Composition of CPE devices
CPE devices have the following external interfaces:
- One or more LAN interfaces. You can combine LAN interfaces to form a switch using Linux bridges. In this way, you can improve the speed of data transmission to network devices connected to the switch, optimize the use of network resources and prevent bottlenecks.
If one of the interfaces fails, traffic can be moved to another interface that remains operational. Aggregating interfaces into a single switch also makes it easier to scale your network because you can add new interfaces to the switch as needed.
- One or more WAN interfaces. These interfaces can be wired or wireless.
Each CPE device has an OpenFlow software switch (virtual switch, hereinafter also referred to as softswitch), which is managed by the SD-WAN Controller and, by default, has interfaces with the following numbers:
- 1 (ovs-mgmt) — provides internal network management and configuration of the CPE device through the SD-WAN managementTunnel transport service after connecting to the orchestrator and SD-WAN Controller.
- 2 (ovs-lan) — provides a connection to a Linux bridge.
- 4800–4803 — GENEVE interfaces created for each WAN interface of the SD-WAN. The first GENEVE interface has the number 4800. Other GENEVE interfaces are assigned consecutive numbers. For example, the second GENEVE interface is assigned the number 4801.
As the source IP address, you must assign the IP address of the corresponding WAN interface. As the destination interface, you must assign the GENEVE interface number.
After the CPE device receives the parameters of WAN interfaces, a separate routing table is created for each WAN interface.
The figure below shows the logic diagram of a CPE device.
Logic diagram of a CPE device