---
title: "proto_bins Module"
description: "This module implements a secure Binary communication protocol over TLS, to be used by the OpenSIPS clustering engine provided by the clusterer module."
---

## Admin Guide


### Overview


This module implements a secure Binary communication protocol
over TLS, to be used by the OpenSIPS clustering engine provided
by the clusterer module.


Once loaded, you will be able to define BINS listeners in your
configuration file by adding their IP and, optionally, a
listening port, similar to this example:

```opensips
...
socket = bins:127.0.0.1 		# change the listening IP
socket = bins:127.0.0.1:5557	# change the listening IP and port
...
```


### Dependencies


#### OpenSIPS Modules


The following modules must be loaded before this module:


- *tls_openssl* or *tls_wolfssl*,
depending on the desired TLS library
- *tls_mgm*.


#### External Libraries or Applications


The following libraries or applications must be installed before
running OpenSIPS with this module loaded:


- *None*.


### Exported Parameters


#### bins_port (integer)


The default port to be used by all BINS listeners.


*Default value is 5556.*


```c title="Set bins_port parameter"
...
modparam("proto_bins", "bins_port", 5557)
...
```


#### bins_handshake_timeout (integer)


Sets the timeout (in milliseconds) for the SSL/TLS handshake
sequence to complete. It may be necessary to increase this
value when using a CPU intensive cipher for the connection to
allow time for keys to be generated and processed.


The timeout is invoked during acceptance of a new connection
(inbound) and during the wait period when a new session is
being initiated (outbound).


*Default value is 100.*


```opensips title="Set bins_handshake_timeout variable"
param("proto_tls", "bins_handshake_timeout", 200) # number of milliseconds			
```


#### bins_send_timeout (integer)


Sets the timeout (in milliseconds) for blocking send operations
to complete.


The send timeout is invoked for all TLS write operations,
excluding the handshake process (see: bins_handshake_timeout)


*Default value is 100 ms.*


```opensips title="Set bins_send_timeout parameter"
...
modparam("proto_bins", "bins_send_timeout", 200)
...
```


#### bins_max_msg_chunks (integer)


The maximum number of chunks in which a BINS message is
expected to arrive via TCP. If a received packet is more
fragmented than this, the connection is dropped (either the
connection is very overloaded and this leads to high
fragmentation - or we are the victim of an ongoing attack where
the attacker is sending very fragmented traffic in order to
decrease server performance).


*Default value is 32.*


```opensips title="Set bins_max_msg_chunks parameter"
...
modparam("proto_bins", "bins_max_msg_chunks", 8)
...
```


#### bins_async (integer)


Specifies whether the TCP/TLS connect and write operations
should be done in an asynchronous mode (non-blocking connect
and write) or not. If disabled, OpenSIPS will block and wait
for TCP/TLS operations like connect and write.


*Default value is 1 (enabled).*


```opensips title="Set bins_async parameter"
...
modparam("proto_bins", "bins_async", 0)
...
```


#### bins_async_max_postponed_chunks (integer)


If bins_async is enabled, this specifies the maximum number of
BINS messages that can be stashed for later/async writing. If
the connection pending writes exceed this number, the
connection will be marked as broken and dropped.


*Default value is 32.*


```opensips title="Set bins_async_max_postponed_chunks parameter"
...
modparam("proto_bins", "bins_async_max_postponed_chunks", 16)
...
```


#### trace_destination (string)


Trace destination as defined in the tracing module. Currently
the only tracing module is **proto_hep**.
Network events such as connect, accept and connection closed events
shall be traced along with errors that could appear in the process.
For each connection that is created an event containing information
about the client and server certificates, master key and network layer
information shall be sent.


> [!WARNING]
> A tracing module must be
> loaded in order for this parameter to work. (for example
> **proto_hep**).


*Default value is none(not defined).*


```opensips title="Set trace_destination parameter"
...
modparam("proto_hep", "hep_id", "[hep_dest]10.0.0.2;transport=tcp;version=3")
modparam("proto_bins", "trace_destination", "hep_dest")
...
```


#### trace_on (int)


This controls whether tracing for tls is on or not. You still need to define
[trace destination](#trace_destination-string)in order to work, but this value will be
controlled using mi function [mi trace](#binstrace).


```opensips title="Set trace_on parameter"
...
modparam("proto_bins", "trace_on", 1)
...
```


### Exported MI Functions


#### bins:trace


Replaces obsolete MI command: *tls_trace*.


Name: *bins:trace*


Parameters:


- trace_mode(optional): set bins tracing on and off. This parameter
can be missing and the command will show the current tracing
status for this module( on or off );
Possible values:
	- on
	- off


MI FIFO Command Format:


```bash
opensips-cli -x mi bins:trace on		
```
<!-- CONTRIBUTORS -->

### License

All documentation files (i.e. .md extension) are licensed under the Creative Common License 4.0
