Hi there!
This time, I will share with you about the application of VPN in GPON by BGP/MPLS IP VPN.
Basic BGP/MPLS IP VPN
A basic BGP/MPLS IP VPN is an L3VPN network that covers only one carrier's network, which is an MPLS backbone network that does not span multiple ASs, as shown in following figure. A basic BGP/MPLS IP VPN has the following characteristics:
Transmits packets using extended BGP.
Encapsulates and transmits VPN packets over MPLS LSPs serving as public network tunnels.
Allows a device that can play PE, P, and CE roles to play only one role at a time.
BGP/MPLS IP VPN offers the following benefits:
Enables users to communicate with each other over networks of geographically different regions.
Ensures the security of VPN user data during transmission over the public network.
Route Advertisement on a Basic BGP/MPLS IP VPN
On a basic BGP/MPLS IP VPN, CEs and PEs are responsible for advertising VPN routes, whereas Ps only need to maintain backbone network routes without knowing VPN routing information. Generally, a PE maintains the routes of VPNs that the PE accesses, rather than all VPN routes. VPN route advertisement consists of the following phases: Route advertisement from the local CE to the ingress PE Route advertisement from the ingress PE to the egress PE Route advertisement from the egress PE to the remote CE After the process of route advertisement is complete, the local and remote CEs can set up reachable routes, and VPN routing information can be advertised on the backbone network.
Packet Forwarding on a BGP/MPLS IP VPN
On a BGP/MPLS IP VPN backbone network, a P does not know VPN routing information. VPN packets are forwarded between PEs over tunnels. Following figure shows an example of packet forwarding on a BGP/MPLS IP VPN. A packet is transmitted from CE1 to CE2. I-L indicates an inner label, and O-L indicates an outer label. The outer label directs the packet to the BGP next hop, and the inner label identifies the outbound interface for the packet or the VPN to which the packet belongs.
The forwarding process is as follows:
1. CE1 sends a VPN packet to the ingress PE.
2. After receiving the packet from an interface bound to a VPN instance.
3. After receiving the packet, the egress PE removes the outer label of the packet.
4. The egress PE removes the inner label residing at the bottom of the label stack.
5. The egress PE sends the packet from the corresponding outbound interface to CE2. After its labels are removed, the packet becomes a pure IP packet.
The above contents are from the ma5800 product manual. For more details, please visit the BGP and MPLS IP VPN. If you can't open this link, please refer to this post to upgrade your permissions: How do we upgrade our account.
Thank you!
