The Avaya Midsize Solution Design examination assesses the proficiency of Pre-Sales Engineers and Network Architects in architecting comprehensive communication environments utilizing the Avaya IP Office platform. Candidates must demonstrate technical competency in integrating Avaya Equinox, Avaya Aura Messaging, and Avaya Session Border Controller for Enterprise within mid-market deployments. Mastery involves calculating bandwidth requirements, configuring SIP trunking protocols, and establishing high-availability redundancy models for unified communications. Furthermore, the assessment mandates expertise in implementing Avaya Spaces and Avaya IX Workplace alongside virtualization frameworks. Practitioners must validate end-to-end connectivity, QoS policies, and security parameters to ensure optimized voice, video, and collaboration performance across distributed enterprise networks.