Name the ordered service and authority for every control
AireSpring publishes a current SIP Trunking page, Local SIP Trunk terms inside its Master Service Agreement and a separately named Long-Distance SIP Trunking product. Preserve the current quote, order, service schedule, implementation worksheet, product name, service address and customer edge before importing a PBX template or a control described on another product page.
The 2023 data sheet and 2022 infographic describe portal rerouting, disaster-recovery and DTO capabilities. Retain their revision dates. They are useful planning evidence, but neither proves that one current account exposes the same control, destination types, trigger, timer or restoration behavior.
Documented service facts
Reviewed 2026-10-22. Compare SIP trunk services →
Authentication
Not verifiedThe Local terms describe routing to a customer IP address, but the reviewed public sources do not publish one universal registrar, credential, source-IP, SBC, transport or certificate contract. Use the accepted implementation handoff; an IP-address reference is not proof of IP-only authentication.
SIP registration
Not verifiedNo reviewed public record establishes that every ordered AireSpring trunk registers or publishes a universal registrar, username, expiry or Contact behavior. Preserve the exact product, peer set, trust method and account confirmation instead of manufacturing registration credentials.
Inbound delivery
DocumentedLocal service uses AireSpring-supplied or ported numbers and SIP delivery to the customer gateway or IP-PBX. Preserve number and port state, active account route, provider attempt, Request-URI or called identity, edge receipt and PBX destination separately.
Inbound failover
Not verifiedThe dated data sheet describes AireCare manual, percentage and time-of-day rerouting; the dated infographic and current Long-Distance page describe DTO. The current order must establish which controls apply, their destinations, triggers and restoration behavior.
Number and regional availability
DocumentedAireSpring's current product page lists DIDs, toll-free service, number porting and international calling, while the Local service terms limit use to numbers supplied by or ported to AireSpring. These statements do not prove inventory, portability, address eligibility or installation interval for a requested number. Obtain a dated orderability and port result for every location.
Audio codecs and DTMF
Not verifiedThe current product page advertises HD audio where available, but the reviewed public materials do not define the exact codec list, DTMF mode, packetization, transcoding or downstream PSTN behavior for an account. Confirm the ordered media profile and inspect the actual SDP offer, answer and telephone-event payload on authorized calls; an HD-audio headline is not a negotiated result.
T.38 fax
Not verifiedThe reviewed SIP Trunking product, data-sheet and Local service terms do not establish T.38, G.711 fax pass-through or an acceptance workflow. AireSpring publishes separate POTS-replacement and device material, but those capabilities are not transferred to this trunk. Qualify fax independently for the exact number, gateway, direction, document set, switchover and fallback.
Signaling and media encryption
DocumentedThe current product page lists TLS and SRTP options. Confirm the ordered service, peer hostname, certificate validation, TLS version, SRTP profile, keying and fallback; option availability and one successful handshake do not prove protected media.
Concurrent calls and burst
DocumentedCurrent Local terms define one concurrent call per SIP trunk and allow multiple DIDs. That is not a public calls-per-second limit, universal account total or proof that any particular busy response invokes DTO; preserve purchased count, active calls, new attempts and responses separately.
Emergency calling
DocumentedThe product page lists E911, and the current service terms require the telephone number associated with the registered address in the SIP From URI user part for SIP Trunking 911. The terms also describe power, broadband, address and routing limitations. Confirm eligibility, exact number, authorized outbound identity, validated civic address, callback route and provider-approved test method; never place an uncoordinated live emergency test.
Pricing model
Not verifiedThe current product page describes flexible pricing but does not publish a complete account quote. Older state tariffs and unrelated Long-Distance rate descriptions are not a current universal price. Obtain dated terms for trunks, channels, directions, destinations, numbers, porting, E911, failover, encryption, taxes, support, commitment, renewal and termination.
Administration and support
DocumentedPreserve product, order, implementation worksheet, number and port state, portal entitlement, saved routes, DTO destination, change timestamps, provider attempt, ticket and restoration. Dated portal material and another product page are not current account state.
SMS and MMS
Not verifiedThe reviewed SIP Trunking product, data sheet and Local service terms do not establish SMS or MMS entitlement on trunk numbers. Voice-number service does not prove messaging eligibility, registration, consent controls, API delivery, throughput, retention or fees. Verify a separately identified messaging product and each exact number before representing support.
Keep the IP handoff separate from authentication and registration
The Local terms describe traffic routed between the customer IP address and the PSTN or another IP address, delivered to a gateway or IP-PBX using SIP. The reviewed public material does not publish one universal registrar, credential format, source-address rule, SBC pair, transport or certificate contract.
Obtain the assigned peers, permitted customer addresses, transport, ports, trust method and registration requirement from the implementation handoff. A configured trunk, registered object, permitted source, reachable peer and accepted call remain different evidence states.
Trace the DID, portal route and DTO destination independently
The Local terms limit service use to numbers supplied by or ported to AireSpring. The dated data sheet describes AireCare rerouting, percentage allocation, manual and time-of-day routing, while the dated infographic describes DTO as a feature add-on that can send inbound calls to a designated number when a circuit is down or lines are occupied. The current Long-Distance page also describes DTO and flexible routing.
Do not combine those records into one universal Local-trunk workflow. Preserve the exact DID, port state, active account route, control owner, change timestamp, normal destination, DTO destination, provider attempt and customer-edge receipt.
Separate concurrent calls, call attempts and overflow
The current Local terms say each SIP trunk enables one concurrent call and may expose multiple DIDs. That is an active-call unit, not a published calls-per-second limit, a universal account total or proof that every busy condition invokes DTO. Obtain the purchased trunk count, directional or shared scope, call-start limit, overload response and overflow treatment from the order.
For one disputed call, retain the active-call count, new attempt, first SIP response or timeout and any later provider route. A 486, 503, timeout, local PBX rejection and provider-capacity result have different owners and must not be flattened into “all trunks busy.”
Treat TLS, SRTP and HD audio as ordered and negotiated evidence
The current product page lists TLS and SRTP options and HD audio where available. The dated data sheet and infographic also describe protected signaling and media. Confirm the ordered option, assigned hostname, certificate name and chain, peer validation, TLS version, SRTP profile, keying and fallback behavior.
Retain the actual SIP offer and answer, selected codec, packetization, DTMF payload, RTP endpoints and protected-media result. Marketing availability, a loaded certificate or a successful TLS handshake does not prove SRTP, wideband audio, decoded two-way media, fax or messaging.
Bind emergency, compatibility and acceptance to the account
The current product page lists E911, number porting, toll-free and international calling. The Local terms require AireSpring-supplied or ported numbers, a legitimate service address for listed features and document equipment and broadband compatibility limitations. Preserve each eligible number, validated civic address, authorized outbound identity, callback route and provider-approved non-live test procedure.
Accept normal inbound and outbound calling, approved capacity behavior, authorized rerouting, restoration, DTMF and both media directions separately. Obtain dated commercial terms for trunks, usage, numbers, porting, routing controls, emergency service, support, taxes, renewal and termination. No account, route, call, failover or emergency workflow was tested for this guide.
Sources & applicability
Primary references for the technical details above. Operational examples and planning checklists are VoIP.info editorial guidance.
- AireSpring SIP Trunking ↗
- AireSpring SIP Trunking data sheet, revision May 12, 2023 ↗
- AireSpring Master Service Agreement ↗
- AireSpring Long-Distance SIP Trunking ↗
- AireSpring data-sheet index ↗
- AireSpring Top 10 Reasons for SIP Trunking infographic, revision July 5, 2022 ↗
- AireSpring SIP Trunking data sheet ↗
Examples require adaptation to your topology. No live PBX or hardware testing is claimed.