The present invention proposes a method for scheduling resource in a packet network and a network element for exchanging signaling with user equipments, wherein user equipments communicate therebetween using the resource allocated by network elements, said communication comprises talk-spurt periods during which data packets are transmitted and silent periods during which silence descriptor packets are transmitted, said method for scheduling resource comprising: said network element allocates resource for said user equipments for communication; both said user equipment and said network element detect the presence of said silence descriptor packet, and said network element determines the optimized number of resource unit(s) to be allocated to said user equipment during the interval for transmitting said data packet, based on the coding rate of said user equipment, the selected modulation coding scheme and the valid transmission times; the network element starts timing and the user equipment stops using the allocated resource if a silence descriptor packet is detected; when the timing finishes or a request for allocating resource is received from the user equipment before the end of said timing, said network element allocates the determined optimized number of resource unit(s) to said user equipment, and said user equipment begins to use said determined optimized number of resource unit(s); said network element determines the end of the interval for transmitting said data packet by detecting the silence descriptor packet.; and when both said user equipment and said network element detect a silence descriptor packet, said user equipment stops using said determined optimized number of resource unit(s), while said network element releases said determined optimized number of resource unit(s).