As networks have become an important infrastructure in everyday life in recent years, the need to increase the degree of quality control has also arisen. Because it is necessary to accurately understand the state of the network for quality control, time information on measurement equipment has become important Consequently, we have aimed at improving the precision of time synchronization through the network and propose highly precise time synchronization techniques that utilize network support Two approaches are MQL (maximum queue length) and QTL (queue to live) both employing the suggested "self-discarding packet technique", which is a means of determining transfer by comparing the queue length of the transiting router with a specified queue value on the probing packet. In this paper, we clarify the influence a router has on the precision of time synchronization and report these two approaches and their adaptability.