A method of determining loss of IP packets that are transported over a network (102), where each IP packet comprises a number of data packets. The method comprises: i) extracting (501) a first data packet from a first IP packet (41), ii) extracting (502) a second data packet from a second IP packet, iii) retrieving (503, 504) a first sequence number from a first data packet and a second sequence number from a second data packet, where each of the sequence numbers is indicative of a sequence of data packets and has a value belonging to a set of a number of unique values, iv) calculating (505) a difference (Δcc) between the sequence numbers, and v) determining (506) a number (k) of lost IP packets, as a function of the difference (Δcc) between the sequence numbers. Related computer readable medium and customer equipment are also described.