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sipgate trunking UK: registered PBX, asymmetric channels and cleartext boundaries

Separate PBX registration, account-assigned numbers, incoming and outgoing channel limits, UK emergency locations and explicitly unencrypted trunk transport.

Reviewed 2026-10-07sipgate UK trunking product, service, plan, network, encryption, FreePBX, emergency and price pages reviewed October 7, 2026; the active account, order and current terms govern, and no account, credential, registration, number, port, location, plan, PBX, firewall, VPN, signaling path, media stream, call, fax, message, availability, compatibility, price or support response was inspected or testedAdvancedDocumentation based · not lab tested

Keep the UK trunk and registered PBX identity explicit

sipgate describes trunking as registering the whole telephone system rather than each phone. Preserve the exact UK product, trunk identity, registrar, credential owner, accepted Contact, refresh result and number assignment. Do not mix sipgate UK trunking with sipgate business users, sipgate Germany or the separate sipgate.io and API products.

A successful PBX REGISTER proves only the observed binding. It does not prove every inbound number reaches the right route, every outbound identity is authorized, media traverses the firewall or the purchased plan has spare capacity.

Documented service facts

Reviewed 2026-10-07. Compare SIP trunk services →

SIP authentication

Documented

sipgate describes the entire PBX registering for trunk communication rather than each handset. Treat the trunk's SIP ID, password, registrar realm and authorized caller identities as separate secrets and policies. The reviewed public pages do not establish source-IP authentication as a substitute for registration.

SIP registration

Documented

The current overview says the PBX registers as a whole. Preserve the exact registrar, resolved addresses, Contact, refresh interval, granted expiration, NAT path and response from the provisioned account. A successful REGISTER does not establish inbound number assignment, outbound identity acceptance or media reachability.

Inbound delivery

Documented

The account assigns one or more numbers or number blocks to a trunk. The FreePBX guide distinguishes account-side number assignment from PBX inbound routes. Preserve the ordered inventory, port state, delivered Request-URI and headers, selected trunk and final dialplan destination; the product page does not establish number availability or port acceptance.

Routing and failover

Not verified

The reviewed trunking pages do not establish one automatic PBX failover, alternate destination, DNS failover, response-code retry or established-call survival design. Obtain the account's current routing and continuity controls and run an approved new-call test; do not import sipgate business-user routing features into the trunk record.

Number and regional availability

Documented

sipgate UK documents UK trunk numbers and number porting, but public product and price pages do not establish inventory, geographic eligibility, port acceptance or activation date for a specific customer. Keep the UK trunk service distinct from sipgate Germany and other sipgate products.

Audio codecs

Not verified

The current trunk pages and plan table do not publish one complete codec, packetization, DTMF, transcoding or media-anchoring profile for every account. The FreePBX page exposes codec selection as a PBX step rather than a provider acceptance matrix. Preserve SDP offer and answer, selected codec, DTMF method, RTP endpoints and decoded audio per direction.

T.38 fax

Not verified

The reviewed first-party trunking sources do not establish T.38 entitlement, G.711 pass-through requirements, redundancy, page limits or gateway behavior for this service. Validate the exact fax design and retain negotiation and delivery evidence; do not transfer a claim from sipgate business, an ATA or a PBX template.

Signaling and media encryption

Documented

sipgate's current help article explicitly says sipgate trunking does not offer SRTP or TLS voice encryption and that calls are transmitted without encryption; it mentions a VPN as a possible alternative. The separate network reference says provider-originated SIP uses UDP port 5060. A VPN design, access policy and observed tunnel remain customer-specific evidence, not an encrypted-trunk claim.

Concurrent calls and call starts

Documented

The March 27, 2026 plan reference lists seven plans with 1, 2, 5, 10, 25 or 50 concurrent incoming lines and says all offer 100 outgoing lines. These are plan limits, not measured simultaneous calls or call-start throughput. The older overview still describes only three contract sizes, so use the active account and current order as authority.

Emergency calling

Documented

sipgate's emergency regulations require a correct, valid UK address and activation of the emergency location; they warn that service, power or Internet outages can prevent access and instruct customers not to place test calls. Preserve every number-to-location assignment, verification state, update owner, user notice and an alternative means of calling; follow provider-approved validation only.

Pricing model

Documented

The current public tariff page lists monthly Starter, Regular, Plus and Enterprise 10 charges exclusive of VAT, while the March 27 plan guide also lists Developer, Enterprise 25 and Enterprise 50. Pricing and inclusions can change and the two public tables are not identical. Use the dated account order and invoice for plan, incoming lines, outgoing limits, numbers, ports, calls, VAT and cancellation.

Administration and support

Documented

The current overview places trunk location, status, consumed minutes and call restrictions in the logged-in trunk page and says plans can be changed online. The reviewed public sources do not establish one support response target, role model, maintenance window or escalation path. Preserve named administrators, MFA and credential policy, current contacts and signed terms.

SMS and MMS

Not verified

The reviewed trunking product and plan pages do not establish SMS or MMS entitlement on trunk numbers, sender registration, API access, throughput, webhook security, retention or price. Keep adjacent sipgate business SMS and sipgate.io/API offers outside this trunk record unless the active order explicitly includes them.

Model incoming and outgoing limits independently

The March 27, 2026 plan guide lists Developer, Starter, Regular, Plus and Enterprise plans with 1, 2, 5, 10, 25 or 50 incoming lines, while saying every plan offers 100 outgoing lines. An older service overview still summarizes three contract sizes. Use the active account and current order rather than combining those tables into a new entitlement.

Incoming lines, outgoing lines, active calls, attempted call starts, destination restrictions, PBX channels, media bandwidth and firewall state are different limits. A plan label is not a measured call-start rate or successful load test.

Treat number assignment and caller identity as policy

The current FreePBX guide says multiple phone numbers can be assigned to one trunk and that inbound numbers are selected in the sipgate account. It also says outbound caller ID must be one of the account's numbers and describes an E.164-formatted P-Preferred-Identity for that configuration. Preserve the assigned inventory, presented identity, request headers and provider result rather than assuming arbitrary CLI is accepted.

Keep number availability, port acceptance, account assignment, PBX inbound routing and displayed caller identity as separate evidence. A dial pattern that sends all digits to the trunk also needs an explicit authorization and emergency-routing review.

Record the cleartext trunk boundary and dated network data

sipgate's current help page explicitly says the trunk product does not offer SRTP or TLS voice encryption and that calls are transmitted without encryption; it points to a VPN as a possible alternative. A VPN can protect one designed path, but it does not change the provider trunk into native TLS or SRTP or prove end-to-end protection beyond its tunnel.

The network article lists UDP port 5060 and signaling and RTP addresses, but its body is dated March 15, 2017 and warns that ranges can change. Treat that page as dated configuration evidence. Use current provider guidance and observed logs for an allowlist, preserve IPv4 and IPv6 requirements, and never open the PBX broadly to compensate for one-way audio.

Bind emergency calling and price to current records

sipgate's emergency regulations require a correct UK address and activated emergency location, warn that service, power or Internet outages can block access, require user notice and explicitly say not to place test calls. Maintain a verified number-to-location record, update owner and alternative means of calling, and use only provider-approved validation.

The public tariff page currently lists monthly Starter, Regular, Plus and Enterprise 10 amounts exclusive of VAT, while the plan guide also includes Developer, Enterprise 25 and Enterprise 50. Neither page is an invoice or serviceability result. Use the dated order, active account and current terms for limits, numbers, ports, usage, VAT, renewal and cancellation. No account, trunk, call, media, fax, message, emergency workflow, VPN, availability, compatibility, price or support response was tested for this guide.

Sources & applicability

Primary references for the technical details above. Operational examples and planning checklists are VoIP.info editorial guidance.

Examples require adaptation to your topology. No live PBX or hardware testing is claimed.

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