Order the access model before choosing a PBX template
Zayo's current product page names private access, over-the-top access, Microsoft Teams Direct Routing and Webex SIP trunks as deployment options. Those are different service and demarcation choices, not aliases for one generic SIP interface. Record the exact ordered product, customer and provider edge, access circuit or public path, SBC ownership, peer addresses and responsible support team before configuring the PBX.
The reviewed public pages do not establish one universal digest, source-IP, certificate or REGISTER model. A Zayo customer login or portal record is management evidence, not a SIP credential. Use the current implementation worksheet and loaded PBX objects, then preserve source, destination, transport, identity and response evidence for each direction.
Documented service facts
Reviewed 2026-10-06. Compare SIP trunk services →
SIP authentication
Not verifiedThe reviewed public material does not publish one universal digest realm, credential lifecycle, mutual-certificate procedure or source-address authorization rule. Private access, over-the-top access, Microsoft Teams Direct Routing and Webex SIP trunks are named deployment options, not one shared PBX authentication template. Obtain the current implementation worksheet.
SIP registration
Not verifiedThe reviewed product and overview pages do not establish whether every Zayo SIP order uses REGISTER, fixed peers, an SBC handoff or another binding model. Record the exact ordered service, peer addresses, transport, registration requirement, contact ownership and source restrictions rather than importing a generic configuration.
Inbound delivery
DocumentedZayo describes SIP Solutions as connecting an on-premises or cloud PBX to the PSTN and offers private, over-the-top, Teams Direct Routing and Webex SIP-trunk deployment options. The public pages do not expose a universal number-to-destination workflow; preserve the assigned number, access model, ingress peer, delivered identity, PBX match and final route separately.
Routing and failover
DocumentedZayo markets an owned network, geo-redundancy, disaster-recovery options and portal reroutes. Those statements do not establish the account's route order, retryable SIP responses, timers, destination health check, restoration sequence, access-path independence or survival of established calls. Convert the contracted design into coordinated new-call tests.
Number and regional availability
DocumentedThe current SIP Solutions page states service for enterprises across the United States and Canada and says Zayo delivers more than two million phone numbers. That establishes a broad service footprint, not current inventory, portability, number rights, regulatory eligibility or coverage for a specific location and number type. Use a dated order result.
Audio codecs
Not verifiedThe reviewed public sources do not publish one production interface's codecs, packetization, DTMF method, transcoding policy or media addresses. Broad quality and HD-voice language elsewhere in the portfolio does not define the negotiated media for a SIP Solutions trunk. Obtain the exact interface specification and retain the actual offer and answer.
T.38 fax
Not verifiedThe reviewed SIP Solutions, overview, access and explainer pages do not establish T.38 support, G.711 pass-through behavior or a fax guarantee for the ordered trunk. Confirm the exact gateway mode, switchover, codec, page profile and delivery report rather than transferring capability from another Zayo or partner service.
Signaling and media encryption
DocumentedZayo's current SIP explainer says encrypted SIP services use TLS and SRTP. The public material does not define the hostname, certificate-validation procedure, SRTP profile, cipher policy, access model or downgrade behavior for every order. Treat TLS and SRTP as available service evidence that still requires exact order terms and observed protection on each PBX-facing leg.
Concurrent calls and call starts
Not verifiedThe reviewed pages describe scalable capacity but do not publish one numeric active-call, session, burst or calls-per-second limit. Contracted sessions, simultaneous calls, call starts, PBX channels, access bandwidth and any pooled boundary remain different quantities that require dated account evidence.
Emergency calling
Not verifiedZayo publishes a United States tariff index containing a 911 Emergency Service Advisory for VoIP Services, but the reviewed public SIP pages do not establish the ordered trunk's address workflow, supported countries, accepted caller identity, callback behavior or approved test procedure. Do not infer emergency readiness from US or Canadian service coverage.
Pricing model
Not verifiedThe reviewed public sources promote cost control but do not provide a complete current SIP Solutions rate card. Obtain a dated quote or contract for sessions, minutes, numbers, porting, access, emergency service, protected transport, support, minimums, taxes, renewal, service levels and cancellation.
Administration and support
DocumentedZayo advertises project-managed deployment, administrative visibility, a customer portal for reroutes and billing, and dedicated 24×7 support. Portal state, support availability, loaded PBX configuration, provider acceptance, completed signaling and usable media remain separate evidence.
SMS and MMS
Not verifiedThe reviewed SIP Solutions sources do not establish SMS or MMS entitlement on trunk numbers, API access, sender registration, throughput, webhook security or price. Unified messaging language on separate Zayo Voice or UC+ products must not be transferred to a SIP Solutions order.
Keep SIP Solutions separate from Zayo Voice and UC+
The same portfolio page links SIP Solutions, the separate Zayo Voice hosted phone service and Zayo UC+ with RingCentral. Features, endpoints, messaging, availability statements and administrative workflows on those products do not automatically apply to a SIP trunk that connects a customer-managed PBX.
Identify who owns extensions, dialplan, devices, SBC, numbers, emergency records and call routing. For a Teams or Webex-specific trunk, record the integration owner and approved topology. Do not transfer generic cloud-phone behavior, mobile apps, unified messaging or provider-managed handset support into a PBX-facing trunk comparison.
Translate resilience language into ordered controls
Zayo describes an owned network, geo-redundancy, disaster-recovery options and customer-portal reroutes. It also promotes a 99.999-percent uptime result. Treat that as provider-published service language, not as the exact customer's SLA, observed availability or proof of independent customer access.
Obtain the service-level schedule, primary and alternate ingress points, route order, retryable responses, timers, health signals, restoration procedure and responsibility for a failed customer circuit or SBC. Test only approved new-call failure cases. Keep provider-core redundancy, access diversity, customer-destination failover and survival of an established call as separate acceptance results.
Verify protection on the exact PBX-facing leg
Zayo's current SIP explainer says encrypted SIP services use TLS and SRTP. That establishes published capability but does not define a universal TLS hostname, certificate chain, client-authentication requirement, SRTP keying profile, cipher policy or downgrade behavior for every access model. Private network transport also does not by itself prove application-layer encryption.
For the ordered service, preserve DNS, peer identity, trust store, TLS negotiation, SDP offer and answer, SRTP profile and packet evidence on each leg. A protected Teams or Webex integration does not prove that a separate PBX-facing trunk uses the same policy, and successful SIP setup does not prove encrypted or intelligible media.
Keep capacity, media and fax unresolved until the interface is known
The reviewed public pages describe scalability and quality but do not publish one production interface's codecs, packetization, DTMF, fax mode, concurrent-session limit or calls-per-second control. Those quantities can also vary by access and contract. Do not turn broad HD-voice or capacity language into a codec list or numeric account limit.
Obtain the current interface specification and order. Record purchased sessions, burst policy, call-start rate, PBX resources and access bandwidth separately, then preserve the actual media offer, answer and decoded result. Confirm T.38 or G.711 fax behavior only for the intended gateway, route and page profile.
Validate coverage, emergency service and commercial terms separately
Zayo currently describes SIP Solutions for enterprises across the United States and Canada and says it delivers more than two million numbers. That broad footprint does not establish inventory, portability, number rights or eligibility for a particular location. Use a dated order result for the exact number and market.
The US tariff index links a 911 advisory, but the reviewed public sources do not establish one address-registration, callback or test workflow for every trunk or country. Obtain the applicable emergency terms and provider-approved test process. Confirm messaging as a separate entitlement and use a dated quote for sessions, minutes, numbers, access, protection, support, service levels, taxes, renewal and cancellation. No account, contract, trunk, number, access circuit, PBX, SBC, route, call, media stream, protected session, failover event, emergency workflow, message, price, availability or support response was inspected or tested for this guide.
Sources & applicability
Primary references for the technical details above. Operational examples and planning checklists are VoIP.info editorial guidance.
- Zayo SIP Solutions ↗
- Zayo SIP overview ↗
- Zayo on-net and over-the-top SIP overview ↗
- Zayo SIP trunking explainer ↗
- Zayo United States tariffs and emergency advisory index ↗
Examples require adaptation to your topology. No live PBX or hardware testing is claimed.