Cisco’s partner program currently contains four specializations. Besides having multiple individuals owning certain “regular” certifications like a CCNP or CCIE, also additional exams are required to fulfill certain roles and achieve the specialization.

One of those additional exams is called “Enterprise Networks Core and WAN Exam (ENCWE)” with number 500-452. Besides the blueprint itself and a full-blown training Cisco does not provide specific content for this exam.

I have recently passed this exam and, without breaking the NDA, I highly recommend you to watch and study the materials presented in the following two Cisco Live sessions:
BRKCRS-2002 IWAN Design and Deployment Workshop
BRKARC-2091 Emerging Trends in Branch Office Architectures

Doing so, in addition to a quick refresher on the CCDP content, was sufficient for me to pass this exam. Good luck with your studies!