This presentation will take a historical view of how telecom and data center architectures evolved and argue that, as we architect CORD, the design must include a resilient management plane that can reach the edge even in the presence of infrastructure disruptions.Outline:- The PSTN was originally designed with control/management and payload (voice) sharing the same wires (in-band pulse dialing, in-band tone dialing, manual switching)
- In the 1970’s, the PSTN was modernized and control/management were decoupled from voice circuits (SS7 out-of-band signaling, TDM circuits, automated switching)
- In the 1990’s, I was part of the team designing the data center management infrastructure (working as a technology/product supplier to Yahoo! and other Internet pioneers). We borrowed the term “out-of-band” (OOB) from telecom and it became an established concept in IT infrastructure architecture.
- In the early 2010's we saw a centralization of IT complexity at the core, with the emergence of web-scale cloud data centers. Within those environments, use of distributed software and hyperconnected networks allow us to assume network disruptions as rare events that do not affect the availability of service. OOB remains important in enterprise data centers and in WAN networking, but the reliance on OOB declined in the largest data centers.
- As of 2019, we see IT complexity moving back to the edge and Telecom is borrowing back from IT (CORD) to cope with new bandwidth requirements, but neither the Telecom Architects nor the hyperscale IT architects remember the reasons why separation of the management plane was implemented in Telecom and in data centers decades ago.
So, we argue, as we architect CORD, we need to consider implementation of a resilient management plane that is analogous to the telecom SS7 and the Data Center OOB infrastructures. That management plane must be designed not only to enable remote human intervention, but also to extend the reach of other automated management systems to the infrastructure edge even (and especially) in the presence of data network disruptions.
