Reference
Al-shawi, Marwan, CCDE Study Guide (Cisco Press, 2015)
As a network designer, understanding the purpose and goal of the network is critical to properly designing it. This sample chapter from Cisco Certified Design Expert (CCDE 400-007) Official Cert Guide maps to the CCDE v3.0 Unified Exam Topics Section 4.0, "Service Design," and covers the service design topics—from business applications and service models, to the cloud and data management—you need to meet business objectives.
Al-shawi, Marwan, CCDE Study Guide (Cisco Press, 2015)