The protocol that runs between the vSmart controllers and between the vSmart controllers and the vEdge routers, and unifies all control plane functions under a single protocol umbrella is the Overlay Management Protocol (OMP)12. OMP is a proprietary protocol that is designed to enable the Cisco SD-WAN solution, which provides a software overlay that runs over standard network transport, including MPLS, broadband, and internet to deliver applications and services3. OMP provides the following services12:
* Orchestration of overlay network communication, including connectivity among network sites, service chaining, and VPN or VRF topologies
* Distribution of service-level routing information and related location mappings
* Distribution of data plane security parameters
* Central control and distribution of routing policy
OMP is an all-encompassing information management and distribution protocol that enables the overlay network by separating services from transport. Services provided in a typical VPN setting are usually located within a VPN domain, and they are protected so that they are not visible outside the VPN. In such a traditional architecture, it is a challenge to extend VPN domains and service connectivity. OMP addresses these scalability challenges by providing an efficient way to manage service traffic based on the location of logical transport end points. This method extends the data plane and control plane separation concept from within routers to across the network2.
References:
1: Routing Configuration Guide for vEdge Routers, Cisco SD-WAN Release 20.x - Unicast Overlay Routing 2: Introduction to Overlay Management Protocol in Viptela 3: Cisco SD-WAN vEdge vManage vSmart IBM

The current time in enterprise networking history is characterized by the rapid pace of change in the network technologies, architectures, and services. Some of the factors that contribute to this change are:
* The increasing demand for network performance, scalability, reliability, security, and agility from the business and end users.
* The emergence of new network paradigms, such as software-defined networking (SDN), network function virtualization (NFV), cloud networking, and intent-based networking (IBN).
* The proliferation of network devices, applications, and data sources, such as the Internet of Things (IoT), mobile devices, cloud services, big data, and artificial intelligence (AI).
* The evolution of network standards, protocols, and best practices, such as IPv6, 5G, Wi-Fi 6, Ethernet, and network automation.
These factors create new opportunities and challenges for enterprise network designers, engineers, and administrators, who need to keep up with the latest trends and innovations, and adapt their network solutions to the changing business and technical requirements.
References:
Cisco Enterprise Network Architecture and Design,
https://www.cisco.com/c/en/us/solutions/design-zone/networking-design-guides/enterprise-networking-design.ht Enterprise Networking Explained: Types, Concepts & Trends,
https://www.bmc.com/blogs/enterprise-networking/2 : What is enterprise networking?,
https://www.cloudflare.com/learning/network-layer/enterprise-networking/3 : Enterprise WAN - A Brief History,https://blogs.juniper.net/en-us/enterprise-cloud-and-transformation/enterprise-wan-a-brief-history4

The node that enables Cisco ISE to share contextual information on a device with Cisco Stealthwatch is the pXGrid Controller. The pXGrid Controller is a component of the ISE Policy Service Node (PSN) that facilitates the exchange of contextual data between ISE and other security products, such as Stealthwatch, via the Platform Exchange Grid (pxGrid) protocol. The pXGrid Controller acts as a broker that registers, authenticates, and authorizes pxGrid clients, and allows them to publish and subscribe to topics of interest. For example, Stealthwatch can subscribe to the Session Directory topic to obtain user and device information from ISE, and use it to enrich the network flow data and provide better visibility and security analytics.
Stealthwatch can also publish topics, such as Rapid Threat Containment (RTC), to allow ISE to take mitigation actions on compromised endpoints, such as quarantine or re-authentication. References:
* Cisco Identity Services Engine Administrator Guide, Release 2.4 - Manage Platform Exchange Grid Services [Cisco Identity Services Engine] - Cisco1
* Deploying Cisco Stealthwatch 7.x with Cisco ISE 2.4 using pxGrid - Cisco Community2
* Stealthwatch - Networking fun3
* pxGrid in Depth > Sharing the Context | Cisco Press4

The overall health page of the assurance component in the Cisco DNA Center displays two primary categories: Client and Network1. The Client category shows the health score of all the wired and wireless clients connected to the network, along with the number of clients, the top issues affecting the clients, and the distribution of clients by type, OS, and SSID1. The Network category shows the health score of all the network devices, such as switches, routers, wireless controllers, and access points, along with the number of devices, the top issues affecting the devices, and the distribution of devices by site, family, and role1.
The other options are not primary categories on the overall health page. Server is not a category, but a type of client that can be filtered in the Client category1. Access-Distribution and Core are not categories, but roles of network devices that can be filtered in the Network category1. Wired is not a category, but a subcategory of the Client category that shows the health score of the wired clients only1.
References:
* Cisco DNA Assurance User Guide, Release 1.3.1.0 - Monitor and Troubleshoot the Health of Your Network [Cisco DNA Center]
* Designing Cisco Enterprise Networks (ENDESIGN) Exam Topics [Cisco]
* Cisco Validated Design Guides [Cisco]

The Cisco Catalyst 9500 Series Switches are specifically built to address the new challenges faced by enterprises, such as the need for increased bandwidth, security, and scalability. The Catalyst 9500 Series Switches are also designed to support Cisco SD-Access, which is a software-defined access fabric that simplifies network management and improves network security.
References: =
* Designing Cisco Enterprise Networks
(ENDESIGN): https://www.cisco.com/c/en/us/training-events/training-certifications/training/training-serv
* Cisco Catalyst 9500 Series
Switches: https://www.cisco.com/site/us/en/products/networking/switches/catalyst-9500-series-switches/in The Catalyst 9K platform has been built to address security risks posed by advanced persistent threats, operational complexities associated with IoT convergence, evolving mobility requirements and a need to take advantage of Cloud agility & consumption models.https://www.orbe.es/wp-content/uploads/2017/11/DNA_Bootcamp_SDA_CustomerLEO_Orbe.compress Slide 63