Method for determining a route distance value

• US 7,881,212 B2
• Filed: 01/26/2007
• Issued: 02/01/2011
• Est. Priority Date: 03/30/2006
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Kutschenreuter, Matthias, Schwingenschlogl, Christian
• Primary Examiner(s): Ngo, Ricky
• Assistant Examiner(s): Zaidi, Iqbal
• Application Number:
  US12/225,818
• Publication Number:
  US 20090232014A1
• Time in Patent Office: 1,467 Days
• Field of Search: 370/351, 370229-240, 370/248, 370/265, 370/252, 455/445, 709/238, 709/226, 709/229
• US Class Current: 370/248
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/123 Evaluation of link metrics techniques for monitoring network metrics H04L43/08

Abstract

A method determines a route in distance value for use in routing protocols. An optimum route is determined for time-critical transmissions such as videotelephony or VoIP. For this purpose, the route distance value is calculated as the product of the link metrics for the links of a route, said link metrics being the product of data packet arrival rates. This value is the optimum value for the route which requires the lowest number of repeated packet transmissions (retransmissions). Optionally, an additional factor can be inserted in the link metrics, which factor ensures that the length of a route is also taken into consideration.

Claims

1. A method for determining a preferred path for data packet transmission among a plurality of candidate paths, each candidate path extending from a transmitting node to a receiving node over one or more links, at least one candidate path extending through at least one intermediate node such that the at least one candidate path has at least two links, comprising:

determining, for each link, a link distance value, each link distance value being determined based on a first probability that a data packet will be successfully transmitted over the respective link, each link distance value being determined for a first transmission direction of the respective link based on a first data packet arrival rate that is included in the first probability and for a second transmission direction opposite to the first transmission direction of the respective link based on a second data packet arrival rate that is included in the first probability;

determining, for each candidate path, a path distance value based on a second probability that, during a transmission along the respective candidate path, a data packet must be repeatedly transmitted over at least one link and the link distance value determined for each of the links;

comparing the path distance value determined for each of the candidate paths with a threshold value; and

rejecting a respective candidate path when the path distance value of the respective path is below the threshold value.

2. The method as claimed in claim 1, wherein the link distance values are adjusted based on a first product of the respective first and the second data packet arrival rates.

3. The method as claimed in claim 2, wherein the link distance values are multiplied to produce a second product, and each path distance value is determined based on the second product.

4. The method as claimed in claim 3, wherein the second product contains an additional factor based on the number of links in the respective path.

5. A network node, comprising:

a processing device configured to perform the method of claim 1.

6. A network comprising a plurality of network nodes, each node comprising:

a processing device configured to perform the method of claim 1.