Understanding Virtual Private LAN Service (VPLS)
Introduction to Virtual Private LAN Service (VPLS)
Virtual Private LAN Service (VPLS) is a type of Virtual Private Network (VPN) that provides a virtualized Ethernet environment. It allows organizations to extend their LANs across multiple sites, creating a single, large LAN across multiple physical locations. VPLS is similar to Multi-Protocol Label Switching (MPLS) VPNs, but there are some key differences between the two.
Differences between MPLS and VPLS
While both MPLS and VPLS provide a means to extend LANs over wide area networks (WANs), there are some key differences between the two. One of the main differences is that MPLS is a Layer 3 protocol, while VPLS is a Layer 2 protocol. This means that MPLS operates at the IP level, while VPLS operates at the data link level. As a result, MPLS is more suited for routing and traffic engineering, while VPLS is better suited for bridging and virtualizing Ethernet networks.
Another key difference between MPLS and VPLS is that MPLS requires a dedicated network infrastructure and specialized equipment, while VPLS can be implemented over any existing IP infrastructure. This makes VPLS more cost-effective, as it does not require additional hardware or software.
MPLS vs VPLS:
- MPLS is a Layer 3 Protocol while VPLS is a Layer 2 Protocol
- MPLS is suited for routing and traffic engineering while VPLS is suited for bridging and virtualizing Ethernet networks
- MPLS requires dedicated network infrastructure and specialized equipment while VPLS can be implemented over any existing IP infrastructure
- MPLS is more expensive
Implementations
VPLS is implemented by creating a virtual private network (VPN) that emulates a LAN over a wide area network (WAN). This is achieved by using Multi-Protocol Label Switching (MPLS) to create a Layer 2 VPN, which is then used to create a virtual Ethernet segment.
The main routing protocols used with VPLS are Border Gateway Protocol (BGP) and Label Distribution Protocol (LDP). BGP is used to distribute routing information between the various VPLS sites, while LDP is used to establish and maintain the label-switched paths (LSPs) that are used to carry the virtual Ethernet traffic. OSFP and IS-IS are also commonly used with VPLS and MPLS
Hardware Vendors Several hardware vendors provide VPLS solutions, including:
- Cisco
- Juniper Networks
- Nokia (previously Alcatel-Lucent)
- Huawei
- MikroTik
Conclusion VPLS is a cost-effective solution for organizations looking to extend their LANs across multiple sites. It is similar to MPLS VPNs, but operates at the data link level and can be implemented over existing IP infrastructure. Organizations can implement VPLS using a variety of routing protocols, including BGP and LDP, and hardware vendors such as Cisco, Juniper Networks, Nokia, Huawei and Mikrotik provide solutions that support VPLS.
