Separate the pilot, DIDs, bindings and current proxy family
ThinkTel identifies a SIP trunk with a ten-digit pilot number that also appears in provider CDR and local-calling context. DIDs from other rate centres can be attached to that trunk, so the pilot is not every delivered DID. Each configured IP-address and port pair is a binding, and the public help centre documents up to eight IP addresses per trunk plus unique service-port requirements when an address is reused across trunks.
Preserve the pilot, affected DID, trunk, binding IP and port, PBX model, assigned proxy, media ranges, uControl order and current provider handoff. ThinkTel now recommends Toronto and Edmonton Perimeta SBCs while retaining legacy and OCS proxy guidance; do not copy addresses, ports or media rules between those families without confirming the selected binding.
Documented service facts
Reviewed 2026-10-20. Compare SIP trunk services →
Authentication
DocumentedThinkTel documents IP authorization against the pilot's configured binding and digest authentication for SIP requests requiring authorization. A wrong source can receive 403 and an absent or wrong digest can receive 401. Preserve binding, realm and challenge evidence without publishing secrets.
SIP registration
DocumentedThinkTel documents OPTIONS-based binding health and says this removes the need for REGISTER, which should be disabled whenever possible. A missing registration indicator is not a failure for a static binding; preserve the ordered handoff, Contact IP and OPTIONS state.
Inbound delivery
DocumentedThinkTel assigns a pilot to the trunk and can attach DIDs from other rate centres. Up to eight IP addresses may be associated, with each IP and port pair forming a binding. Pilot inventory, DID assignment, selected binding, edge receipt and PBX route remain separate evidence.
Inbound failover
DocumentedThinkTel separates Round Robin and Lowest Available binding selection from SureCall unavailable forwarding. SureCall can act when all bindings are down or when the PBX returns a documented trigger code. Preserve binding health, selection policy, response code, forward scope and destination.
Number and regional availability
Not verifiedThinkTel describes a Canadian network and lets eligible accounts order trunk DIDs by rate centre in uControl. The ordering guide directs customers to the orders team when inventory is absent. Exact availability, portability, activation, identity requirements, caller-ID rights and number features remain specific to number, account and date.
Audio codecs and DTMF
DocumentedThinkTel lists G.711 and G.729 as default trunk codecs and RFC 2833 for out-of-band DTMF. That capability statement is not proof of route availability, licensing, payload selection or transcoding. Capture the offer, answer, RTP endpoints, negotiated payload and DTMF result for representative inbound and outbound routes.
T.38 fax
Not verifiedThinkTel says renegotiation from G.711 to T.38 is accepted when supported for fax over IP. This does not establish both endpoints, every route, fallback, error correction or document reliability. Qualify the exact DID, direction, gateway, initial codec and approved document set, and keep the result scoped to that path.
Signaling and media encryption
Not verifiedThe reviewed trunk overview publishes UDP signaling and RTP firewall requirements for its documented proxies but does not establish a customer-trunk TLS profile, certificate validation, SRTP or downgrade policy. IP authorization is not encryption. Obtain supported protected transports and identities in writing and verify the negotiated customer-facing leg.
Concurrent calls and burst
DocumentedThinkTel documents channel activation, commit and burst plus per-binding maximum channels. These values remain separate from active calls, provider selection, OPTIONS health, call-start rate, codec bandwidth and PBX or SBC resources; no account capacity was tested.
Emergency calling
DocumentedThinkTel asks customers to update its 911 utility and coordinate live 911 testing in advance, with confirmation and a daily passcode. Emergency identity and address remain separate from pilot, DID, SureCall destination and ordinary regression testing.
Pricing model
Not verifiedThe reviewed public service and help-centre pages do not publish a complete current SIP-trunk rate card. Channel commit, maximum channels, DIDs, destinations, emergency service, forwarding and professional services can affect the account. Obtain a dated quote and preserve currency, billing increment, commitments, taxes, usage rates and renewal terms.
Administration and support
DocumentedThinkTel documents uControl binding orders, CDR downloads, permissions and status reporting. CDR filters and fields can correlate pilot, DID and time but do not prove customer-edge receipt, PBX routing, SDP agreement or two-way audio.
SMS and MMS
Not verifiedThe reviewed SIP-trunk, DID-ordering and uControl pages do not establish SMS or MMS on a trunk DID. A voice-capable number does not prove messaging eligibility, campaign registration, sender approval, consent, API behavior, throughput or fees. Verify the exact number and messaging program independently.
Keep authentication and REGISTER state distinct
ThinkTel documents both IP authorization against the configured pilot binding and digest authentication for SIP requests that require authorization. A request from an unconfigured source can receive 403, while absent or incorrect digest material can produce 401 and require a new authenticated request. The service overview separately says OPTIONS-based binding health removes the need for REGISTER and recommends disabling registration whenever possible.
Do not interpret a missing REGISTER state as a trunk failure when the ordered design uses static bindings. Preserve the provider-issued username, realm and binding without publishing secrets, then distinguish source authorization, digest challenge completion, OPTIONS response, inbound selection and PBX route as separate evidence.
Prove OPTIONS health and the configured binding-selection policy
The current service overview says ThinkTel sends a keep-alive OPTIONS request to the contact IP every 30 seconds. If it receives no response within 30 seconds, it sends requests every four seconds, disables that IP binding and stops sending new INVITEs there until a response arrives. ThinkTel separately documents Round Robin as the default distribution method and Lowest Available as a preferred-binding policy that advances when an earlier binding is full or unavailable.
Record each binding, proxy, OPTIONS request and response, provider-visible state, selection method, channel allocation and call timestamp. A call on a secondary binding does not by itself prove why the primary was skipped, whether a provider threshold was reached or whether an established call survived.
Separate binding failover from SureCall forwarding
ThinkTel describes two different outcomes: PBX-line failover can choose another configured binding, while Unavailable Call Forward or SureCall can send a call to a supplied telephone destination. SureCall can act when all bindings are down, and the provider also publishes a bounded list of SIP response codes that can trigger an unavailable forward without waiting for every binding to become unresponsive.
Preserve whether forwarding is set at trunk or DID scope, the destination, the selected binding, the exact response code and the provider change record. An answer at a SureCall number is not proof that another SIP binding was tried, that the primary recovered or that the PBX accepted the original request.
Correlate provider CDRs with edge and PBX evidence
ThinkTel documents uControl CDR downloads with filters, sorting choices, time zone, date range and fields including billing number, source, destination, duration, channel count and line type. Those records can correlate a pilot, DID and time window, but they do not prove which customer interface received an INVITE, which dialplan route loaded, what SDP was accepted or whether audio was bidirectional.
Match one provider record to an authorized edge trace. Preserve source, Request-URI, To, asserted identity, Via, Contact, digest exchange, SDP and response sequence. Then follow PJSIP identify, endpoint, transport, context, digit normalization and the first loaded Asterisk or FreePBX route.
Bound capacity, media, emergency and compatibility claims
ThinkTel documents channel activation, per-binding maximum channels, G.711, G.729, RFC2833 and conditional T.38 renegotiation. These are published service settings, not proof of one account's channel commit, burst, negotiated codec, DTMF result, fax delivery or PBX capacity. Historical Asterisk-oriented canreinvite guidance is not represented as a current universal PJSIP configuration.
ThinkTel asks customers to update its 911 utility and coordinate any live 911 test in advance, with confirmation and a provider-issued daily passcode. Do not use an emergency call as a routine regression test. No account, binding, call, media path, SureCall event, emergency result, price, availability or compatibility was inspected or tested.
Sources & applicability
Primary references for the technical details above. Operational examples and planning checklists are VoIP.info editorial guidance.
- ThinkTel network and services ↗
- ThinkTel SIP trunk service overview ↗
- ThinkTel SIP trunk help centre ↗
- ThinkTel SIP authentication ↗
- ThinkTel IP-binding workflow ↗
- ThinkTel SIP failover ↗
- ThinkTel SureCall response-code triggers ↗
- ThinkTel binding and SureCall trigger guidance ↗
- ThinkTel SIP trunk IP-binding limit ↗
- ThinkTel channel commit and burst ↗
- ThinkTel DID ordering ↗
- ThinkTel pilot-number role ↗
- ThinkTel caller-ID guidance ↗
- ThinkTel 911 testing procedure ↗
- ThinkTel uControl permissions ↗
- ThinkTel CDR download ↗
- ThinkTel service status ↗
Examples require adaptation to your topology. No live PBX or hardware testing is claimed.