Expected 200-901 Exam Topics, as suggested by Cisco :

• Module 1: Software Development and Design: The topic covered include data formats (XML, JSON, and YAML), how to explain parsing of common data format (XML, JSON, and YAML) to Python data structures, describe the concepts of test-driven development, the contrast between various software development techniques such as waterfall or agile, and describing the advantages of organizing code into methods/functions, classes, and modules. Moreover, the topics covered include clone, add or remove, commit, push or pull, and merge conflicts.
• Module 2: Understanding and Using APIs: The topics in this domain of the exam including how to construct a REST API request to accomplish a task given API documentation, define common usage patterns related to webhooks, pinpoint the constraints when consuming APIs, explain common HTTP response codes associated with REST APIs, troubleshooting an issue for given the HTTP response code and pinpointing the parts of an HTTP response.
• Module 3: Cisco Platform and Development: In this module, the topics covered include how to create a Python script that uses a Cisco SDK given SDK documentation, define the capabilities of Cisco network management platforms and APIs (Meraki, Cisco DNA Center, ACI, Cisco SD-WAN, and NSO), explain the skills related to Cisco compute management platforms and APIs, describe the capabilities of Cisco collaboration platforms and APIs such as Webex, Webex devices, Cisco Unified Communication Manager including AXL and UDS interfaces, and explaining the capabilities of Cisco security platforms and APIs.
• Module 4: Application Deployment and Security: In this section, the advantages of edge computing are defined in addition to identifying attributes of different application deployment frameworks. It also covers how to identify the attributes of these application deployment types, virtual machines, bare metal, and containers. More topics covered include how to describe elements for a CI/CD pipeline in application deployments, construct a Python unit test, interpret contents of a Dockerfile, use Docker images in a local developer environment, and to identify application security issues related to secret protection, encryption (storage and transport), and data handling.
• Module 5: Infrastructure and Automation: The topics covered include how to describe the value of model-driven programmability for infrastructure automation, compare controller-level to device-level management, describe the use and roles of network simulation and test tools, explain the components and benefits of CI/CD pipeline in infrastructure automation, define foundations of infrastructure as code, the skills related to automation tools such as Ansible, Terraform, and Cisco NSO, identify the workflow being automated by a Python script. Moreover, the topics include how to pinpoint the workflow being automated by an Ansible playbook, pinpoint the workflow being automated by a bash script, interpret the outcomes of a RESTCONF or NETCONF query, YANG models, and a unified diff.
• Module 6: Networking Fundamentals: The topics covered include how to explain the purpose and usage of MAC addresses and VLANs, the purpose and usage of IP addresses, routes, subnet mask/prefixes, and gateways. It also covers topics such as explaining the function of switches, routers, firewalls, and load balancers and analyzes a basic network topology diagram with switches, routers, firewalls, load balancers, and port values. The topics also include the function of management, data, and control planes in a network device, the functionality of these IP Services: DHCP, DNS, NAT, SNMP, NTP, recognize common protocol port values including SSH, Telnet, HTTP, HTTPS, and NETCONF, and how to pinpoint the cause of application connectivity problems related to NAT, proxy, and VPN.