The application relates to the communication technical field, and provides a seamless
roaming method and
system. The method comprises the following steps: receiving a first frame sent by a
station; determining a target access point based on the first frame; sending context information of the
station to the target access point, and receiving response information sent by the target access point; setting a value of an access category (AC) to which a second frame belongs as a value of a voice category (AC_VO), or setting a value of an AC to which the second frame belongs as a new value; and sending the second frame to the
station. In the process of switching the access point, the value of the AC to which the second frame belongs is set as the value of the voice category (AC_VO), or the value of the AC to which the second frame belongs is set as the new value, so that, compared with other to-be-executed processes of a source access point, the sending process of the second frame can be preferentially executed by the source access point, thereby the
interaction time length of the overall switching process can be reduced, the
packet loss rate can be reduced, the service
lag can be avoided, and the user experience can be improved.