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Cisco SDA - Components

Cisco Software Defined Access is a new paradigm towards building Enterprise Networks. Primarily built upon the Cisco's DNA Center software, it leverages several next-generation components to design, provision and apply policy to create an intelligent wired and wireless network infrastructure.

Cisco DNA Assurance which turns the network devices into sensors, giving visibility to everything on the network; guided remediation which automates resolution to keep the network at its optimal performance and thereby improve the end user experience, are some of Cisco's USPs.

Cisco SDA accomplishes this intent based networking via the following components:

  1. Fabric Control Plane nodes: Based on LISP map-server and map-resolver functionality combined together on the same node, control plane node (database) tracks the endpoints in the fabric site and associates the endpoints to fabric nodes. Border nodes and edge nodes register with the control plane nodes.
    Control Plane node can be dedicated or can be co-located with border node (explained later).
  2. Edge Node: Equivalent of the access switches in a traditional campus LAN design. The edge nodes however implement a Layer 3 access design.
  3. Intermediate Node: These nodes are a part of Layer 3 network used for interconnections between edge nodes and border nodes. Analogous to the distribution switches in the traditional campus network design. Intermediate nodes route and transport IP traffic inside fabric.
  4. Border Node: The fabric nodes serve as a gateway between the SDA fabric and the networks external to the fabric. It serves as a common exit point from the fabric for access to the rest of the network (outside the SDA fabric) and Internet.
  5. Fabric Wireless LAN controllers: Apart from the normal non-fabric WLC functions such as access point image and configuration management, mobility etc., fabric WLCs provide services such as fabric integration -- Register MAC addresses of wireless clients into the host tracking database of the fabric control plane during new wireless client joins and providing fabric edge RLOC location updates for roaming clients.
  6. Fabric Access Points: Fabric mode APs are associated with fabric WLC (above) and have one or more fabric-configured SSIDs. Fabric APs must be directly connected to the fabric edge node switch to enable fabric registration, RLOC assignment via WLC etc. CDP runs between fabric APs and fabric edge nodes to apply special port configurations.
  7. Identity Services Engine: Cisco's famous NAC solution which integrates with Cisco DNA Center using Cisco's Platform Exchange Grid (pxGrid), to provide visibility for the users and the groups in a simple interface while also facilitating end to end security policy management.
  8. Cisco DNA Center: The Godfather that pulls all the strings and holds all the components together. The Cisco DNA Center software, including the SD-Access application package, is designed to run on the Cisco DNA Center Appliance.


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