Overlay network
lastmod 2026-01-02created 2024-05-294 edits
An overlay network is a virtual computer network built on top of a physical network. Nodes in an overlay network can be connected by virtual or logical links, and each link passes through many physical links in the network but does not take the physical links into account. For example, a P2P network can be called an overlay network, because it considers only the connections between peers without considering the physical delivery network. Dial-up Internet is an overlay on top of the telephone network.
Types of overlay networks
- Virtual Extensible Local Area Network (VxLAN)
- Generic Routing Encapsulation (GRE)
- IP Security (IPsec)
- Multiprotocol Label Switching (MPLS)
- Ethernet Virtual Private Network (EVPN)
- Software-Defined WAN (SD-WAN)
- Software-Defined Access (SD-Access)
- Application Centric Infrastructure (ACI)
- Cisco Virtual Topology System (VTS)
- Nebula