Automatic Overlay Network Deployment
After underlay routes are automatically orchestrated, any two devices on the campus network can communicate with each other at Layer 3. Then virtual networks (VNs) can be deployed on the campus network. With VXLAN technology, iMaster NCE-Campus can automatically deploy VNs using abstracted pooling models. In automatic VN deployment, iMaster NCE-Campus instantiates resource pools. An administrator can select access interface ranges and subnets from the fabric resource pool to create VNs, without the need to concern about the specific VN implementation. This greatly loosens the coupling between service requirements and network implementation, and improves network planning efficiency.
To create VNs, the administrator only needs to perform the following steps on iMaster NCE-Campus:
Creating a Fabric
First, the administrator needs to create a network with resources pooled, which called fabric in the CloudCampus Solution for network virtualization. In essence, a fabric is a pool of network resources, as shown in Figure 1-12. Then the fabric can be virtualized into VNs for different services. For example, the following resources can be pooled: VLANs and IP addresses required for VN access, VN, VNI, and BD resources required for VN construction, as well as egress resources required for communication between VNs and external networks. In addition, VNs are constructed based on VXLAN technology. Another purpose of creating a fabric is to configure the VXLAN control plane and forwarding plane. The control plane is mainly used to forward VXLAN protocol packets, which requires selection of BGP EVPN peers. The forwarding plane is mainly used to forward VXLAN data packets, which requires selection of border and edge nodes (VTEPs) for establishing VXLAN tunnels.
Creating VNs
After a fabric is created, the administrator can create VNs based on actual service requirements. Each VN is an independent service network. In practice, a VN is created for each independent department. For example, VNs can be separately created for the marketing, finance, and R&D departments of an enterprise. Automatic VN deployment is to instantiate resource pools. The administrator can select VLAN IDs, IP addresses, access interface range, and external egresses from the fabric resource pools to create VNs, as shown in Figure 1-13.
