Elastic SIP Trunking

Master your carriers and PBX with zero complexity

bring your own carrier - always

Elastic SIP Trunking connects any SIP-compatible carrier, cloud platform or on-premise equipment to Cloudonix and beyond. Use your existing VoIP providers, phone systems, communications platforms and SIP phones through a simple-to-use SIP connectivity solution.

Unlike other platforms, Cloudonix takes a black-box approach to SIP trunking, hiding the in-depth technical know-how and making the trunking process simple and quick. Got your own PBX? Any vendor or open-source PBX can register to Cloudonix in minutes, keeping your existing call costs intact.

Cloudonix doubles as a painless SBC, with built-in session border controller features such as transcoding and TCP/UDP/TLS negotiation. HD audio is delivered to every call, everywhere, with connectivity in hard-to-reach markets like India and the UAE.

the cloudonix advantage

  • Global Connect with Cloudonix from anywhere in the world. The Cloudonix network spans on all 5 continents.
  • Unlimited Configure an unlimited number of SIP trunks - no minute based charges apply.
  • Agnostic Connect any SIP compliant SIP trunk, with simple "black box" transcoding, audio always connects.

connect in minutes, not days

  1. Get carrier interconnect data — Obtain your carrier SIP interconnect data for either inbound or outbound calling.
  2. Assert geo-requirements — If your carrier is located in India or the UAE, consuilt with Cloudonix staff for interconnecting in these regions.
  3. Configure and Call — Assign your SIP trunk for inbound or outbound calling, and start routing calls.

watch this short tutorial

In this step-by-step guide, you will learn how to configure SIP trunks within the Cloudonix interface and integrate your current telephony infrastructure with Cloudonix.

Video: Managing your Cloudonix account - Platform Fundamentals

schedule a demo with a cloudonix expert

Cloudonix Elastic SIP trunking is the golden standard for interconnecting VoIP systems over the internet, in a secure, private and scalable manner.

Book a meeting (Schedule a Demo, 45 min) on this page.

Frequently asked questions

What is Elastic SIP Trunking on Cloudonix and how does it differ from traditional SIP trunking?

Cloudonix takes a black-box approach to SIP trunking, hiding the in-depth technical complexity and making the trunking process simple and quick. Unlike traditional trunking that requires deep telecom expertise, Cloudonix abstracts the complexities of telecommunications, allowing developers to connect any SIP-compatible carrier, cloud platform, or on-premise equipment in minutes rather than months. It also doubles as a painless SBC with built-in transcoding and TCP/UDP/TLS negotiation. See the Introduction for more on Cloudonix's AI-first communications platform.

Can I use my existing carrier and phone numbers with Cloudonix?

Yes. Cloudonix is BYOC (Bring Your Own Carrier) native — it does not provide phone numbers or call minutes, so you keep your existing carrier relationships and call costs intact. You can connect your current PSTN carrier, SIP trunk provider, or PBX directly to Cloudonix. The Twilio Integration guide explains how both BYOC Trunking and Elastic SIP Trunking work with existing carrier setups.

What SIP-compliant platforms and PBX systems can connect to Cloudonix?

Any SIP-compliant platform can connect, including on-premise PBXs (Asterisk, FreeSWITCH, 3CX, Avaya, Cisco), cloud UCaaS/CCaaS/CPaaS platforms, and open-source SIP projects (OpenSIPS, Kamailio). The Voice Trunk Management page lists verified carriers and vendors with integration ratings, and notes that unlisted providers can still be connected — just contact the team for verification.

How do I configure inbound and outbound trunks in Cloudonix?

You create Inbound Trunks (calls from carrier into Cloudonix) and Outbound Trunks (calls from Cloudonix to carrier) via the developer console or API. Each trunk has properties like transport type (UDP/TCP/TLS), remote address/port, prefix, and authentication. For inbound, Cloudonix auto-generates a domain alias (e.g., 1234567890-abcdefgh.sip.cloudonix.net) that you point your carrier to. Full details are in the Voice Trunk Management documentation.

Does Cloudonix provide phone numbers or call minutes?

No. Cloudonix is a BYOC-native platform — it does not sell phone numbers or call minutes. You bring your own carrier and number inventory, and Cloudonix provides the orchestration layer, SIP connectivity, and AI-first voice services on top. This keeps your existing call costs and carrier contracts unchanged. The Telephony Services overview confirms Cloudonix supports SIP interconnection with any modern telephony provider.

What security and call-quality features does Cloudonix's SIP trunking include?

Cloudonix includes built-in Session Border Controller (SBC) features: transcoding, TCP/UDP/TLS negotiation, and Full INVITE Inspection for security (exact match, partial match, or regex on SIP headers). It delivers HD audio globally and operates in highly regulated markets like India and the UAE. The Cloudonix Advantage page notes this direct-connection approach optimizes costs and ensures call transfers always work.

How quickly can I get a SIP trunk up and running on Cloudonix?

Customers have gotten up and running in as little as 10 minutes, though complex use-cases may take days. Cloudonix recommends starting with the quick-start guides in the developer documentation for a rapid learning experience. The Introduction page emphasizes that Cloudonix lets developers focus on their application — shipping in hours and days, not months.