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The Narrow Band Interface User Plane (NbUP) protocol is now available on Dialogic® Host Media Processing (HMP) Software Release 3.1 for Linux and Dialogic® Multimedia Software Release 1.1 as a transport for 3G-324M. It allows 3G-324M to send its multiplexed audio, video and call control over an IP connection, rather than a TDM DS0 timeslot. To do this, it uses the Dialogic® IPML API.

There are two code snippets in the IPML documentation under the ipm_SendInit and ipm_InitResponseSend API calls. These are used as the basis for this example. This tech note presents a brief introduction to how the samples work, and provides code download that demonstrates setting up an NbUP connection. Note that only the IPML connection is shown here; no use of it is made by 3G-324 and the Dialogic® M3G API. This is planned for an upcoming version of the 3G-SIP gateway demo, which is distributed with the Dialogic Multimedia Software and Dialogic HMP Software for Linux.

The demo consists of two processes that are intended to be run on the same system. They open their respective IPML devices, and then set up for and establish a NbUP connection with one another. The connection is then torn down and the devices closed.

The diagram below shows the sequence of events needed to do this: 

Send Side					Receive Side 
--------- 				        ------------ 
 

Open IPM device 				Open IPM device
 



Enable IPM events 				Enable IPM events
 

Request IPM Local media params 		        Request IPM Local Media params
 

Setup IPM media for NbUP 			Setup IPM media for NbUP
 

Start IPM media 				Start IPM media and wait for NbUP initialzation msg
 

Send NbUP init msg           --------------> 	App gets IPMEV_INIT_RECEIVED event
 


App gets IPMEV_INIT_COMPLETE <-------------- 	App sends init response message




 

 		--- NbUP connection can now be used by 3G-324M ----
 






IPM media stopped 				IPM media stopped
 


Close IPM device 				Close IPM device

Running the Demo
Build each of the halves of the demo in their respective directories by issuing a "make". Two licensed IPML devices, ipmB1C1 and ipmB2C2 are needed. Start the nbup_receive side first, followed by the nbup_send side. API calls and events received are sent to stdout and can be examined to get a feel for how the protocol is set up.

Related Documentation

IPML API Reference for Dialogic HMP Software for Linux - www.dialogic.com/manuals/docs/ip_media_api_hmp_v10.pdf
IPMP API Reference for Dialogic Multimedia Software - www.dialogic.com/manuals/docs/ip_media_api_hmp_v9.pdf