Hi there!
This time, I will share with you about the application of VPN in GPON by VPLS.
What Is VPLS
Definition
The Virtual Private LAN Service (VPLS), also called the Transparent LAN Service (TLS) or virtual private switched network service, is a Layer 2 VPN (L2VPN) technology that is based on Multi-Protocol Label Switching (MPLS) and Ethernet technologies.
Purpose
The primary goal of VPLS is to interconnect multiple Ethernet LANs through the Packet Switched Network (PSN). In this manner, these LANs can function as one LAN. VPLS can implement the multipoint-to-multipoint VPN networking; therefore, by using the VPLS technology, service providers (SPs) can provide the Ethernet-based multipoint services through MPLS backbone networks. In addition, by utilizing the VPLS solution in which MPLS virtual circuits (VCs) function as the Ethernet bridge links, SPs can transparently transmit LAN services on the MPLS network.
VPLS PW Redundancy Applications
Application of VPLS Individual Access
The traffic of individual services such as high speed internet (HSI), voice over IP (VoIP) and broadband TV (BTV) are carried by the carrier's metropolitan area network (MAN).
The traditional bearing technologies such as the asynchronous transfer mode (ATM) and frame relay (FR) have some defects such as high cost for network construction, slow speed and complicated deployment. Moreover, the traditional bearing technologies only support the point-to-point (P2P) interconnection for users. With the development of IP technology, the Ethernet-based virtual private LAN service (VPLS) technology supports transparent transmission of the above-mentioned individual services and achieves the point-to-multipoint (P2MP) interconnection for users. In addition, the Ethernet-based VPLS has many advantages, such as low cost for network construction, high speed and simple deployment. Therefore, the VPLS technology is widely used in the current MAN to transmit the user traffic.
The HSI service is used as an example in the example network.
The MSAN/OLT is dual-homed to two AGS devices through the VPLS.
The user HSI access service is provided through the PPPoE dialup and maps to the VPLS domain through a VLAN in upstream direction.
PADI packets initiated from the user side are broadcast in the VPLS domain to which the packets belong. The broadcast packets are received on PE1 and PE2.
The delay response is used between PE devices to terminate the dialups of some users so that the load sharing can be achieved.
The split horizon between the VPLS and PW is enabled.
Application of VPLS Enterprise Access
With the business expansion, many enterprises establish branches in different areas and employees are often on business trips. Therefore, some applications (such as the VoIP, instant messages and network conference) are used widely in enterprises. These applications require a network that supports point-to-multipoint (P2MP) services. In addition, the network reliability must be ensured and a transparent and secure data channel is required for multi-point transmission because of the privacy of the enterprise business data. The VPLS technology is suitable to be deployed in this scenario.
The virtual private network (VPN) between different branches is achieved by deploying the VPLS.
The pseudo wire (PW) redundancy is used to protect the important branches (such as branch C in the figure).
An OLT/MSAN, functioning as the main node, implements the Layer 2 label switching, and other branches are connected to the VPLS network through backup PWs.
The split horizon between the VPLS and PW is canceled.
The basic Layer 2 forwarding mechanism in this scenario is consistent with that in the VPLS individual access scenario except that the split horizon needs to be canceled and the PW protection needs to be supported for Layer 2 forwarding in this scenario.
For the configuration process of VPLS, please click VPLS. If you can't open this link, please refer to this post to upgrade your permissions: How do we upgrade our account.
Thank you!
