Pgm_Source_Max_Trans_Rate

The Pgm_Source_Max_Trans_Rate option specifies the maximum rate, in bits a second (bps), at which RTgms attempts to send multicast messages. This value includes repair data sent in response to NAKs, in addition to data being sent for the first time. If RTgms attempts to send faster than this rate, data is queued on the admit queue up to the value you set for Pgm_Source_Admit_High.

Setting the value for Pgm_Source_Max_Trans_Rate improperly causes inefficient network use. If the value is smaller than the rate messages can be delivered by the network between RTgms and the RTclients, you are setting an artificial limit on the rate at which RTgms sends messages. This means the multicast messages are sent more slowly than they need to be. However, if you set the value higher than the rate messages can be delivered by the network between RTgms and the RTclients, this can cause excessive data loss in the network. More NAKs are generated, and more of the available network bandwidth is used for repair data, reducing the amount available to the original messages.

You can dynamically set the value for Pgm_Source_Max_Trans_Rate on a connection basis, using an ADMIN_SET message. For more information, see the information on the T_MT_GRP_ADMIN_SET_PGM_OPTIONS message.