Connecting cameras via the GB/T28181 protocol

General information on GB/T28181 standard and supported functions

C-Werk supports connecting devices via the Chinese standard GB/T28181. This standard is based on SIP over UDP (and over TCP since GB/T28181-2016). The GB/T28181 uses the following protocols over SIP:

• SDP (Session Description Protocol);
• MANSCDP (Monitoring and Alarming Network System Control Description Protocol);
• MANSRTSP (Monitoring and Alarming Network System Real Time Streaming Protocol).

This allows receiving the status of sensors, events from detectors, PTZ and relays control, access the built-in archive of the IP device (make sure to set the correct device time zone in the C-Werk), etc. within the SIP session. Single-channel and multi-channel devices in single-stream mode and working with the UDP and TCP transport protocols is also supported.

At the same level of the OSI model, the RTP/RTCP protocol also works in parallel with the SIP protocol, which makes it possible to use the following functions:

• video transmission (including archival) in H264, H265, or MJPEG format;
• audio transmission in G.711a, G.711u, or G.726 format in PS (Program Stream) only. Archive audio is not supported.
  

For the most up-to-date information on this standard and the features supported in C-Werk, see the Documentation Drivers Pack.

Configuring an IP-device to operate via GB/T28181 standard

Configuration of IP devices connected via GB/T28181 is performed through the web interface of the devices. Settings are not sent from C-Werk to the device.

Before connecting a camera via this protocol to C-Werk, perform the following steps to configure SIP on the device:

1. Set the Server IP to equal the Server's IP address.
2. Set the Server port (5060 by default).
3. Set the Device ID. The ID should be set on all cameras connected via the GB/T28181 protocol and must be unique. The format of the connection code (device ID and server ID) is a 20-digit number:
   
   1. the first 10 digits specify the address (according to the GB/T-2260-2007 standard);
      
   2. the next 10 digits indicate device information.
      If the IP device is located behind NAT, then forward and explicitly specify the external address of the Server, the port/port range for receiving video, and the SIP port of C-Werk Server. Example: 34020000001110000001/50557-51557@10.3.3.11/85.172.174.36​
      
4. For the device to perform autodiscovery of the Server more quickly, reduce the default value of RefreshRegTime. The name of this setting may vary on some cameras.

Configuring IP-device connection via GB/T28181

After configuring the device as described earlier, add it to C-Werk as follows:

1. Run the IP discovery wizard (see Adding and removing IP devices).
2. In the form for manually adding an IP device, in the Vendor list, select GBT28181 (1).
   
   

3. In the IP address field specify the value of Device ID parameter set during IP device configuration (2). The following additional parameters can be specified optionally as follows:
   [gbt://]deviceID[/videoPort]@serverID[-serverLocalIP[/serverExternalIP]]
   OR
   [gbt://]deviceID[/videoPortFirst-videoPortLast]@serverID[-serverLocalIP[/serverExternalIP]]
   where:

   • deviceID is the Device ID parameter;

   • serverID is the identifier of the C-Werk Server generated according to the same rules as the IP device ID (see above);

   • videoPort is the port for receiving video;

   • videoPortFirst − videoPortLast is range of ports for receiving video;

   • serverLocalIP is the local IP address of the C-Werk Server, which sets the network interface on which the Server should be available;

   • serverExternalIP is the global IP address of the C-Werk Server; this parameter is in use when the C-Werk Server is behind the gateway. In this case, this IP address is specified as the SIP Server IP address in the IP device settings.

     Examples.

     34020000001320000008@34020000002000000001

     34020000001320000008@34020000002000000001-10.0.40.246/113.125.160.58 
     34020000001320000008@34020000002000000001-10.0.40.246 
     34020000001320000008@34020000002000000001-/113.125.160.58 
     34020000001320000008/50200@34020000002000000001 
     34020000001320000008/50200-50210@34020000002000000001-10.0.40.246

4. In the Port field, enter the local port number that the C-Werk Server shall listen for receiving messages from the IP device (3). Usually this is the default SIP port: 5060.
   

   Note.

   The IP device SIP port is detected automatically.

5. The Username and the Password fields are not used (4).
6. Click the  button.

Connection of the camera via GB/T28181 is now complete.