Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls

The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature provides dynamic payload type interworking for dual tone multifrequency (DTMF) and codec packets for Session Initiation Protocol (SIP) to SIP calls.

Based on this feature, the Cisco Unified Border Element (Cisco UBE) interworks between different dynamic payload type values across the call legs for the same codec. Also, Cisco UBE supports any payload type value for audio, video, named signaling events (NSEs), and named telephone events (NTEs) in the dynamic payload type range 96 to 127.

Feature Information for Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Table 1 Feature Information for Dynamic Payload Interworking for DTMF and Codec Packets Support

Feature Name

Releases

Feature Information

Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls

15.0(1)XA 15.1(1)T

The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature provides dynamic payload type interworking for DTMF and codec packets for SIP-to-SIP calls.

The following commands were introduced or modified: asymmetric payload and voice-class sip asymmetric payload.

Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls

Cisco IOS Release XE 3.1S

The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature provides dynamic payload type interworking for DTMF and codec packets for SIP-to-SIP calls.

The following commands were introduced or modified: asymmetric payload and voice-class sip asymmetric payload.

High Availability Checkpointing Support for Asymmetric Payload

Cisco IOS Release XE 3.12S

High availability support for asymmetric payload type interworking was added.

Restrictions for Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls

The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature is not supported for the following:

  • H323-to-H323 and H323-to-SIP calls.

  • All transcoded calls.

  • Secure Real-Time Protocol (SRTP) pass-through calls.

  • Flow-around calls.

  • Asymmetric payload types are not supported on early-offer (EO) call legs in a delayed-offer to early-offer (DO-EO) scenario.

  • Cisco fax relay.

  • Multiple m lines with the same dynamic payload types, where m is:

m = audio <media-port1> RTP/AVP XXX m = video <media-port2> RTP/AVP XXX

Symmetric and Asymmetric Calls

Cisco UBE supports dynamic payload type negotiation and interworking for all symmetric and asymmetric payload type combinations. A call leg on Cisco UBE is considered as symmetric or asymmetric based on the payload type value exchanged during the offer and answer with the endpoint:

  • A symmetric endpoint accepts and sends the same payload type.

  • An asymmetric endpoint can accept and send different payload types.

The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature is enabled by default for a symmetric call. An offer is sent with a payload type based on the dial-peer configuration. The answer is sent with the same payload type as was received in the incoming offer. When the payload type values negotiated during the signaling are different, the Cisco UBE changes the Real-Time Transport Protocol (RTP) payload value in the VoIP to RTP media path.

To support asymmetric call legs, you must enable The Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature. The dynamic payload type value is passed across the call legs, and the RTP payload type interworking is not required. The RTP payload type handling is dependent on the endpoint receiving them.

High Availability Checkpointing Support for Asymmetric Payload

High availability for a call involving asymmetric payloads is supported. In case of fail-over from active to stand-by, the asymmetric payload interworking will be continued as new active CUBE passes across the payload type values according to the negotiation and call establishment.
Figure 1. Sample High-Availability Topology



How to Configure Dynamic Payload Type Passthrough for DTMF and Codec Packets for SIP-to-SIP Calls

Configuring Dynamic Payload Type Passthrough at the Global Level

Perform this task to configure the pass through of DTMF or codec payload to the other call leg (instead of performing dynamic payload type interworking) feature at the global level.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    voice service voip

    4.    sip

    5.    asymmetric payload {dtmf | dynamic-codecs | full | system}

    6.    end


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example: 
    Device> enable


    Example: 
    
 
			 
    
 
		   
          		  
			 
     Enables
				privileged EXEC mode. 
			 
    
 
			 
    •  
				  
       Enter your
					 password if prompted. 
				  
      
 
				
      • 

    
 
		   
      
    

    Step 2 
			  
				configure 
			  
			  
				terminal 
			  
		  
     

    Example: 
			 
     
				
    Device# configure terminal
    
 
			 
    
 
		   
          		  
			 
     Enters global
				configuration mode. 
			 
    
 
		   
      
    

    Step 3 
			  
				voice 
				service 
			  
			  
				voip 
			  
		  
     

    Example: 
			 
     
				
    Device(config)# voice service voip
    
 
			 
    
 
		   
          		  
			 
     Enters voice
				service configuration mode. 
			 
    
 
		   
      
    

    Step 4 
			  
				sip 
			  
		  
     

    Example: 
			 
     
				
    Device(conf-voi-serv)# sip
    
 
			 
    
 
		   
          		  
			 
     Enters voice
				service SIP configuration mode. 
			 
    
 
		   
      
    

    Step 5 
			  
				asymmetric 
				payload 
			  {dtmf | 
			 dynamic-codecs
			 | 
			 full | 
			 system} 
		  
     

    Example: 
			 
     
				
    Device(conf-serv-sip)# asymmetric payload full
    
 
			 
    
 
		   
          		  
			 
     Configures
				global SIP asymmetric payload support. 
			 
    
 
			 
    Note   
                
               
				
     The 
				  dtmf and 
				  dynamic-codecs
				  keywords are internally mapped to the 
				  full keyword to
				  provide asymmetric payload type support for audio and video codecs, DTMF, and
				  NSEs. 
				
    
 
			 
    
 
		   
      
    

    Step 6 
			  
				end 
			  
		  
     

    Example: 
			 
     
				
    Device(conf-serv-sip)# end
    
 
			 
    
 
		   
          		  
			 
     Exits voice
				service SIP configuration mode and enters privileged EXEC mode. 
			 
    
 
		   
      
    

    

    

    

    Configuring Dynamic Payload
	 Type Passthrough for a Dial Peer
    

     
		
     Perform this task
		  to configure the pass through of DTMF or codec payload to the other call leg
		  (instead of performing dynamic payload type interworking) feature at the
		  dial-peer level. 
		
    
 
	 
    
SUMMARY STEPS
      1.   
       
			  
				enable
				
			  
		  
      

      2.   
       
			  
				configure 
			  
			  
				terminal 
			  
		  
      

      3.   
       
			  
				dial-peer 
				voice 
			  
			  
				tag 
			  
			  
				voip 
			  
		  
      

      4.   
       
			  
				voice-class 
				sip 
				asymmetric 
				payload 
			  {dtmf | 
			 dynamic-codecs
			 | 
			 full | 
			 system} 
		  
      

      5.   
       
			  
				end 
			  
		  
      


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 
			  
				enable
				
			  
		  
       

      Example: 
			 
       
				
      Device> enable
      
 
			 
      
 
		   
            		  
			 
       Enables
				privileged EXEC mode. 
			 
      
 
			 
      •  
				  
         Enter your
					 password if prompted. 
				  
        
 
				
        • 

      
 
		   
      
      

      Step 2 
			  
				configure 
			  
			  
				terminal 
			  
		  
       

      Example: 
			 
       
				
      Device# configure terminal
      
 
			 
      
 
		   
            		  
			 
       Enters global
				configuration mode. 
			 
      
 
		   
      
      

      Step 3 
			  
				dial-peer 
				voice 
			  
			  
				tag 
			  
			  
				voip 
			  
		  
       

      Example: 
			 
       
				
      Device(config)# dial-peer voice 77 voip 
      
 
			 
      
 
		   
            		  
			 
       Enters dial
				peer voice configuration mode. 
			 
      
 
		   
      
      

      Step 4 
			  
				voice-class 
				sip 
				asymmetric 
				payload 
			  {dtmf | 
			 dynamic-codecs
			 | 
			 full | 
			 system} 
		  
       

      Example: 
			 
       
				
      Device(config-dial-peer)# voice-class sip asymmetric payload full
      
 
			 
      
 
		   
            		  
			 
       Configures the
				dynamic SIP asymmetric payload support. 
			 
      
 
			 
      Note   
                
               
				
       The 
				  dtmf and 
				  dynamic-codecs
				  keywords are internally mapped to the 
				  full keyword to
				  provide asymmetric payload type support for audio and video codecs, DTMF, and
				  NSEs. 
				
      
 
			 
      
 
		   
      
      

      Step 5 
			  
				end 
			  
		  
       

      Example: 
			 
       
				
      Device(config-dial-peer)# end
      
 
			 
      
 
		   
            		  
			 
       (Optional)
				Exits dial peer voice configuration mode and enters privileged EXEC mode. 
			 
      
 
		   
      
      

      

      

      

      Verifying Dynamic Payload Interworking for DTMF and Codec Packets Support
      

       
		
       This task shows how to display information to verify Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls configuration feature. These 
		  show commands need not be entered in any specific order. 
		
      
 
	 
      
SUMMARY STEPS
        1.   
       
			  
				enable 
			  
		  
        

        2.   
       
			  
				show 
				call 
				active 
				voice 
				compact 
			  
		  
        

        3.   
       
			  
				show 
				call 
				active 
				voice 
			  
		  
        


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 
			  
				enable 
			  
		  
         

        Example:
         
			 
        Device> enable
        
 
		  
        
 
              		  
			 
         Enables privileged EXEC mode. 
			 
        
 
			 
        •  Enter your password if prompted.
				
          

          • 

        
 
		   
      
        

        Step 2 
			  
				show 
				call 
				active 
				voice 
				compact 
			  
		  
         

        Example:
         
			 
        Device# show call active voice compact
        
 
		  
        
 
              		  
			 
         (Optional) Displays a compact version of call information. 
			 
        
 
		   
      
        

        Step 3 
			  
				show 
				call 
				active 
				voice 
			  
		  
         

        Example:
         
			 
        Device# show call active voice
        
 
		  
        
 
              		  
			 
         (Optional) Displays call information for voice calls in progress.
			 
        
 
		   
      
        

        

        

        

        Troubleshooting Tips
        

        
Use the following commands to debug any errors that you may encounter when you configure the  Dynamic Payload Type Interworking for DTMF and Codec Packets for SIP-to-SIP Calls feature:
        

        • 
        
          debug
          ccsip
          all
        
      
          

          • 

        • 
        
          debug
          voip
          ccapi
          inout	
        
      
          

          • 

        • 
        
          debug
          voip
          rtp
        
      
          

          • 

        

        Use the following debug commands to troubleshoot HA Checkpointing for Asymmetric Payload:
        

        • debug voip ccapi all
          • 

        • debug voice high-availability all
          • 

        • debug voip rtp error
          • 

        • debug voip rtp inout
          • 

        • debug voip rtp packet
          • 

        • debug voip rtp high-availability
          • 

        • debug voip rtp function
          • 

        • debug ccsip all
          • 

        

        Use the following show commands to troubleshoot HA Checkpointing for Asymmetric Payload:
        

        • show redundancy state
          • 

        • show redundancy inter-device
          • 

        • show standby brief
          • 

        • show voice high-availability summary
          • 

        • show voip rtp stats
          • 

        • show voip rtp high-availability stats
          • 

        • show voip rtp connection detail
          • 

        • show call active voice brief
          • 

        • show call active voice [summary]
          • 

        • show call active video brief
          • 

        • show call active video [summary]
          • 

        • show align
          • 

        • show memory debug leak
          • 

        

        

        

        

        Configuration
	 Examples for Assymetric Payload Interworking
        

        Example: Asymmetric Payload Interworking—Passthrough Configuration
        

        

        
            
            
        !
voice service voip 
 allow-connections sip to sip
sip
  rel1xx disable
  asymmetric payload full
  midcall-signaling passthru
!
dial-peer voice 1 voip
 voice-class sip asymmetric payload full
 session protocol sipv2
 rtp payload-type cisco-codec-fax-ind 110
 rtp payload-type cisco-codec-video-h264 112
 session target ipv4:9.13.8.23
!

        

        
        

        

        

        Example:
	 Asymmetric Payload Interworking—Interworking Configuration
        

        

         
		
        !
voice service voip 
 allow-connections sip to sip
!
dial-peer voice 1 voip
 session protocol sipv2
 rtp payload-type cisco-codec-fax-ind 110
 rtp payload-type cisco-codec-video-h264 112
 session target ipv4:9.13.8.23
!