Business SIP Trunking with AT&T IP Flexible Reach

Consolidate your voice and data with a SIP trunking solution that delivers outbound, inbound, local and long distance calling with advanced calling features and management for businesses utilizing existing premises-based telephony equipment.

Digital, cloud, and business services

Avanade’s network architecture for voice presented a variety of challenges for their collaboration platform, Microsoft Teams. With most of their employees working beyond the office, enhancing their ability to collaborate was critical.

Read the case study (PDF)

AT&T IP Flexible Reach benefits

Integrate voice and data into one integrated access circuit

  • Optimize network capacity 

    Combine voice and data over integrated access and simplify network management.

  • Utilize your current equipment 

    Avoid investing in new equipment for voice lines.

  • Control costs 

    Increase and decrease the number of concurrent call channels and only pay for the number of lines you need.

  • PBX Integration

    Add SIP trunking to your existing PBX such as Microsoft Teams to connect to the Public Switched Telephone Network (PSTN).

  • Maintain call quality  

    Benefit from calls carried on the AT&T MPLS network, not public internet.

  • Avoid toll charges

    On-net (VoIP to VoIP) calls route within the IP network and don’t incur additional charges.


Better utilize network capacity

Combine voice and data into a dynamic network that integrates with existing PBX equipment

Features Details
Flexible calling plans  Includes calling plans that support inbound and outbound calling
Branch office extensions Share trunks across multiple locations.
Virtual telephone numbers (VTNs) Establish local visibility by assigning a telephone number to a phone not physically located within your location’s local calling area. 
Web-based portal  Web-based performance reporting, call detail reporting, e-ordering.
Integration to PBXs such as Microsoft Teams Brings together your premises PBX or your cloud-based Microsoft Teams PBX with AT&T’s highly reliable global network.

Get business grade voice for Microsoft Teams

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You must use either AT&T Dedicated Internet Service (ADI) or AT&T Virtual Private Network (AVPN) for high-speed dedicated access. 

There is no limit on the number of calls that the service can originate per second. 

Eases integration and management for a feature-rich set of voice and collaboration tools with optional calling plans. Use your premises-based Microsoft Teams certified Session Border Controller (SBC) or have it hosted and managed by AT&T.  Plus, no need to port your telephone numbers for existing IP Flexible Reach customers.


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