---
title: Connect an AudioCodes Mediant SBC to TelecomsXchange
url: https://help.telecomsxchange.com/integrations/audiocodes-sbc/
audience: Integrations
summary: On the Mediant SBC, add a Proxy Set with sip01.telecomsxchange.com:5060 over
  UDP and Proxy Keep-Alive disabled, a Server-type IP Group for TelecomsXchange, an
  IP-to-IP routing rule to it, and an outbound manipulation that adds the tech prefix
  (80039#) to the destination URI. Authorise the SBC's public IP on the account, or
  add an Account with the VoIP login and Register set to No. Classify calls from 174.136.44.213
  to the same IP Group.
updated: '2026-10-23'
verified_commit: 83b4ebc96d0081a25213776d5a8871bd04941125
---

# Connect an AudioCodes Mediant SBC to TelecomsXchange

> On the Mediant SBC, add a Proxy Set with sip01.telecomsxchange.com:5060 over UDP and Proxy Keep-Alive disabled, a Server-type IP Group for TelecomsXchange, an IP-to-IP routing rule to it, and an outbound manipulation that adds the tech prefix (80039#) to the destination URI. Authorise the SBC's public IP on the account, or add an Account with the VoIP login and Register set to No. Classify calls from 174.136.44.213 to the same IP Group.

## Your SBC to a purchased route

1. **PBX, Teams or Zoom**: Behind your Mediant SBC
2. **AudioCodes SBC**: IP Group TCXC, UDP, prefix added
3. **TelecomsXchange** (via `80039#447700900123`): sip01, UDP 5060
4. **Seller's route**: The route you purchased

An AudioCodes Mediant SBC (Mediant 500 to 9000, and Mediant VE or Software SBC) connects to TelecomsXchange as a SIP peer: one **Proxy Set** and **IP Group** for TelecomsXchange, routing rules in each direction, and a manipulation for the tech prefix. The steps use the Web interface of firmware 7.4 and later; the same tables exist in the CLI and INI file. 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, and it supports SIP over **UDP only**, with RTP (no TLS or SRTP). Use UDP on the TelecomsXchange leg, don't enable registration toward it, and leave **Proxy Keep-Alive** disabled. The SBC 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 the SBC's public WAN 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**.
- The SBC's WAN IP interface, a Media Realm for it, and a working connection to your PBX, Teams or Zoom on the other side.
- To sell: a [route](https://help.telecomsxchange.com/sellers/add-your-first-route/) with **IP Address:Port** set to the SBC, 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?

All tables are under **Setup → Signaling & Media**.

1. **SIP Interface** (**Core Entities → SIP Interfaces**): use or add an interface on the WAN network interface with **UDP Port** `5060` and **Application Type** **SBC**, for example `WAN-UDP`. Give it the WAN **Media Realm**.
2. **Proxy Set** (**Core Entities → Proxy Sets**): add one named `TCXC`:
    - **SBC IPv4 SIP Interface**: `WAN-UDP`.
    - **Proxy Keep-Alive**: **Disable**. TelecomsXchange answers OPTIONS only within a call.
    - In its **Proxy Address** child table, add `sip01.telecomsxchange.com:5060` with **Transport Type** **UDP**. It resolves to `174.136.44.213`.
3. **IP Group** (**Core Entities → IP Groups**): add one named `TCXC`:
    - **Type**: **Server**.
    - **Proxy Set**: `TCXC`. **Media Realm**: the WAN realm.
    - **IP Profile**: a profile with the codecs the route supports (G.729, G.711) and no SRTP (**SBC Media Security Mode** **Not Secured**).
    - **Classify By Proxy Set**: **Enable** is fine when only this IP Group uses `174.136.44.213`; otherwise use the Classification table below.
4. **Routing** (**SBC → Routing → IP-to-IP Routing**): add a rule from your PBX, Teams or Zoom IP Group, matching the destinations the route covers (for example **Destination Username Pattern** `44`), with **Destination Type** **IP Group** and **Destination IP Group** `TCXC`.
5. **Tech prefix** (**SBC → Manipulation → Outbound Manipulations**): add a rule:

| Field | Value |
|---|---|
| Name | `TCXC tech prefix` |
| Destination IP Group | `TCXC` |
| Destination Username Pattern | `*` |
| Request Type | **INVITE** |
| Manipulated Item | **Destination URI** |
| Remove From Left | `0` (or `2` to strip a leading `00`) |
| Prefix to Add | `80039#` |

The Request-URI leaves the SBC as `sip:80039#447700900123@sip01.telecomsxchange.com`. Numbers must reach this rule in E.164 without `+` or `00`; strip `+` with an inbound manipulation on the source IP Group (for Teams, numbers arrive as `+447700900123`).

**Digest variant.** If the SBC sends from an IP that isn't on the account, add an Account (**SIP Definitions → Accounts**):

| Field | Value |
|---|---|
| Served IP Group | your PBX, Teams or Zoom IP Group |
| Serving IP Group | `TCXC` |
| User Name | `VOIP_LOGIN` |
| Password | `VOIP_PASSWORD` |
| Register | **No** |

With **Register: No**, the SBC doesn't register; it answers TelecomsXchange's 401 or 407 challenge on the INVITE with these credentials.

!!! tip
    For several routes, add one Outbound Manipulation per tech prefix, each matching its destinations with **Destination Username Pattern**, or dial a [routing group](https://help.telecomsxchange.com/buyers/routing-groups-and-route-testing/) prefix such as `444101#` and let TelecomsXchange choose.

## How do I receive calls from TelecomsXchange?

Calls on routes you sell, and on numbers you bought, 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 UDP 5060 and the WAN Media Realm's port range. On the SBC, a **Firewall** (access list) rule can restrict SIP on the WAN interface to it.
2. **Classification** (**SBC → Classification Table**): unless **Classify By Proxy Set** is on, add a rule with **Source SIP Interface** `WAN-UDP`, **Source IP Address** `174.136.44.213`, **Action Type** **Allow** and **Source IP Group** `TCXC`. Calls from other addresses on that interface fall through to your other rules or are rejected.
3. **Routing** (**SBC → Routing → IP-to-IP Routing**): add a rule with **Source IP Group** `TCXC` to the IP Group of your PBX, carrier, Teams or Zoom. Route by **Destination Username Pattern** if different numbers go to different places.
4. Teams expects numbers in `+E.164`; add `+` with an outbound manipulation toward the Teams IP Group (**Prefix to Add** `+`).
5. If your TelecomsXchange route adds an **Outgoing Prefix** (**Edit Route → Outgoing Number Translation Parameters**), remove it with an **Inbound Manipulation** on IP Group `TCXC` (**Remove From Left**).

## How do I receive calls on numbers I bought?

Set the number's **SIP Endpoint (Primary)** in **DID Settings** on TelecomsXchange to the SBC, for example `sip:14165551234@203.0.113.10:5060`. The call is classified into IP Group `TCXC` and routed by the IP-to-IP rule above to the PBX, Teams user or Zoom user that owns the number.

## How do I use it with Microsoft Teams or Zoom Phone?

Microsoft Teams Direct Routing and Zoom Phone BYOC (Bring Your Own Carrier) only connect to a certified SBC over SIP TLS with SRTP. TelecomsXchange doesn't offer TLS or SRTP, so it can't be the TLS endpoint for Teams or Zoom. The Mediant SBC sits in between:

- **Teams or Zoom side**: TLS on port 5061, SRTP, a certificate for your SBC's FQDN, and the vendor's own IP Group and IP Profile, as in AudioCodes' configuration notes.
- **TelecomsXchange side**: the UDP Proxy Set and IP Group in this guide, with RTP. The SBC converts SRTP to RTP between the two IP Profiles.

See [Connect Microsoft Teams](https://help.telecomsxchange.com/integrations/microsoft-teams/) and [Connect Zoom Phone](https://help.telecomsxchange.com/integrations/zoom-phone/) for the Teams and Zoom side.

## How do I test it?

1. Send the SBC's syslog to the **Syslog Viewer** (or open the Web interface's **Message Log** under **Troubleshoot**) and enable SIP debug; or start a **Debug Recording** and open it in Wireshark.
2. Place a call to a number covered by the route.
3. In the log, look for the INVITE to `80039#447700900123` toward `174.136.44.213` and the reply. The **Monitor** tab's active calls view shows calls in progress.
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 repeated, then the call fails | The SBC isn't answering the challenge. Add the Account with **Serving IP Group** `TCXC`, **Register: No**, and the VoIP login and password from **Edit Account**. |
| 403 Forbidden | The SBC's public IP isn't authorised and no credentials were sent, or the account is blocked or out of balance. Behind NAT, authorise the public address. |
| 404 Not Found | Missing or wrong tech prefix, or `+`/`00` left in the number. Check the Outbound Manipulation and the Request-URI in the log. |
| 408 Request Timeout | No reply from sip01. Check the Proxy Address, **Transport Type: UDP**, DNS on the SBC, and outbound UDP 5060. |
| Proxy Set shown as down, calls not routed | **Proxy Keep-Alive** is on. Set it to **Disable**. |
| 503 Service Unavailable | The route is blocked or failed on the seller's side. Check **My Interconnections**; add an alternative routing rule. |
| One-way or no audio | The WAN Media Realm advertises a private IP, or RTP is blocked. Set the NAT translation for the WAN interface and open the media port range. On Teams or Zoom calls, check the SRTP-to-RTP IP Profiles. |
| Inbound calls rejected | No classification matches `174.136.44.213`, or the call has no IP-to-IP route from `TCXC`. Check the Classification Table and the firewall. |

## References

- [AudioCodes: Configuring Proxy Sets](https://techdocs.audiocodes.com/session-border-controller-sbc/mediant-2600-sbc/user-manual/version-740/Content/UM/Configuring%20Proxy%20Sets.htm)
- [AudioCodes: Configuring Classification Rules](https://techdocs.audiocodes.com/session-border-controller-sbc/mediant-2600-sbc/user-manual/version-740/Content/UM/Configuring%20Classification%20Rules.htm)
- [AudioCodes: Configuring SBC IP-to-IP Routing Rules](https://techdocs.audiocodes.com/session-border-controller-sbc/mediant-software-sbc/user-manual/version-740/Content/UM/Configuring%20SBC%20IP-to-IP%20Routing.htm)
- [AudioCodes: Configuring IP-to-IP Outbound Manipulations](https://techdocs.audiocodes.com/session-border-controller-sbc/mediant-2600-sbc/user-manual/version-740/Content/UM/Configuring%20IP-to-IP%20Outbound%20Manipulations.htm)
- [AudioCodes: Configuring Registration Accounts](https://techdocs.audiocodes.com/session-border-controller-sbc/mediant-2600-sbc/user-manual/version-740/Content/UM/Configuring%20Registration%20Accounts.htm)

## Frequently asked questions

**Q: Can the AudioCodes SBC register to TelecomsXchange?**

A: No. TelecomsXchange is peering only and does not accept REGISTER. If you add an Account for digest credentials, set Register to No: the SBC then only answers the challenge on INVITEs.

**Q: Where does the tech prefix go?**

A: In an outbound manipulation rule (SBC, Manipulation, Outbound Manipulations) with Destination IP Group TCXC, Manipulated Item Destination URI, and Prefix to Add 80039#.

**Q: Can I connect Microsoft Teams or Zoom Phone to TelecomsXchange through the SBC?**

A: Yes. Teams Direct Routing and Zoom Phone BYOC need TLS and SRTP, which TelecomsXchange doesn't offer. The SBC terminates TLS and SRTP on the Teams or Zoom side and talks to TelecomsXchange over UDP and RTP.

**Q: Should I enable Proxy Keep-Alive?**

A: No. TelecomsXchange answers SIP OPTIONS only within a call, so keep-alive would mark the proxy set down. Leave Proxy Keep-Alive at Disable.