VPLS and MPLS: Spot the difference
Today we will discuss on the difference between the VPLS and MPLS technology, although both these techniques used for the connectivity of the customer sites across the globe. VPLS stands for Virtual Private LAN services and MPLS stands for Multi protocol labeled switching.
VPLS is a ethernet based multipoint connectivity over IP networks or it can be done over the MPLS networks. VPLS is one way of connecting the sites and can be point to point or point to multipoint or you can have multipoint to multipoint type of connectivity over the IP networks.
If you analysis the connectivity of the VPLS, it is ethernet based connectivity across the sites, so it means that it will give you the Layer 2 connectivity between the sites. All services in a VPLS appears to be in the same LAN segment.VPLS uses edge routers that can learn, bridge and replicate on a VPN basis. These routers are connected by a full mesh of tunnels, enabling any-to-any connectivity.
On the other hand, MPLS- Multi-Protocol Labeled switching is the technique ( It can be layer 2 or layer 3) to connect the sites across the globe. In the case of MPLS, routing at the edge ( WAN routing protocol used -Mainly BGP, to connect PE-CE router communication) and Switching or labelling is used in the core. So you mean the connectivity between PE-CE is via routing protocol ( in the case you are using layer 3 MPLS services ) and PE-PE we are using label switching inside core ( Layer 2 or Layer 3 MPLS connectivity ). In the case of Layer 2 MPLS services, the technology uses between PE-CE can be frame-Relay, ATM or any other layer 2 connectivity.
So the MPLS tag is between Layer 2 and Layer 3 in the OSI model. It is rightly said that MPLS is a technology and VPLS is a services which uses MPLS technology for the connectivity as a underlying service. MPLS uses traffic engineering and Quality of the service with high availability.
Let's put a short description on the difference
VPLS is a ethernet based multipoint connectivity over IP networks or it can be done over the MPLS networks. VPLS is one way of connecting the sites and can be point to point or point to multipoint or you can have multipoint to multipoint type of connectivity over the IP networks.
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| Fig 1.1- VPLS Basic Architecture |
If you analysis the connectivity of the VPLS, it is ethernet based connectivity across the sites, so it means that it will give you the Layer 2 connectivity between the sites. All services in a VPLS appears to be in the same LAN segment.VPLS uses edge routers that can learn, bridge and replicate on a VPN basis. These routers are connected by a full mesh of tunnels, enabling any-to-any connectivity.
On the other hand, MPLS- Multi-Protocol Labeled switching is the technique ( It can be layer 2 or layer 3) to connect the sites across the globe. In the case of MPLS, routing at the edge ( WAN routing protocol used -Mainly BGP, to connect PE-CE router communication) and Switching or labelling is used in the core. So you mean the connectivity between PE-CE is via routing protocol ( in the case you are using layer 3 MPLS services ) and PE-PE we are using label switching inside core ( Layer 2 or Layer 3 MPLS connectivity ). In the case of Layer 2 MPLS services, the technology uses between PE-CE can be frame-Relay, ATM or any other layer 2 connectivity.
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| Fig 1.2- MPLS Connectivity |
So the MPLS tag is between Layer 2 and Layer 3 in the OSI model. It is rightly said that MPLS is a technology and VPLS is a services which uses MPLS technology for the connectivity as a underlying service. MPLS uses traffic engineering and Quality of the service with high availability.
Let's put a short description on the difference
- MPLS is a technology while VPLS is a service on the top of IP network or MPLS.
- VPLS is a layer 2 connectivity between the sites while MPLS is a technology inside the service provider and the user connectivity can be Layer 3 or Layer 2 depends upon the requirement.
- VPLS uses ethernet interfaces for the connectivity between the sites while MPLS can be run with the any kind of interfaces
- With the use of MPLS you can have the traffic engineering and Quality of service, VPLS cant uses traffic engineering.
- VPLS is generally used in the industry where customer wants to have the layer 2 information passed over the IP networks while MPLS can be used on the both cases where Layer 2 or Layer 3 information can be passed over the MPLS network.
- VPLS can be point to point or Multipoint connectivity- VPLS tunnels while MPLS is fully meshed technology and can be used to share the information across the sites based on the customer requirement ( the use of RT in place to import and export the routes with the specific PE routers)
- VPLS uses IEEE 802.1q Ethernet Bridging techniques and MPLS Core will use a full mesh of PWs and “split-horizon”forwarding.
