A Method Of Determining Passive Round Trip Time, RTT, Delay In A Telecommunications System

摘要

A method of determining a passive Round Trip Time, RTT, delay in a telecommunications system (1) for exchanging data packets (2a-2d) in accordance with a data transmission protocol between a first device (4) and a second device (6). The first device (4) identified by a first device identification, and the second device (6), identified by a second device identification. The data packets (2a-2d) comprising an address part (3) including a source address and a destination address. The method performed in a node (5) by modifying the address part (3) of a received data packet (2a) from a the first device (4), and creating a first timestamp, before transmitting the modified data packet (2b) to the second device (6). Upon receiving, at the node (5), from the second device (6) in response to the modified data packet (2b), a data packet (2c) having the modified address part (3) of the modified data packet (2b), creating a second timestamp at the node (5) provides for passively measuring the RTT delay.