QoS-specified Traffic Grooming Algorithm in WDM Mesh Networks

1
QoS-specified Traffic Grooming Algorithm in WDM
Mesh Networks

• Bing Xiang, Hongfang Yu, Sheng Wang, Lemin Li

Communications, Circuits and Systems, 2004.
ICCCAS 2004. 2004 International Conference
onVolume 1,  27-29 June 2004 Page(s)633 - 637
Vol.1
2
Abstract

• In WDM network, the bandwidth request of a
  traffic stream is usually much lower than the
  capacity of a wavelength.
• Traffic grooming can aggregate low-rate
  connections into high-capacity lightpaths to make
  efficient use of the bandwidth.
• Authors propose a QoS-specified traffic grooming
  algorithm named BMST considering both the hops of
  lightpath and load balance in the network.

3
Introduction(1/5)

• A WDM network consists of WDM switches (OXCs)
  connected by fiber optical links.
• In each link, multiple wavelengths are available.
  OXCs enable space-switching of wavelengths from
  one port to another and help in establishuig
  circuit-switched connections called lightpaths
  between the nodes.
• This enables optical passthrough at the WDM layer
  and eliminates the need to electronically process
  all the traffic at the node

4
Introduction(2/5)

• Usually we can setup lightpaths using designate
  RWA in WDM networks ,but for the RWA, there exist
  an assumption that every connection required a
  full wavelength.
• The network may be required to support traffic
  connections at rates that are much lower than the
  full wavelength capacity.
• For networks of practical size, the number of
  available wavelengths is still lower than the
  number of source to destination connections that
  need to be made.

5
Introduction(3/5)

• Traffic grooming can aggregate low-rate
  connections onto high-capacity lightpaths to make
  efficient use of the wavelength capacity.
• Most of the researches related to traffic
  grooming focused on WDM/SONET ring networks while
  fewer studies of traffic grooming in WDM mesh
  network such as 12 are presented to maximize
  the network throughput.
• The basic idea in Literature 12 can be
  described as follow
• set up the single-hop lightpaths as much as
  possible subject to the network resources.
• use the single hop work lightpaths to construct
  virtual topology.
• low-rate connections can be groomed in the
  virtual topology accordingly.

6
Introduction(4/5)

• In the studies list above, no consideration has
  addressed on QoS based traffic grooming.
• The QoS-specified RWA algorithms proposed in 13
  only suggest to setup three kinds of lightpath to
  support different QoS levels, those are Dedicated
  lightpath, Shared lightpath 'and Multi-hop
  lightpath respectively, But the traffic grooming
  is not considered.
• Since the load distribution of network can
  exercise great influence on the average
  transmission delay of traffic, load balance of
  network traffic can improve network performance
  efficiently.

7
Introduction(5/5)

• In this paper authors propose a QoS-specified
  traffic grooming algorithm named BMST, Balanced
  Maximizing Single-Hop Traffic grooming Algorithm,
  considering both the hop of lightpath and load
  balance in WDM mesh networks.

8
References

• 12 K.Y. Zhu, B. Mukherjee, Traffic Grooming in
  an Optical WDM Mesh Network, IEEE J. Select.
  Areas Comm., Vol. 20, N. 1, pp122-133, January
  2002.
• 13 Y. Qin, K. Sivalingam, B. Li, QoS for
  Virtual Private Networks over Optical WDM
  Networks, SPIE/ACM/IEEE Opticomm conference at
  Dallas, TX, October 2000.