Overlay Network Segmentation

The Overlay Network Segmentation is a mechanism to partition the SD-WAN Software-Defined Wide Area Network. SD-WAN is an application for applying SDN technology to WAN connections that connect enterprise networks across disparate geographical locations. overlay topology into multiple network segments, so as to control the distribution of routes to specific branches and VPNCs based on the network segment. You can have different overlay network segments mapped to different VLANs Virtual Local Area Network. In computer networking, a single Layer 2 network may be partitioned to create multiple distinct broadcast domains, which are mutually isolated so that packets can only pass between them through one or more routers; such a domain is referred to as a Virtual Local Area Network, Virtual LAN, or VLAN.. You can have a maximum of 32 network segments. Each VLAN can be part of only one overlay network segment. If an overlay network segment is not configured for a VLAN, overlay considers it to be a part of the default global segment.

Each Branch Gateway may have VLANs that belong to different network segments. When Overlay Route Orchestrator advertises the VLAN subnet Subnet is the logical division of an IP network. routes to the SD-WAN Wide Area Network. WAN is a telecommunications network or computer network that extends over a large geographical distance. Overlay, it tags the routes with the corresponding network segment information (color or route-distinguisher tag). Overlay Route Orchestrator organizes the overlay routing table based on network segments and orchestrates the routes to the devices (Branch Gateways and VPNCs) based on the network segments subscribed to by each device. By default, all the routes belong to the default network segment and all the devices subscribe to the routes for that default segment.

For more information about SD-WAN orchestrator, see SD-WAN Orchestrator Overview.

Figure 1  Overlay Network Segmentation