Phone

SIP Trunks: flexible voice connectivity over IP.

Replace legacy phone lines with SIP trunks that connect your PBX or UC platform to the public phone network using your data connections.

Modern trunks for modern PBXs

SIP trunks let you scale channels, add numbers, and adjust routing more easily than with fixed PRI or analog lines.

Connect your phone system to the world over IP

SIP trunks use your IP network to carry calls, often lowering recurring costs and simplifying how you manage capacity across locations.

You keep your PBX or UC platform while modernizing the way voice traffic flows in and out.

SIP Trunks features

Voice over IP connectivity

Use IP connectivity instead of bundles of physical phone lines to carry calls.

Scalable channels

Increase or decrease concurrent call capacity with configuration changes, not new circuits.

Number options

Support local, toll‑free, and international numbers as your footprint grows.

Resilience features

Design trunk failover and rerouting to keep calls flowing during incidents.

Where SIP Trunks work best

Centralized PBX hubs

Feed many sites through centralized SIP trunking at core locations.

Contact centers

Combine flexible channel counts with advanced routing and reporting tools.

Global calling needs

Use local numbers and SIP trunks to build a global presence without many physical lines.

PBX / UC migrations

Use SIP trunks that can span legacy and new platforms during transitions.

How SIP Trunks connect to your PBX

SIP trunks use IP connectivity between your PBX or session border controller and the provider, replacing groups of legacy digital or analog circuits.

Call setup and teardown follow SIP standards, while media flows over IP with codec and encryption options.

Typical trunk path

IP PBX / SBC → SIP trunk over Internet/Ethernet → Provider core → PSTN & other SIP endpoints.

SIP Trunk examples

SIP is usually priced by channels, minutes, and numbers. These examples show typical groupings.

10–20 channel bundle

For small offices or single sites.

  • 10–20 concurrent calls.
  • Local and long‑distance options.
  • Supports one PBX.

50–100 channel bundle

For larger offices or call centers.

  • 50–100 concurrent calls.
  • Geo‑redundant options.
  • Multiple number ranges.

Burst / elastic

For variable or seasonal demand.

  • Baseline channels plus burst.
  • Pay‑as‑you‑grow capacity.
  • Great for events or campaigns.

Business benefits of SIP Trunks

Cost efficiency

Reduce spend on fixed line bundles and long‑distance charges.

Scalability

Scale channels up or down without truck rolls or new cards.

Continuity options

Reroute calls to backup sites or numbers during outages.

SIP Trunks FAQs

Will SIP Trunks work with our existing PBX?

In many cases SIP can be integrated via native interfaces or a session border controller; compatibility is validated as part of design.

How do we size the number of channels?

Historical call volumes, concurrency, and growth expectations are analyzed to recommend a starting channel count and headroom.

Ready to modernize your trunking?

Design a SIP trunk plan around your voice platform.

Share your PBX/UC details, sites, and call patterns. Get a SIP trunk design with capacity, resilience, and migration steps.

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