SIP BYOC (Bring Your Own Carrier)

---title: SIP BYOC (Bring Your Own Carrier)slug: /guides/sip-byoc-bring-your-own-carriersidebar_position: 2x-custom: ported_from_readme: true---## OverviewBring Your Own Carrier (BYOC) allows SignalWire users to retain their own carriers for connectivity instead of the vendors that we partner with. This allows you to use any carrier you want while still utilizing the **powerful programmatic control** for SIP from SignalWire!This might be a good fit for you if:- You like your current carrier but want to use our APIs to enhance your call flow- You want international origination from a country we dont yet support- The number cannot be ported into SignalWire- You want to keep control of the number rather than port it to SignalWire- You want to SIP trunk to/from a SIP Server (such as Kamailio)## Inbound BYOCIf you would like to do inbound BYOC (i.e. send your carrier traffic to SignalWire), you will need to create a domain application. Domain Apps allow you to send SIP traffic to a custom domain and use SignalWire APIs to manage the incoming request. You can do this under **SIP** -> **Domain Apps** -> **Create a Domain App**, or via the [Domain Apps API](pathname:///rest/create-a-domain-application).

:::caution Whitelisting IPsIts VERY important to whitelist the IPs that you want to allow through - if you do not select this option, anyone who has the URL could send traffic to your custom domain app.:::### Handling Inbound Calls#### Using Compatibility API/XMLIf you try directing traffic to your domain app without configuring it, SignalWire will not pick up the call. To have SignalWire pick up the call, so you can do something with it you will need to:1. Tell the Domain App where to go when a call comes in (by setting the WHEN A CALL COMES IN field);2. Give instructions to SignalWire of what to do with that call.To address both of the steps above, we will need to [create an XML Bin](/guides/creating-and-using-xml-bins). The bare minimum of instructions you must provide for SignalWire to pick up the call is an empty response:xmlThis XML Bin example, with just an empty response, will respond to the call by picking it up. Youll probably want to do much more than this, such as [dialing to another SIP endpoint](pathname:///compatibility-api/xml/voice/sip-noun), so we recommend learning more about the [Verbs you can use](docs/compatibility-api/xml/index.mdx#verbs).Once you have the XML Bin the way you want it, you will need to get its URL and paste it in our Domain Apps WHEN A CALL COMES IN field:

#### Using RelayTo handle incoming calls using a Relay Application, you will need to:1. Give it a context (think of it as a traffic label) to send calls to. Lets use an office context as an example;2. Run code listening for calls on that office context and then do something with them.javascriptimport { Voice } from @signalwire/realtime-api;const client = new Voice.Client({ project: , token: , contexts: [office],});client.on(call.received, async (call) => { console.log(Got call, call.from, call.to); try { await call.answer(); console.log(Inbound call answered); await call.playTTS({ text: Hello! This is a test call. }); } catch (error) { console.error(Error answering inbound call, error); }});In this example were creating a Client and tying it to the office context. Then, we tell it to listen for call.received events, and when a new call comes in we answer it and say Hello! This is a test call. to the caller.To learn more about what you can do with Relay, have a look at our [Relay Realtime SDK documentation](/sdks/reference/realtime-sdk).## Outbound BYOCIf you are using BYOC to do outbound calls from SignalWire, you will need a SIP URL from your carrier that we can use to route calls to the right SIP trunk. Once you have that, you can [create a call using the Compatibility API](pathname:///compatibility-api/rest/create-a-call) or [Relay](https://docs.signalwire.com/reference/relay-sdk-nodejs/v2/#api-reference-relay-calling-methods-dial) using the SIP URL, SIP username, and SIP password. Lets look at some examples so you can see what were talking about!### Outbound Call Examples#### Using Compatibility API/XML##### XML BinsTo start an outbound call using XML Bins you can use the [Dial verb](pathname:///compatibility-api/xml/voice/dial) along with the [SIP noun](pathname:///compatibility-api/xml/voice/sip-noun):xml sip:user@domain.com;transport=udp?header1=foo&header2=bar ##### cURLTo create an outbound call that executes the instructions from a XML Bin we can use the following format for a cURL command:curlcurl https://.signalwire.com/api/laml/2010-04-01/Accounts//Calls.json \ -X POST \ --data-urlencode Url=YourXMLBinURL \ --data-urlencode sip:YOUR SIP URL \ --data-urlencode From=+15550011222 \ --data-urlencode SipAuthUsername=user \ --data-urlencode SipAuthPassword=pass \ -u YourProjectID:YourAuthToken#### Using Relay##### RELAY Realtime SDK[RELAY Realtime SDK](/sdks/reference/realtime-sdk/voice/) is our must recent version of RELAY, and dialing out to a SIP endpoint is simpler than ever:javascriptimport { Voice } from @signalwire/realtime-api;const client = new Voice.Client({ project: , token: , contexts: [office],});try { const call = await client.dialSip({ from: sip:xxx@yyy.zz, to: sip:ppp@qqq.rr, timeout: 30, }); // TODO: Add code to do something with the call object here} catch (e) { console.log(Call not answered.);}##### RELAY SDK (previous version)RELAY SDK is our previous version of RELAY, and is now deprecated, but still supported. Calling out to a SIP endpoint is very similar to the implementation using the latest version:javascriptconst { RelayClient } = require(@signalwire/node);const client = new RelayClient({ project: , token: ,});client.on(signalwire.ready, async (client) => { const dialResult = await client.calling.dial({ type: sip, from: sip:xxx@yyy.zz, to: sip:ppp@qqq.rr, timeout: 30, }); if (dialResult.successful) { const { call } = dialResult; // TODO: Add code to do something with the call object }});client.connect();:::info Dont feel like using JavaScript?Have a look at our [SDKs Technical Reference](/sdks) portal to find .NET, GO, PHP, Ruby, and Python versions of Relay SDK (previous version).:::## How to Get StartedIf you are interested in BYOC, reach out to sales@signalwire.com to get started! One of our Account Executives can make sure everything gets squared away so you can get up and running in no time.Check out our guide on [how to integrate with Thinq as your carrier](/guides/bring-your-own-carrier-byoc-thinq)!## Sign Up HereIf you would like to test this example out, you can create a SignalWire account and space [here](https://m.signalwire.com/signups/new?s=1).Please feel free to reach out to us on our [Community Slack](http://signalwire.community/) or create a Support ticket if you need guidance!