Data transmission and measurement techniques

A method for wireless communication, comprising:

• receiving, at a second network element, data from a first network element;
• transmitting, at the second network element, feedback data to the first network element, where the feedback data includes a highest delivered packet data convergence protocol (PDCP) sequence number (SN) and information indicative of a range of data that has been successfully delivered to a terminal;
• and
• receiving at least a portion of data retransmitted from the first network element based on the feedback data.

An apparatus for wireless communication comprising a processor that is configured to perform a method, the processor being configured to:

• transmit data from a first network element to a second network element;
• receive, at the first network element, feedback data from the second network element, where the feedback data includes a highest delivered packet data convergence protocol (PDCP) sequence number (SN) and information indicative of a range of data that has been successfully delivered to a terminal;
• and
• retransmit at least a portion of the data from the first network element based on the feedback data.

An apparatus for wireless communication comprising a processor that is configured to perform a method, the processor being configured to:

• receive, at a second network element, data from a first network element;
• transmit, at the second network element, feedback data to the first network element, where the feedback data includes a highest delivered packet data convergence protocol (PDCP) sequence number (SN) and information indicative of a range of data that has been successfully delivered to a terminal;
• and
• receive at least a portion of data retransmitted from the first network element based on the feedback data.