Ethernet MAC Chaining

This document introduces and describes a simple and highly scalable service function chaining mechanism called MAC chaining which is built largely on existing Ethernet frame and forwarding capabilities. MAC chaining uses IEEE 802 Media Access Control (MAC) addresses to provide flexible and complete service function chains. It is largely transparent to layers above Ethernet and designed to augment and coexist with existing virtual and physical network forwarding. MAC chaining is achievable in some devices and virtual switches today using existing protocols.