> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/tmedia-documentation/configuration/web-portal-3-3/protocol-stack/isdn-fas-and-nfas/configuring-an-isdn-stack.md).

# Configuring an ISDN Stack

> **Applies to:** Tmedia 3.0, 3.2, 3.3

Integrated Systems Digital Network (ISDN) is a circuit-switched telephone system that integrates voice and data on the same lines. Tmedia and Tdev systems can be configured to provide an ISDN signaling stack on the trunks of one or more units to meet system configuration requirements. To configure ISDN ,you must first create an ISDN stack.

To create a new ISDN stack:

1- Click **ISDN** in the navigation menu, under the Signaling header

![Create ISDN Stack 0](https://docs.telcobridges.com/w/images/b/b5/Create_ISDN_Stack_0.png)

2- Click **Create New ISDN Stack**

![Create ISDN Stack 1](https://docs.telcobridges.com/w/images/d/d8/Create_ISDN_Stack_1.png)

3- Create the new stack:

* Verify that the box labeled **Enabled** is checked
* Enter a **name** for the new ISDN stack
* Select a **variant** to associate with the stack
* Determine whether the stack will operate on the **user side**, or the **network side**
* Select a **Line Service**
* Click **Create**

![Create ISDN Stack 2 a](https://docs.telcobridges.com/w/images/c/cf/Create_ISDN_Stack_2_a.png)

4- Verify that the **"ISDN stack was successfully created"** message appears, and that the new stack is listed in the **ISDN Stack List**

![Create ISDN Stack 3](https://docs.telcobridges.com/w/images/7/7e/Create_ISDN_Stack_3.png)

**Path**

```
/configurations/@[configuration_name]/hardware_units/@[hardware_name]/isdn_stacks/@[isdn_stack]
```

**Parameters (text)**

```
/configurations/@[configuration_name]/hardware_units/@[hardware_name]/isdn_stacks/@[isdn_stack]
dchannel_bkp_line_service = ""
enabled                   = true
line_services             = [ "@[line_service_name]" ]
name                      = "FNT01"
side                      = "User"
variant                   = "NET5"

/configurations/@[configuration_name]/hardware_units/@[hardware_name]/isdn_stacks/@[isdn_stack]/advanced_parameters
force_wake_up = false
options       = 0

/configurations/@[configuration_name]/hardware_units/@[hardware_name]/isdn_stacks/@[isdn_stack]/timers
t301_timer         = "3 minutes"
t302_timer         = "15 seconds"
t303_timer         = "4 seconds"
t304_timer         = "20 seconds"
t305_timer         = "30 seconds"
t307_timer         = "3 minutes"
t308_timer         = "4 seconds"
t309_net5_timer    = "6 seconds"
t309_timer         = "90 seconds"
t310_network_timer = "10 seconds"
t310_user_timer    = "30 seconds"
t313_timer         = "4 seconds"
t316_timer         = "4 seconds"
```

**Parameters (json)**

```
{
  "advanced_parameters" : {
    "force_wake_up" : false,
    "options" : 0
  },
  "dchannel_bkp_line_service" : "",
  "enabled" : true,
  "line_services" : [
    "@[line_service_name]"
  ],
  "name" : "@[isdn_stack]",
  "side" : "User",
  "timers" : {
    "t301_timer" : "3 minutes",
    "t302_timer" : "15 seconds",
    "t303_timer" : "4 seconds",
    "t304_timer" : "20 seconds",
    "t305_timer" : "30 seconds",
    "t307_timer" : "3 minutes",
    "t308_timer" : "4 seconds",
    "t309_net5_timer" : "6 seconds",
    "t309_timer" : "90 seconds",
    "t310_network_timer" : "10 seconds",
    "t310_user_timer" : "30 seconds",
    "t313_timer" : "4 seconds",
    "t316_timer" : "4 seconds"
  },
  "variant" : "NET5"
}
```

### List of Parameters

* [Enabled](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/sip#e)
* [Name](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/m3ua#n)
* [Variant](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/isdn#i)
* [Side](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/isdn#s)
* [Line Service](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/tdm#l)

**Advanced Parameters**

* [Options](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/isdn#o)
* [Force wake up action](https://prosbcdocs.telcobridges.com/telecom-references/parameter-reference/isdn#f)


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