Method, a computer program product, and a carrier for indicating one-way latency in a data network
Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronisation step, a measuring step, a post-synchronisation step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.
1. A system to determine a one-way latency between a first and a second nodes in a network, comprising:
a first message comprising a first time value sent by the first node to the second node and received by the second node at a third time value;
a second message comprising a fourth time value sent by the second node and received by the first node at a second time value;
a one-way latency profile generated by the first node based on a combination of the first time value, the second time value, the third time value, and the fourth time value.
2. The system of claim 1 further comprising:
a first clock, wherein the first clock determines the first time value and the second time value; and
a second clock, wherein the second clock determines the third time value and the fourth time value.
3. The system of claim 2 wherein the first clock and the second clock are not synchronized.
4. The system of claim 3 wherein the first clock and the second clock are linear with respect to each other over a period required to determine the one-way latency.
5. A method for determining a one-way latency between a first and a second nodes in a network, the method comprising:
sending from the first node to the second node a first message comprising a first time value and receiving at the second node the first message at a third time value;
upon reception of the first message at the second node, sending from the second node to the first node a second message comprising a fourth time value and receiving at the first node the second message at a second time value; and
calculating a one-way latency profile at the first node based on a combination of the first time value, the second time value, the third time value, and the fourth time value.
6. The method of claim 5 further comprising:
determining the first time value and the second time value using a first clock; and
determining the third time value and the fourth time value using a second clock.
7. The method of claim 5 wherein the first clock and the second clock are not synchronized.
8. The method of claim 5 wherein the first clock and the second clock are linear with respect to each other over a period required to determine the one-way latency.