High-quality, scalable SIP trunking that connects your existing IP-PBX to the world over our vast private fiber network — with global reach, built-in redundancy, and fraud protection.
Carrier-grade
Trunk reliability
Burstable
Flexible capacity
Local & Toll-Free
DID number provisioning
Protected
Fraud monitoring
Your PBX · Our network · PSTN
Carrier-grade
Reliability
Any
IP-PBX
24/7
Local NOC
SIP trunking replaces aging phone lines with scalable, fiber-delivered voice — without touching the phone system you already own.
Crystal-clear calling carried over our private fiber backbone — no public-internet jitter or drops.
Keep every number. We port your existing local and toll-free DIDs, coordinated to minimize disruption.
Size channels to your call volume and burst when you need to — only pay for what you use.
Automatic rerouting and route diversity keep your trunks up even if a path goes down.
SIP trunking is the modern replacement for physical phone lines. Instead of copper PRI or T1 circuits, a SIP trunk delivers your voice calls digitally over an IP connection — linking the IP-PBX you already own to the public telephone network. Vast Networks runs your trunks across our private fiber backbone, so you keep your phone system, your numbers, and your workflows while gaining HD call quality, flexible capacity, and consolidated billing.
Traditional PRI and T1 lines lock you into fixed channel counts and rigid contracts — you pay for capacity whether you use it or not, and adding lines means a truck roll. SIP trunks are provisioned in software, so you scale channels up or down to match real call volume and burst during busy periods. The result is lower cost, faster changes, and no aging copper to maintain.
Many SIP providers route calls across the public internet, where congestion causes jitter, latency, and dropped audio. We carry your trunks over our own private fiber network with carrier-grade reliability and sub-5ms voice latency, so calls stay crystal clear. Built-in route diversity and automatic rerouting keep your trunks up even if a path fails.
SIP trunking works with any SIP-capable IP-PBX, so there is no need to replace the phone system you already invested in. We port your existing local and toll-free DIDs with zero downtime, provision new numbers nationwide, and provide E911 support — all on one consolidated, predictable bill.
Toll fraud can run up enormous bills in hours if a PBX is compromised. Every Vast Networks SIP trunk includes proactive fraud monitoring and prevention, with our 24/7 NOC watching for anomalous calling patterns and stepping in before a problem becomes an expense — so your voice stays secure as well as reliable.
Common questions about SIP trunking, channels, number porting, and fraud protection.
SIP trunking delivers your phone calls digitally over an IP connection instead of physical phone lines. It connects your existing IP-PBX to the public telephone network (PSTN), letting you make and receive calls over Vast Networks' private fiber backbone with HD quality and flexible, scalable capacity.
PRI and T1 lines are physical circuits with fixed channel counts and rigid contracts. SIP trunks are provisioned in software, so you can scale channels to match real call volume and burst during peaks — typically at lower cost, with faster changes and no copper to maintain.
Yes. SIP trunking connects to virtually any SIP-capable IP-PBX, so you keep the phone system you already own. There is no need to replace hardware — we connect your trunks, port your numbers, and you are up and running.
Absolutely. We handle no-hassle porting of your existing local and toll-free DIDs, coordinated to minimize disruption, and we can provision additional local and toll-free numbers as you grow.
Channels determine how many simultaneous calls your trunk can carry. We size your trunk to your concurrent call volume and offer burstable capacity for busy periods, so you pay for what you use rather than a fixed block of lines. Our team helps right-size it as part of your quote.
Every SIP trunk includes proactive fraud monitoring and prevention. Our 24/7 NOC watches for anomalous calling patterns and intervenes before unusual activity turns into a large bill, keeping your voice service both reliable and secure.
Tell us about your phone system and call volume. We'll size your SIP trunks, port your numbers, and send a quote.