Introduction to Multidomain
A common trend arising in the industry is data being generated and stored in many areas of the network. Traditionally, a majority of the data for a business was stored in a centralized data center. With the influx of guest users, mobile devices, bring your own device (BYOD), and Internet of Things (IoT), data is now being generated remotely in a distributed manner. This means the industry is shifting from data centers to multiple centers of data. That being said, simple, secure, and highly available connectivity is a must to allow for enhanced user and application experience. The other big piece to this is having a seamless policy that can go across these multiple centers of data. An example of this is policy that extends from the campus environment across the WAN and into the data center and back down to the campus. This provides consistency and deterministic behavior across multiple domains. Figure 1-14 illustrates a high-level example of sharing policy between a campus branch location and a data center running Cisco Application Centric Infrastructure (ACI).
FIGURE 1.14 High-Level Multidomain Example
In future evolutions of Multidomain, the common policy will consequently provide end-to-end policy management across all three domains. This gives the capability of leveraging things like application SLAs from the data center to the WAN and back. This ensures the applications are performing to the best of their ability across the entire network, relieving strain on the WAN and providing a better user experience when using the applications. Figure 1-15 shows a high-level example of what this could look like from a topology perspective.
FIGURE 1.15 High-Level Multidomain and SD-WAN Example
Multidomain offers the capability to have the network operate as a holistic system, as mentioned previously in this chapter. This takes intent-based networks to the next level by taking policy across all domains for a seamless application experience. This also implements security everywhere and provides complete granularity in terms of control and operations.