Ethernet is growing in popularity across all levels of enterprise including industrial processes and applications. There are a variety of Industrial applications in which Ethernet ring topologies are preferable to the star topologies common in enterprise networks. Ring networks provide inherent single-point fault tolerance. Ring nodes that include embedded switch technology reduce the need for infrastructure switches and simplify network cabling. Device Level Ring (DLR) protocol provides a means for detecting, managing and recovering from faults in a ring-based network.
Implementation of DLR imposes certain requirements upon the supporting network infrastructure. DLR does not inherently exclude the use of devices which do not support the DLR protocol in a DLR-enabled network. It is expected that legacy devices and other considerations will frequently dictate the use of such devices in a DLR network. However, the use of these devices in a DLR network may significantly affect DLR operation and performance. This whitepaper is intended to provide an overview of DLR and to provide guidelines for implementing a DLR network comprised of DLR devices and devices which do not support the DLR protocol.
Whitepaper: Guidelines for Using Device Level Ring (DLR) with EtherNet/IP (Pub 316) and presentation from the 2017 Industry Conference & 18th Annual Meeting of Members
Jordon Woods, Innovasic