPNs Called VPLS (virtual private LAN service) VPLS are used to route voice, videos and AMI traffic between substations and data center locations
Layer 3 VPNs are also known as virtual private network service (VPRN) or IP VPNs. They create a virtual network between multiple customer sites, using a PE device as a router. The PE device assigns a unique VPN identifier (VPN ID) and a route distinguisher (RD) to each customer network, and advertises the customer routes to other PE devices using a routing protocol, such as BGP. The PE device also attaches an MPLS label to each customer packet and forwards it to the appropriate PE device, based on the VPN ID and the destination IP address. Layer 3 VPNs use the original layer 3 headers and protocols of the customer packets, such as IP, TCP, or UDP. Layer 3 VPNs are suitable for scenarios where the customer wants to have a flexible and scalable network, or where they need to support IP-based applications and services.
Another variant of Layer 3 MPLS based VPN is - MPLS IPsec VPN. This is a secure way for different geographical subdivisions in an organization to connect. It combines the efficiency of MPLS with the strong security offerings of IPsec. This technique makes sure that all the data sent over the network is encrypted, keeping it safe from unauthorized access. This is the most opted technique by global organizations.
Layer 2.5 VPNs are also known as virtual private LAN service (VPLS) or multipoint VPNs. They create a virtual LAN between multiple customer sites, using a PE device as a bridge. The PE device learns the MAC addresses of the customer devices and associates them with an MPLS label. The PE device then forwards the customer packets to the destination PE device, based on the MPLS label and the destination MAC address. Layer 2.5 VPNs preserve the original layer 2 headers and protocols of the customer packets, such as Ethernet. Layer 2.5 VPNs are suitable for scenarios where the customer wants to have a seamless and transparent network, or where they need to support broadcast and multicast traffic.
Segment Routing VPNs are a newer type of MPLS VPNs that use segment routing (SR) to simplify the label stack and the network configuration. Segment routing is a technique that uses a list of segments, or instructions, to steer the packets through the network. Each segment can be a node, a link, or a service. Segment routing VPNs use a single label to identify the VPN and the destination, and a segment routing header to encode the path. Segment routing VPNs can support layer 2, layer 3, or layer 2.5 VPNs, depending on the type of segments used. Segment routing VPNs are suitable for scenarios where the network operator wants to have more control and flexibility over the traffic engineering and the service delivery.