A message transmitting method, comprising: dividing access signals into a first pre-determined number of access signal groups, wherein the access signal groups correspond to pre-determined access response resources (S1a02); receiving an access signal, which is transmitted in an access beam form based on one or more access signal groups, from a second communication node, wherein the one or more access signal groups are selected by the second communication node according to a division result (S1a04); determining an access signal group to which the access signal pertains, wherein one or more access signals contained in the determined access signal group are transmitted under at least one of the following restriction conditions: a restricted sequence transmitting order, a restricted transmitting occasion, and a restricted transmitting frequency domain position (S1a06); and transmitting an access response message to the second communication node over an access response resource corresponding to the determined access signal group (S1a08); the second communication node receiving information on a correspondence between resource sets and access signal groups; wherein dividing the access signals into the first pre-determined number of access signal groups (S1a02) comprises: dividing the access signal groups into a second pre-determined number of detection threshold grades; and dividing the access signals into the first pre-determined number of access signal groups according to the divided grades, wherein different numbers of access signals are divided in access signal groups under different grades; the same number of access signals is divided in access signal groups under an identical grade, or the difference of numbers of the access signals divided in the access signal groups under the identical grade is smaller than a pre-determined threshold number. dividing access signals into a first pre-determined number of access signal groups, wherein the access signal groups correspond to pre-determined access response resources (S1a02); receiving an access signal, which is transmitted in an access beam form based on one or more access signal groups, from a second communication node, wherein the one or more access signal groups are selected by the second communication node according to a division result (S1a04); determining an access signal group to which the access signal pertains, wherein one or more access signals contained in the determined access signal group are transmitted under at least one of the following restriction conditions: a restricted sequence transmitting order, a restricted transmitting occasion, and a restricted transmitting frequency domain position (S1a06); and transmitting an access response message to the second communication node over an access response resource corresponding to the determined access signal group (S1a08); the second communication node receiving information on a correspondence between resource sets and access signal groups; wherein dividing the access signals into the first pre-determined number of access signal groups (S1a02) comprises: dividing the access signal groups into a second pre-determined number of detection threshold grades; and dividing the access signals into the first pre-determined number of access signal groups according to the divided grades, wherein different numbers of access signals are divided in access signal groups under different grades; the same number of access signals is divided in access signal groups under an identical grade, or the difference of numbers of the access signals divided in the access signal groups under the identical grade is smaller than a pre-determined threshold number. <EOS>