[Contents] [Prev] [Next] [Index] [Report an Error]

Detecting Hanging Terminations

Synchronization of termination information between the PG and the PGC is essential for traffic, maintenance, and charging purposes. If a termination does not exchange messages for a period of time, corresponding data for the termination might be mismatched on the PG and the PGC, and the termination can be hanging. Hanging terminations can consume resources that can be used for chargeable calls.

To detect possible hanging terminations, the PG uses a timer that begins when a message is exchanged for a specific termination. If the termination does not receive a message when the timer expires, the PG notifies the PGC. If the data on the PGC does not match the data on the PG, the PGC returns one of the following error messages to the PG:

Error Code #: 411 Name: The transaction refers to an unknown ContextID
Error Code #: 430 Name: Unknown TerminationID
Error Code #: 435 Name: Termination ID is not in specified Context

The PGC is responsible for correcting mismatches in data. For example, the PGC can subtract the indicated termination and clear associated contexts. The PGC can also audit the termination service state to check its records before taking further action.

Activating and Configuring Hanging Termination Detection

The timerx timer sets the interval between the last message exchanged for a specific termination and when the PG sends a notification to the PGC. The timer resets when a message is exchanged on the termination and when the PG notifies the PGC. For example, if the PG notifies the PGC that there has been no activity on the termination, and the PGC does not modify or subtract the indicated termination, the PG again waits the specified time, and sends another notification if there still has not been activity on the termination.

Setting the timer to a value other than zero (0) activates hanging termination detection on new and modified terminations. The timer value that you set is the default value, and it can be overridden by H.248 messages sent from the PGC. To set the timer:



[edit services pgcp gateway vpg-1 h248-properties hanging-termination-detection]
user@host#set timerx 30

Deactivating Hanging Termination Detection

To deactivate hanging termination detection, set the timerx statement to 0:



[edit services pgcp gateway vpg-1 h248-properties hanging-termination-detection]
user@host#set timerx 0

Displaying the Value of the Timerx Timer Configured on the VPG

Purpose

Display the value of the timerx that is configured on the VPG

Action

[edit services pgcp gateway vpg-1 h248-properties
hanging-termination-detection]

user@host# show

timerx 30;

Displaying the Value of the Hanging Termination Timer for a Termination

Purpose

Display the timerx value for a termination.

Action

user@host> show services pgcp terminations
vpg-1 h248

Termination information:
ip/4/vif-0/2 {
      MEDIA {
        TERMINATIONSTATE { SERVICESTATES = INSERVICE },
        STREAM = 1 {
          LOCALCONTROL { MODE = SENDRECEIVE, GM/LSP = 0 }, 
           LOCAL {       
            v = 0,
            c=IN IP4 10.50.100.1
            m=- 1080 RTP/AVP  — 
            b=AS:0
          }
        }
      }
      EVENTS { HANGTERM/THB { TIMERX = 30 } }    
}

[Contents] [Prev] [Next] [Index] [Report an Error]