NiceAgent

## NiceAgent NiceAgent — ICE agent API implementation |

## Stability Level

Stable, unless otherwise indicated

## Synopsis

    #include <agent.h>

                        NiceAgent;
    enum                NiceComponentState;
    enum                NiceComponentType;
    enum                NiceProxyType;
    enum                NiceCompatibility;
    void                (*NiceAgentRecvFunc)                (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             guint len,
                                                             gchar *buf,
                                                             gpointer user_data);
    #define             NICE_AGENT_MAX_REMOTE_CANDIDATES
    NiceAgent *         nice_agent_new                      (GMainContext *ctx,
                                                             NiceCompatibility compat);
    NiceAgent *         nice_agent_new_reliable             (GMainContext *ctx,
                                                             NiceCompatibility compat);
    gboolean            nice_agent_add_local_address        (NiceAgent *agent,
                                                             NiceAddress *addr);
    guint               nice_agent_add_stream               (NiceAgent *agent,
                                                             guint n_components);
    void                nice_agent_remove_stream            (NiceAgent *agent,
                                                             guint stream_id);
    gboolean            nice_agent_set_relay_info           (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const gchar *server_ip,
                                                             guint server_port,
                                                             const gchar *username,
                                                             const gchar *password,
                                                             NiceRelayType type);
    gboolean            nice_agent_gather_candidates        (NiceAgent *agent,
                                                             guint stream_id);
    gboolean            nice_agent_set_remote_credentials   (NiceAgent *agent,
                                                             guint stream_id,
                                                             const gchar *ufrag,
                                                             const gchar *pwd);
    gboolean            nice_agent_get_local_credentials    (NiceAgent *agent,
                                                             guint stream_id,
                                                             gchar **ufrag,
                                                             gchar **pwd);
    int                 nice_agent_set_remote_candidates    (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const GSList *candidates);
    GSList *            nice_agent_get_remote_candidates    (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id);
    GSList *            nice_agent_get_local_candidates     (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id);
    gint                nice_agent_send                     (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             guint len,
                                                             const gchar *buf);
    gboolean            nice_agent_attach_recv              (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             GMainContext *ctx,
                                                             NiceAgentRecvFunc func,
                                                             gpointer data);
    gboolean            nice_agent_set_selected_pair        (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const gchar *lfoundation,
                                                             const gchar *rfoundation);
    gboolean            nice_agent_set_selected_remote_candidate
                                                            (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             NiceCandidate *candidate);
    void                nice_agent_set_stream_tos           (NiceAgent *agent,
                                                             guint stream_id,
                                                             gint tos);
    void                nice_agent_set_software             (NiceAgent *agent,
                                                             const gchar *software);
    gboolean            nice_agent_restart                  (NiceAgent *agent);

## Object Hierarchy

      GObject
       +----NiceAgent

## Properties

      "compatibility"            guint                 : Read / Write / Construct Only
      "controlling-mode"         gboolean              : Read / Write
      "full-mode"                gboolean              : Read / Write / Construct Only
      "main-context"             gpointer              : Read / Write / Construct Only
      "max-connectivity-checks"  guint                 : Read / Write
      "proxy-ip"                 gchar*                : Read / Write
      "proxy-password"           gchar*                : Read / Write
      "proxy-port"               guint                 : Read / Write
      "proxy-type"               guint                 : Read / Write
      "proxy-username"           gchar*                : Read / Write
      "reliable"                 gboolean              : Read / Write / Construct Only
      "stun-pacing-timer"        guint                 : Read / Write / Construct Only
      "stun-server"              gchar*                : Read / Write
      "stun-server-port"         guint                 : Read / Write
      "upnp"                     gboolean              : Read / Write / Construct
      "upnp-timeout"             guint                 : Read / Write / Construct

## Signals

      "candidate-gathering-done"                       : Run Last
      "component-state-changed"                        : Run Last
      "initial-binding-request-received"               : Run Last
      "new-candidate"                                  : Run Last
      "new-remote-candidate"                           : Run Last
      "new-selected-pair"                              : Run Last
      "reliable-transport-writable"                    : Run Last

## Description

The NiceAgent is your main object when using libnice. It is the agent that will take care of everything relating to ICE. It will take care of discovering your local candidates and do connectivity checks to create a stream of data between you and your peer.

Example 1. Simple example on how to use libnice

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    guint stream_id;
    gchar buffer[] = "hello world!";
    GSList *lcands = NULL;

    // Create a nice agent
    NiceAgent *agent = nice_agent_new (NULL, NICE_COMPATIBILITY_RFC5245);

    // Connect the signals
    g_signal_connect (G_OBJECT (agent), "candidate-gathering-done",
                      G_CALLBACK (cb_candidate_gathering_done), NULL);
    g_signal_connect (G_OBJECT (agent), "component-state-changed",
                      G_CALLBACK (cb_component_state_changed), NULL);
    g_signal_connect (G_OBJECT (agent), "new-selected-pair",
                      G_CALLBACK (cb_new_selected_pair), NULL);

    // Create a new stream with one component and start gathering candidates
    stream_id = nice_agent_add_stream (agent, 1);
    nice_agent_gather_candidates (agent, stream_id);

    // Attach to the component to receive the data
    nice_agent_attach_recv (agent, stream_id, 1, NULL,
                           cb_nice_recv, NULL);

    // ... Wait until the signal candidate-gathering-done is fired ...
    lcands = nice_agent_get_local_candidates(agent, stream_id, 1);

    // ... Send local candidates to the peer and set the peer's remote candidates
    nice_agent_set_remote_candidates (agent, stream_id, 1, rcands);

    // ... Wait until the signal new-selected-pair is fired ...
    // Send our message!
    nice_agent_send (agent, stream_id, 1, sizeof(buffer), buffer);

    // Anything received will be received through the cb_nice_recv callback

    // Destroy the object
    g_object_unref(agent);

## Details

### NiceAgent

    typedef struct _NiceAgent NiceAgent;

The NiceAgent is the main GObject of the libnice library and represents the ICE agent.

### enum NiceComponentState

    typedef enum
    {
      NICE_COMPONENT_STATE_DISCONNECTED,
      NICE_COMPONENT_STATE_GATHERING,
      NICE_COMPONENT_STATE_CONNECTING,
      NICE_COMPONENT_STATE_CONNECTED,
      NICE_COMPONENT_STATE_READY,
      NICE_COMPONENT_STATE_FAILED,
      NICE_COMPONENT_STATE_LAST
    } NiceComponentState;

An enum representing the state of a component.

See also: "component-state-changed"

`NICE_COMPONENT_STATE_DISCONNECTED` | No activity scheduled
`NICE_COMPONENT_STATE_GATHERING` | Gathering local candidates
`NICE_COMPONENT_STATE_CONNECTING` | Establishing connectivity
`NICE_COMPONENT_STATE_CONNECTED` | At least one working candidate pair
`NICE_COMPONENT_STATE_READY` | ICE concluded, candidate pair selection is now final
`NICE_COMPONENT_STATE_FAILED` | Connectivity checks have been completed, but connectivity was not established
`NICE_COMPONENT_STATE_LAST` | Dummy state

### enum NiceComponentType

    typedef enum
    {
      NICE_COMPONENT_TYPE_RTP = 1,
      NICE_COMPONENT_TYPE_RTCP = 2
    } NiceComponentType;

Convenience enum representing the type of a component for use as the component_id for RTP/RTCP usages.

Example 2. Example of use.

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    nice_agent_send (agent, stream_id, NICE_COMPONENT_TYPE_RTP, len, buf);

`NICE_COMPONENT_TYPE_RTP` | RTP Component type
`NICE_COMPONENT_TYPE_RTCP` | RTCP Component type

### enum NiceProxyType

    typedef enum
    {
      NICE_PROXY_TYPE_NONE = 0,
      NICE_PROXY_TYPE_SOCKS5,
      NICE_PROXY_TYPE_HTTP,
      NICE_PROXY_TYPE_LAST = NICE_PROXY_TYPE_HTTP,
    } NiceProxyType;

An enum to specify which proxy type to use for relaying. Note that the proxies will only be used with TCP TURN relaying.

See also: "proxy-type"

`NICE_PROXY_TYPE_NONE` | Do not use a proxy
`NICE_PROXY_TYPE_SOCKS5` | Use a SOCKS5 proxy
`NICE_PROXY_TYPE_HTTP` | Use an HTTP proxy
`NICE_PROXY_TYPE_LAST` | Dummy last proxy type

Since 0.0.4

### enum NiceCompatibility

    typedef enum
    {
      NICE_COMPATIBILITY_RFC5245 = 0,
      NICE_COMPATIBILITY_GOOGLE,
      NICE_COMPATIBILITY_MSN,
      NICE_COMPATIBILITY_WLM2009,
      NICE_COMPATIBILITY_DRAFT19 = NICE_COMPATIBILITY_RFC5245,
      NICE_COMPATIBILITY_LAST = NICE_COMPATIBILITY_WLM2009,
    } NiceCompatibility;

An enum to specify which compatible specifications the NiceAgent should use. Use with `nice_agent_new()`

### Warning

`NICE_COMPATIBILITY_DRAFT19` is deprecated and should not be used in newly-written code. It is kept for compatibility reasons and represents the same compatibility as `NICE_COMPATIBILITY_RFC5245`

`NICE_COMPATIBILITY_RFC5245` | Use compatibility with the RFC5245 ICE specs
`NICE_COMPATIBILITY_GOOGLE` | Use compatibility for Google Talk specs
`NICE_COMPATIBILITY_MSN` | Use compatibility for MSN Messenger specs
`NICE_COMPATIBILITY_WLM2009` | Use compatibility with Windows Live Messenger 2009
`NICE_COMPATIBILITY_DRAFT19` | Use compatibility for ICE Draft 19 specs
`NICE_COMPATIBILITY_LAST` | Dummy last compatibility mode

### NiceAgentRecvFunc ()

    void                (*NiceAgentRecvFunc)                (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             guint len,
                                                             gchar *buf,
                                                             gpointer user_data);

Callback function when data is received on a component

`agent` : | The NiceAgent Object
`stream_id` : | The id of the stream
`component_id` : | The id of the component of the stream which received the data
`len` : | The length of the data
`buf` : | The buffer containing the data received
`user_data` : | The user data set in `nice_agent_attach_recv()`

### NICE_AGENT_MAX_REMOTE_CANDIDATES

    #define NICE_AGENT_MAX_REMOTE_CANDIDATES    25

A hard limit for the number of remote candidates. This limit is enforced to protect against malevolent remote clients.

### nice_agent_new ()

    NiceAgent *         nice_agent_new                      (GMainContext *ctx,
                                                             NiceCompatibility compat);

Create a new NiceAgent. The returned object must be freed with `g_object_unref()`

`ctx` : | The Glib Mainloop Context to use for timers
`compat` : | The compatibility mode of the agent
Returns : | The new agent GObject

### nice_agent_new_reliable ()

    NiceAgent *         nice_agent_new_reliable             (GMainContext *ctx,
                                                             NiceCompatibility compat);

Create a new NiceAgent in reliable mode, which uses PseudoTcpSocket to assure reliability of the messages. The returned object must be freed with `g_object_unref()`

See also: "reliable-transport-writable"

`ctx` : | The Glib Mainloop Context to use for timers
`compat` : | The compatibility mode of the agent
Returns : | The new agent GObject

Since 0.0.11

### nice_agent_add_local_address ()

    gboolean            nice_agent_add_local_address        (NiceAgent *agent,
                                                             NiceAddress *addr);

Add a local address from which to derive local host candidates for candidate gathering.

Since 0.0.5, if this method is not called, libnice will automatically discover the local addresses available

See also: `nice_agent_gather_candidates()`

`agent` : | The NiceAgent Object
`addr` : | The address to listen to If the port is 0, then a random port will be chosen by the system
Returns : | `TRUE` on success, `FALSE` on fatal (memory allocation) errors

### nice_agent_add_stream ()

    guint               nice_agent_add_stream               (NiceAgent *agent,
                                                             guint n_components);

Adds a data stream to `agent` containing `n_components` components.

`agent` : | The NiceAgent Object
`n_components` : | The number of components to add to the stream
Returns : | The ID of the new stream, 0 on failure

### nice_agent_remove_stream ()

    void                nice_agent_remove_stream            (NiceAgent *agent,
                                                             guint stream_id);

Remove and free a previously created data stream from `agent`

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream to remove

### nice_agent_set_relay_info ()

    gboolean            nice_agent_set_relay_info           (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const gchar *server_ip,
                                                             guint server_port,
                                                             const gchar *username,
                                                             const gchar *password,
                                                             NiceRelayType type);

Sets the settings for using a relay server during the candidate discovery.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`server_ip` : | The IP address of the TURN server
`server_port` : | The port of the TURN server
`username` : | The TURN username to use for the allocate
`password` : | The TURN password to use for the allocate
`type` : | The type of relay to use
Returns : | `TRUE` if the TURN settings were accepted. `FALSE` if the address was invalid.

### nice_agent_gather_candidates ()

    gboolean            nice_agent_gather_candidates        (NiceAgent *agent,
                                                             guint stream_id);

Start the candidate gathering process. Once done, "candidate-gathering-done" is called for the stream

`agent` : | The NiceAgent Object
`stream_id` : | The id of the stream to start
Returns : | `FALSE` if there were no local addresses and they couldn't be discovered. In this case, call `nice_agent_add_local_address()` first. See also: `nice_agent_add_local_address()` ### Note Local addresses can be previously set with `nice_agent_add_local_address()` Since 0.0.5, If no local address was previously added, then the nice agent will automatically detect the local address using `nice_interfaces_get_local_ips()`

### nice_agent_set_remote_credentials ()

    gboolean            nice_agent_set_remote_credentials   (NiceAgent *agent,
                                                             guint stream_id,
                                                             const gchar *ufrag,
                                                             const gchar *pwd);

Sets the remote credentials for stream `stream_id`.

### Note

Stream credentials do not override per-candidate credentials if set

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`ufrag` : | NULL-terminated string containing an ICE username fragment (length must be between 22 and 256 chars)
`pwd` : | NULL-terminated string containing an ICE password (length must be between 4 and 256 chars)
Returns : | `TRUE` on success, `FALSE` on error.

### nice_agent_get_local_credentials ()

    gboolean            nice_agent_get_local_credentials    (NiceAgent *agent,
                                                             guint stream_id,
                                                             gchar **ufrag,
                                                             gchar **pwd);

Gets the local credentials for stream `stream_id`.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`ufrag` : | a pointer to a NULL-terminated string containing an ICE username fragment [OUT]. This string must be freed with `g_free()`
`pwd` : | a pointer to a NULL-terminated string containing an ICE password [OUT] This string must be freed with `g_free()`
Returns : | `TRUE` on success, `FALSE` on error.

### nice_agent_set_remote_candidates ()

    int                 nice_agent_set_remote_candidates    (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const GSList *candidates);

Sets, adds or updates the remote candidates for a component of a stream.

### Note

NICE_AGENT_MAX_REMOTE_CANDIDATES is the absolute maximum limit for remote candidates.

You must first call `nice_agent_gather_candidates()` and wait for the "candidate-gathering-done" signale before calling `nice_agent_set_remote_candidates()`

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream the candidates are for
`component_id` : | The ID of the component the candidates are for
`candidates` : | a GList of NiceCandidate items describing each candidate to add
Returns : | The number of candidates added, negative on errors (memory allocation or if the local candidates are not done gathering yet)

### nice_agent_get_remote_candidates ()

    GSList *            nice_agent_get_remote_candidates    (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id);

Get a list of the remote candidates set on a stream's component

### Note

The caller owns the returned GSList but not the candidates contained within it.

The list of remote candidates can change during processing. The client should register for the "new-remote-candidate" signal to get notified of new remote candidates.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
Returns : | a GSList of NiceCandidates objects representing the remote candidates set on the `agent`

### nice_agent_get_local_candidates ()

    GSList *            nice_agent_get_local_candidates     (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id);

Retreive from the agent the list of all local candidates for a stream's component

### Note

The caller owns the returned GSList as well as the candidates contained within it. To get full results, the client should wait for the "candidate-gathering-done" signal.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
Returns : | a GSList of NiceCandidate objects representing the local candidates of `agent`

### nice_agent_send ()

    gint                nice_agent_send                     (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             guint len,
                                                             const gchar *buf);

Sends a data payload over a stream's component.

### Note

Component state MUST be NICE_COMPONENT_STATE_READY, or as a special case, in any state if component was in READY state before and was then restarted

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream to send to
`component_id` : | The ID of the component to send to
`len` : | The length of the buffer to send
`buf` : | The buffer of data to send
Returns : | The number of bytes sent, or negative error code

### nice_agent_attach_recv ()

    gboolean            nice_agent_attach_recv              (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             GMainContext *ctx,
                                                             NiceAgentRecvFunc func,
                                                             gpointer data);

Attaches the stream's component's sockets to the Glib Mainloop Context in order to be notified whenever data becomes available for a component.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of stream
`component_id` : | The ID of the component
`ctx` : | The Glib Mainloop Context to use for listening on the component
`func` : | The callback function to be called when data is received on the stream's component
`data` : | user data associated with the callback
Returns : | `TRUE` on success, `FALSE` if the stream or component IDs are invalid.

### nice_agent_set_selected_pair ()

    gboolean            nice_agent_set_selected_pair        (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             const gchar *lfoundation,
                                                             const gchar *rfoundation);

Sets the selected candidate pair for media transmission for a given stream's component. Calling this function will disable all further ICE processing (connection check, state machine updates, etc). Note that keepalives will continue to be sent.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`lfoundation` : | The local foundation of the candidate to use
`rfoundation` : | The remote foundation of the candidate to use
Returns : | `TRUE` on success, `FALSE` if the candidate pair cannot be found

### nice_agent_set_selected_remote_candidate ()

    gboolean            nice_agent_set_selected_remote_candidate
                                                            (NiceAgent *agent,
                                                             guint stream_id,
                                                             guint component_id,
                                                             NiceCandidate *candidate);

Sets the selected remote candidate for media transmission for a given stream's component. This is used to force the selection of a specific remote candidate even when connectivity checks are failing (e.g. non-ICE compatible candidates). Calling this function will disable all further ICE processing (connection check, state machine updates, etc). Note that keepalives will continue to be sent.

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`candidate` : | The NiceCandidate to select
Returns : | `TRUE` on success, `FALSE` on failure

### nice_agent_set_stream_tos ()

    void                nice_agent_set_stream_tos           (NiceAgent *agent,
                                                             guint stream_id,
                                                             gint tos);

Sets the IP_TOS and/or IPV6_TCLASS field on the stream's sockets' options

`agent` : | The NiceAgent Object
`stream_id` : | The ID of the stream
`tos` : | The ToS to set

Since 0.0.9

### nice_agent_set_software ()

    void                nice_agent_set_software             (NiceAgent *agent,
                                                             const gchar *software);

This function will set the value of the SOFTWARE attribute to be added to STUN requests, responses and error responses sent during connectivity checks.

The SOFTWARE attribute will only be added in the NICE_COMPATIBILITY_RFC5245 and NICE_COMPATIBILITY_WLM2009 compatibility modes.

### Note

The `software` argument will be appended with the libnice version before being sent.

The `software` argument must be in UTF-8 encoding and only the first 128 characters will be sent.

`agent` : | The NiceAgent Object
`software` : | The value of the SOFTWARE attribute to add.

Since 0.0.10

### nice_agent_restart ()

    gboolean            nice_agent_restart                  (NiceAgent *agent);

Restarts the session as defined in ICE draft 19. This function needs to be called both when initiating (ICE spec section 9.1.1.1. "ICE Restarts"), as well as when reacting (spec section 9.2.1.1. "Detecting ICE Restart") to a restart.

`agent` : | The NiceAgent Object
Returns : | `TRUE` on success `FALSE` on error

## Property Details

### The `"compatibility"` property

      "compatibility"            guint                 : Read / Write / Construct Only

The Nice agent can work in various compatibility modes depending on what the application/peer needs.

See also: NiceCompatibility

Allowed values: <= 3

Default value: 0

### The `"controlling-mode"` property

      "controlling-mode"         gboolean              : Read / Write

Whether the agent is in controlling mode.

Default value: FALSE

### The `"full-mode"` property

      "full-mode"                gboolean              : Read / Write / Construct Only

Whether agent runs in ICE full mode.

Default value: TRUE

### The `"main-context"` property

      "main-context"             gpointer              : Read / Write / Construct Only

A GLib main context is needed for all timeouts used by libnice. This is a property being set by the `nice_agent_new()` call.

### The `"max-connectivity-checks"` property

      "max-connectivity-checks"  guint                 : Read / Write

Upper limit for the total number of connectivity checks performed.

Default value: 0

### The `"proxy-ip"` property

      "proxy-ip"                 gchar*                : Read / Write

The proxy server IP used to bypass a proxy firewall

Default value: NULL

Since 0.0.4

### The `"proxy-password"` property

      "proxy-password"           gchar*                : Read / Write

The password used to authenticate with the proxy

Default value: NULL

Since 0.0.4

### The `"proxy-port"` property

      "proxy-port"               guint                 : Read / Write

The proxy server port used to bypass a proxy firewall

Allowed values: [1,65536]

Default value: 1

Since 0.0.4

### The `"proxy-type"` property

      "proxy-type"               guint                 : Read / Write

The type of proxy set in the proxy-ip property

Allowed values: <= 2

Default value: 0

Since 0.0.4

### The `"proxy-username"` property

      "proxy-username"           gchar*                : Read / Write

The username used to authenticate with the proxy

Default value: NULL

Since 0.0.4

### The `"reliable"` property

      "reliable"                 gboolean              : Read / Write / Construct Only

Whether the agent should use PseudoTcp to ensure a reliable transport of messages

Default value: FALSE

Since 0.0.11

### The `"stun-pacing-timer"` property

      "stun-pacing-timer"        guint                 : Read / Write / Construct Only

Timer 'Ta' (msecs) used in the IETF ICE specification for pacing candidate gathering and sending of connectivity checks.

Allowed values: >= 1

Default value: 20

### The `"stun-server"` property

      "stun-server"              gchar*                : Read / Write

The STUN server used to obtain server-reflexive candidates.

Default value: NULL

### The `"stun-server-port"` property

      "stun-server-port"         guint                 : Read / Write

The STUN server used to obtain server-reflexive candidates.

Allowed values: [1,65536]

Default value: 1

### The `"upnp"` property

      "upnp"                     gboolean              : Read / Write / Construct

Whether the agent should use UPnP to open a port in the router and get the external IP

Default value: TRUE

Since 0.0.7

### The `"upnp-timeout"` property

      "upnp-timeout"             guint                 : Read / Write / Construct

The maximum amount of time to wait for UPnP discovery to finish before signaling the "candidate-gathering-done" signal

Allowed values: [100,60000]

Default value: 200

Since 0.0.7

## Signal Details

### The `"candidate-gathering-done"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            gpointer   user_data)      : Run Last

This signal is fired whenever a stream has finished gathering its candidates after a call to `nice_agent_gather_candidates()`

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`user_data` : | user data set when the signal handler was connected.

### The `"component-state-changed"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            guint      component_id,
                                                            guint      state,
                                                            gpointer   user_data)         : Run Last

This signal is fired whenever a component's state changes

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`state` : | The NiceComponentState of the component
`user_data` : | user data set when the signal handler was connected.

### The `"initial-binding-request-received"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            gpointer   user_data)      : Run Last

This signal is fired when we received our first binding request from the peer.

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`user_data` : | user data set when the signal handler was connected.

### The `"new-candidate"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            guint      component_id,
                                                            gchar     *foundation,
                                                            gpointer   user_data)         : Run Last

This signal is fired when the agent discovers a new candidate

See also: "candidate-gathering-done"

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`foundation` : | The foundation of the new candidate
`user_data` : | user data set when the signal handler was connected.

### The `"new-remote-candidate"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            guint      component_id,
                                                            gchar     *foundation,
                                                            gpointer   user_data)         : Run Last

This signal is fired when the agent discovers a new remote candidate. This can happen with peer reflexive candidates.

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`foundation` : | The foundation of the new candidate
`user_data` : | user data set when the signal handler was connected.

### The `"new-selected-pair"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            guint      component_id,
                                                            gchar     *lfoundation,
                                                            gchar     *rfoundation,
                                                            gpointer   user_data)         : Run Last

This signal is fired once a candidate pair is selected for data transfer for a stream's component

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`lfoundation` : | The local foundation of the selected candidate pair
`rfoundation` : | The remote foundation of the selected candidate pair
`user_data` : | user data set when the signal handler was connected.

### The `"reliable-transport-writable"` signal

    void                user_function                      (NiceAgent *agent,
                                                            guint      stream_id,
                                                            guint      component_id,
                                                            gpointer   user_data)         : Run Last

This signal is fired on the reliable NiceAgent when the underlying reliable transport becomes writable. This signal is only emitted when the `nice_agent_send()` function returns less bytes than requested to send (or -1) and once when the connection is established.

`agent` : | The NiceAgent object
`stream_id` : | The ID of the stream
`component_id` : | The ID of the component
`user_data` : | user data set when the signal handler was connected.

Since 0.0.11

## See Also

NiceAddress