Role 1 — Teams Telephony / Voice Consultant Must-have (core): • Teams Phone (Phone System) architecture — deep on Direct Routing; knows how it differs from Operator Connect and Calling Plans, and why Direct Routing is the right fit here (customer + telco + SBC). • Hands-on SBC configuration — AudioCodes (Mediant) and/or Ribbon/Sonus (SBC Core / SWe): trunks, IP profiles, coders, routing rules, HA/failover. • SIP & SIP trunking — SIP signaling, SDP, codecs (G.711/OPUS), transcoding, media bypass; ability to read a SIP ladder. • Direct Routing plumbing — PSTN gateways, voice routes, PSTN usages, online voice-routing policies. • Dial plans & number normalization — tenant dial plans, regex normalization rules, effective dial plan validation. • Telco/carrier coordination — working the SIP trunk, DID ranges, and number porting with the telco provider. • Emergency calling — E911 / dynamic emergency calling, Location Information Service. • Voice troubleshooting — SBC logs, syslog/Wireshark traces, Teams call analytics / Call Quality Dashboard. • Voice apps — resource accounts, auto attendants, call queues, caller-ID policies. • Voice networking — TLS/SRTP certificates, firewall/NAT, QoS, media ports. Nice-to-have: MS-720 (Teams Voice Engineer) cert; AudioCodes/Ribbon vendor certification; SBC redundancy/HA design; contact-center or analog/SIP gateway integration experience.