Recommended Dial Plan Type for Global Offices with Microsoft Lync Integration

C.

Based on the given scenario, the engineer needs to design a new dial plan that should work across multiple countries on four continents and integrate with a Microsoft Lync backend. So, the dial plan type that the engineer should recommend is SIP URI.

SIP URI (Session Initiation Protocol Uniform Resource Identifier) is a dial plan type that is used to create a unique identifier for a user or a device that can be used for routing calls over the internet. It is a protocol used for signaling and controlling multimedia communication sessions such as voice and video calls over IP networks.

Advantages of using SIP URI:

• It provides a global addressing scheme that can be used to route calls over the internet.
• It can be used to route calls to a specific user or device regardless of their location.
• It simplifies the dial plan by using a single addressing scheme for all locations and devices.
• It is compatible with various communication systems and devices, including Microsoft Lync.

H.323 is an older protocol that was used for voice and video communication over IP networks, but it is not recommended for use in modern communication systems. 164 is a type of dial plan that is used for international phone numbers, but it does not address the need for integration with Microsoft Lync. TEHO (Tail-End Hop-Off) is a call-routing technique used in Cisco Unified Communications Manager that is used to route calls to the PSTN (Public Switched Telephone Network) at the remote site instead of backhauling the call to the main site, but it is not a dial plan type.

Therefore, the best option for the given scenario is SIP URI.