> 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/telecom-references/sip-and-voip/software-h-248.md).

# Software:H.248

TelcoBridges [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) stack is inherently highly available since it is part of the [TMG-CONTROL](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/concepts/tctrl/README.md) software.

This means that:

* If the host server fails, application will be restarted (on either primary or secondary host). Calls will remain active.
* If the [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) stack fails, it will be restarted (on either primary or secondary host), and [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) calls will remain active.
* If the TMedia unit fails, the backup unit will takeover (moving TDM trunks and IP interfaces if necessary). [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) terminations will be re-allocated on the backup unit. [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) calls remain active.

TelcoBridges [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) stack, when restarted, will send "919 Warm Failover" event to MGC.

Some MGC, upon reception of "919 Warm Failover", will drop the [H.248](https://github.com/telcobridges-main/tmedia-wiki/tree/main/reference/protocols/h-248-protocol/README.md) calls. TelcoBridges thus offers a "**transparent failover**" option which hides failovers from the MGC, allowing HA behavior even with non-HA aware MGCs. This option is enabled in the Web Portal: H.248 -> Advanced Parameters -> Behavior -> No failover service changes


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://prosbcdocs.telcobridges.com/telecom-references/sip-and-voip/software-h-248.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.