XOS brings the Everything-as-a-Service (XaaS) organizing principle to the CORD architecture. In doing so, it addresses several of CORD's high-level design requirements, including a means to seamlessly integrate control plane (SDN) and data plane (NFV) based services; the ability to support both access services and conventional cloud services; support for multiple security domains; and the "end-to-end glue" needed to make CORD both extensible and controllable.
XOS is a central part of NEM (Network Edge Mediator), which plays a role in both SEBA and COMAC. XOS is a stand-alone tool, with other use cases on the horizon (e.g., multi-cloud service mesh).
For more information see:
- Breaking the Disruptor's Dilemma.
- Describes how NEM and XOS can be used to automate the operationalization of a set of disaggregated components.
- XOS: Extensible Service Control Plane.
- Describes XOS as a self-contained service that augments micro-service based cloud applications built around systems like Kubernetes.
- Beyond Micro-Services: CORD's Model Driven Design.
- Describes CORD’s model-driven design, and XOS's role as a service control plane layered on top of a collection of micro-services. (Slide Deck)
- XOS Guide.
- Describes XOS support for defining and processing models.
- VTN and Service Composition.
- Describes CORD's model for service composition and the interaction between XOS and VTN to realize it.
- Security in CORD.
- A brief introduction to CORD's security architecture.
- Service Assembly and Composition in CORD.
- An architectural description of how CORD models functionality as the composition of scalable multi-tenant services. (Historical. Above documents make it partially obsolete.)
NEM: Network Edge Mediator
The following is a high-level depiction of NEM and how it fits in SEBA. In summary, NEM consists three subsystems: (1) XOS, (2) a set of monitoring and logging micro-services (Elk Stack, Kibana, Prometheus, Grafana), and (3) a Kafka bus. Backend components like VOLTHA, ONOS, and Control Apps running on ONOS (not shown) take directives from NEM (downward black arrows) and push monitoring and logging events to NEM (upward black arrows).
For more information on NEM, including the role XOS plays in NEM and the role NEM plays in SEBA, see the following presentations:
- Logging and Monitoring in CORD. ONF Connect 2018
- XOS: The Service Composition and Management Layer for CORD and SEBA. ONF Connect 2018
- NEM: Overview and ISSU Plans. SEBA Engineering Meeting, February 2019.
- SEBA Overview. February 2019
