--- title: Connect VoipSwitch to TelecomsXchange url: https://help.telecomsxchange.com/integrations/voipswitch/ audience: Integrations summary: In VoipSwitch (VSM), add a gateway for sip01.telecomsxchange.com port 5060 over UDP with Ping off, put the tech prefix (80039#) in its Dialed number prefix field, and point a routing plan entry at it. Authorise VoipSwitch's public IP on the TelecomsXchange account, or fill the gateway's User name and User password with the VoIP login. To sell, add a wholesale client with IP 174.136.44.213. updated: '2026-10-23' verified_commit: 83b4ebc96d0081a25213776d5a8871bd04941125 --- # Connect VoipSwitch to TelecomsXchange > In VoipSwitch (VSM), add a gateway for sip01.telecomsxchange.com port 5060 over UDP with Ping off, put the tech prefix (80039#) in its Dialed number prefix field, and point a routing plan entry at it. Authorise VoipSwitch's public IP on the TelecomsXchange account, or fill the gateway's User name and User password with the VoIP login. To sell, add a wholesale client with IP 174.136.44.213. ## VoipSwitch to a purchased route 1. **Your VoipSwitch**: Gateway, Ping off, no registration 2. **TelecomsXchange** (via `80039#447700900123`): sip01, UDP 5060 3. **Seller's route**: The route you purchased VoipSwitch (VoipSwitch Manager, VSM) sends calls to carriers through **gateways** chosen by a **routing plan**, and accepts calls from carriers and resellers as **wholesale clients**. TelecomsXchange is a gateway when you buy routes and a wholesale client when you sell them. For every TelecomsXchange value in one place, see [Connect a SIP platform](https://help.telecomsxchange.com/integrations/connect-sip-platforms/). !!! warning TelecomsXchange does not accept SIP REGISTER. A VoipSwitch gateway doesn't register, so there is nothing to turn off, but don't configure TelecomsXchange as a registration or SIP account anywhere else. VoipSwitch is recognised by its **source IP** or by **digest authentication on the INVITE**. ## Before you start - A [SIP account](https://help.telecomsxchange.com/buyers/create-your-first-account/) on TelecomsXchange with VoipSwitch's public signalling IP, for example `203.0.113.10`, or a VoIP login and password from **Edit Account → Add SIP Digest Auth**. - A [purchased route](https://help.telecomsxchange.com/buyers/find-and-buy-routes/) and its tech prefix from **My Interconnections**, for example `80039#`. In this guide, `TECH_PREFIX` stands for that value, and `VOIP_LOGIN` and `VOIP_PASSWORD` for the account's **VoIP Login** and **VoIP Password**. - Admin access to VSM. - To sell: a [route](https://help.telecomsxchange.com/sellers/add-your-first-route/) with **IP Address:Port** set to VoipSwitch, for example `203.0.113.10:5060`, and the values in [Interconnect Info](https://help.telecomsxchange.com/sellers/interconnect-info/). ## How do I send calls to TelecomsXchange? 1. In VSM, go to **Calls routing → Gateways** and click **Add**. Add one gateway per purchased route. 2. On the **General** tab, set: - **Name**: for example `TCXC 80039 UK`. It is only a label. - **IP number**: `sip01.telecomsxchange.com`. VoipSwitch accepts a domain name here; it resolves to `174.136.44.213`. - **Port**: `5060`. - **Protocol**: **UDP**. - **Ping**: off. TelecomsXchange answers OPTIONS only within a call; with Ping off, the gateway status stays up. - **User name** and **User password**: leave empty for IP authentication, or enter `VOIP_LOGIN` and `VOIP_PASSWORD` for digest authentication. 3. Put the tech prefix in the gateway's **Dialed number prefix** field: `80039#`. VoipSwitch adds it in front of the number, so `447700900123` leaves as `80039#447700900123`. 4. Enable the codecs the route supports (G.729 and G.711 are typical; the Purchased Route Confirmation email lists them). TelecomsXchange passes codecs through and doesn't transcode. 5. Go to **Calls routing → Routing plan** and add an entry for the destinations the route covers, for example prefix `44`, with the TelecomsXchange gateway as its route. Numbers must reach the gateway in E.164 format, without `+` or `00`. If your clients dial `00`, strip it with the client's **Dialing plan prefix** rule `00->`, and copy the same rule to the **Tariff prefix** if your tariffs are in E.164. **Prefix syntax.** VoipSwitch's prefix fields take a small rule language: a plain value such as `80039#` is added in front, `00->` removes a leading `00`, and `00->80039#` replaces `00` with the tech prefix in one step. If a dialing plan rule and a gateway rule both apply, the dialing plan rule wins. !!! tip To let TelecomsXchange pick the route, use a single gateway whose **Dialed number prefix** is a [routing group](https://help.telecomsxchange.com/buyers/routing-groups-and-route-testing/) prefix such as `444101#`. ### How do I bill the cost? On TelecomsXchange, open **Accounts → Edit Account** and download the route's rates from **Purchased Routes** in **Default** format. Import them into a VoipSwitch tariff (**3.2 How to add/import tariff rates**) and set it as the gateway's tariff, so VoipSwitch records your cost per call. ## How do I receive calls from TelecomsXchange? When you sell a route, TelecomsXchange is your customer. Its calls come from `174.136.44.213` over UDP, from source ports 5060 to 5072, with the number in E.164 format such as `14165551234`. 1. Allow `174.136.44.213` on your firewall for SIP (UDP) and your RTP range. 2. In VSM, add a client of the **Wholesale** type, for example `TelecomsXchange`. 3. On its **IP Numbers** tab, add `174.136.44.213`. Wholesale clients are authenticated by IP address, and calls from that IP are billed to this client. 4. Assign the tariff you sell at; every client account needs one, even if you only use it to accept calls. 5. Make sure your routing plan sends the E.164 destinations onward to your own gateways. 6. If your TelecomsXchange route adds an **Outgoing Prefix** (**Edit Route → Outgoing Number Translation Parameters**), strip it with the client's **Dialing plan prefix**, for example `77#->`. !!! warning If you also buy from TelecomsXchange, don't let the wholesale client's calls route back to the TelecomsXchange gateway. Restrict that client's routing so a misrouted call can't loop. ## How do I receive calls on numbers I bought? Set the number's **SIP Endpoint (Primary)** in **DID Settings** on TelecomsXchange to VoipSwitch, for example `sip:14165551234@203.0.113.10:5060`. VoipSwitch authenticates DID sources as wholesale clients, so the same client with IP `174.136.44.213` accepts the call; then assign the number in VoipSwitch's DID settings to the retail client, PBX or IVR that should answer it. ## How do I test it? 1. Place a call from a test client to a number covered by the route. 2. In VSM, check the active calls and the call history for the gateway used, the dialed number sent (`80039#447700900123`) and the result. 3. On the VoipSwitch server, `sngrep port 5060` or Wireshark shows the INVITE and the reply from sip01. 4. On TelecomsXchange, watch the call in **Live Calls** and find its SIP code in **Logs → CDR (Voice)**. ## What if something goes wrong? | You see | What to do | |---|---| | 401 or 407, then the call fails | VoipSwitch's IP isn't authorised and the gateway's **User name** and **User password** are empty or wrong. Enter `VOIP_LOGIN` and `VOIP_PASSWORD` from **Edit Account**. | | 403 Forbidden | VoipSwitch's public IP isn't authorised and no valid credentials were sent, or the account is blocked or out of balance. | | 404 Not Found | Missing or wrong tech prefix, or `00` left in the number. Check the gateway's **Dialed number prefix** and the client's dialing plan rules. | | 408 Request Timeout | No reply from sip01. Check the gateway's **IP number**, **Port** and **Protocol**, and outbound UDP 5060. | | 503 Service Unavailable | The route is blocked or failed on the seller's side. Check **My Interconnections**, and give the routing plan entry a second gateway. | | Gateway shown as down | **Ping** is on. Turn it off for the TelecomsXchange gateway. | | One-way or no audio | VoipSwitch advertises a private IP, or RTP is blocked. Check the media IP in the SDP and open the RTP range. | | Inbound calls rejected | `174.136.44.213` isn't on the wholesale client's **IP Numbers** tab, the client has no tariff, or the firewall blocks it. | ## References - [VoipSwitch: How to add gateway](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/2835513358/4.1+How+to+add+gateway) - [VoipSwitch: How to handle prefix modifications](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/3777036290/How+to+handle+prefix+modifications) - [VoipSwitch: How to route a client call to a specific gateway](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/3759472642/How+to+Route+a+Client+Call+to+a+Specific+Gateway) - [VoipSwitch: Routing plan](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/2262402985/1.4.4+Routing+plan) - [VoipSwitch: Wholesale clients](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/2262401702/1.4.7+Wholesale+clients) - [VoipSwitch: Inbound DIDs flow](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/2262403302/1.7.2+Inbound+DIDs+flow) - [VoipSwitch: How to add/import tariff rates](https://voiceserve.atlassian.net/wiki/spaces/Documentation/pages/2826960897/3.2.+How+to+add+import+tariff+rates) ## Frequently asked questions **Q: Can VoipSwitch register to TelecomsXchange?** A: No. TelecomsXchange is peering only and does not accept REGISTER. A VoipSwitch gateway sends calls without registering; it is recognised by its source IP or answers the digest challenge with the gateway's User name and User password. **Q: Where does the tech prefix go?** A: In the gateway's Dialed number prefix field, for example 80039#. VoipSwitch adds it in front of the number sent to that gateway. Use one gateway per purchased route. **Q: Should I turn on Ping for the gateway?** A: No. TelecomsXchange answers SIP OPTIONS only within a call, so with Ping on the gateway can be marked down. With Ping off, VoipSwitch treats the gateway as up. **Q: How does TelecomsXchange appear when I sell to it?** A: As one wholesale client authenticated by IP 174.136.44.213. Calls arrive in E.164 format such as 14165551234 and are billed with the client's tariff.