L2 VPN

The Layer 2 VPN service is much like the Layer 2 point-to-point service, which makes it possible to reuse existing product blocks, with a few differences such as the absence of fixed inputs. The L2_vpn_virtual_circuit product block inherits from the L2_ptp_virtual_circuit product block, and adds attributes to (dis)allow VLAN retagging and control over the BUM filter. And because a VPN can have one or more endpoints, unlike a point-to-point that has exactly two endpoints, the list of service attach points is overridden to reflect this.

classDiagram
    direction TB
    namespace L2VPNProduct {
        class L2VPNVirtualCircuitBlock {
            inherits from L2VPNVirtualCircuit
            +bum_filter: boolean
            +vlan_retagging: boolean
            +sap: list[L2ServicAttachmentPointBlock]
        }
        class L2ServiceAttachmentPointBlock {
            +vlan_range: vlan_range_type
            +port: PortBlock
        }
    }
    namespace PortProduct {
        class PortBlock {
            +device: DeviceBlock
            +port_name: str
        }
    }

    L2VPNVirtualCircuitBlock "1" --> "2..n" L2ServiceAttachmentPointBlock
    L2ServiceAttachmentPointBlock "1" --> "n" PortBlock

• bum_filter: enable broadcast, unknown unicast, and multicast (BUM) traffic filter
• vlan_retagging: allow VLAN retagging on endpoints
• sap: a constrained list of at least one Layer2 service attach point