What's new in Gridborg HMP Server 1.3

RTP channel resource

RTP channel resources allow sending and/or receiving media streams to and from external applications by using the real-time transport protocol (RTP). RTP resources can be combined with other resources using Gridborg Server's audio routing facility. Jitter buffer, RTCP and dynamic payload types are supported.

On-demand stream transcoding

Coder and decoder modules are now initiated and utilized only when required, saving you precious CPU cycles and giving you more channels available per host. Gridborg Server always tries to internally operate with the stream in its original form - without bothering of it's content. Only when data really needs to be decoded, Gridborg Server will create and use the appropriate transcoder. One example where you can directly take advantage of this feature is when you know in advance that you will be playing prompts to calls established using some particular codec - by having prompts already stored on disk in that particular format, there will be no transcoding overhead when the prompt file is played.

Flexible codec support

Gridborg Server can now use various audio formats without having available the appropriate codec plugin for coding and decoding that particular format. For example, you can now play G.729 prompts or make G.729 recordings from a call established using G.729 without the codec available and accompanied license fees payed. This is possible because no coding or decoding actually takes place. But, if you tell Gridborg Server to do some processing on that audio (for example mix it with some other audio stream, change it's volume or convert it to other format), G.729 support would still be necessary.

STUN support

Gridborg Server can now be configured to use STUN servers (Simple Traversal of UDP over NAT). STUN is one way of solving NAT traversal problem. Use STUN support if you are having trouble connecting Gridborg Server to endpoints behind firewalls.

Sound device resource

Gridborg Server can now be connected to host's audio input and output lines using one or more sound devices. Each sound device can be at the same time used as input (using line-in or microphone) and output (line-out, headphones). Sound device resources can be used with other resources in any combination. For example, you can add your favorite radio station as a conference participant.

Stereo support

Gridborg Server is now aware and can process stereophonic (dual-channel) audio streams. Player, recorder and sound device resources now fully support stereo mode. Other resources, which are mono by their nature, can be combined with stereo resources - Gridborg Server will automatically make all the transformations when necessary. For example, you can record two-way call into single WAV file, one speaker into left channel and the other speaker to the right channel.

CPU and port usage graphs

You can now monitor your CPU usage and number of active calls using Gridborg Server's web-based interface.

In-band tone generation

DTMF and other in-band signaling tones can now be generated by player resources using the new PlayTone command.

RTCP statistics

RTCP statistics can now be fetched using Gridborg Server control protocol. Applications can use it to monitor network conditions and call quality. This applies both for front-end and RTP channel resources.