Time Slot Assignment Algorithm with Graph Coloring

그래프 채색에 의한 타임 슬롯 할당 알고리즘

  • 권보섭 (안동대학교 컴퓨터교육과)
  • Published : 2008.05.31


A simple Time Division Multiplex(TDM) switching system which has been widely in satellite networks provides any size of bandwidth for a number of low bandwidth subscribers by allocating proper number of time slots in a frame. In this paper, we propose a new approach based on graph coloring model for efficient time slot assignment algorithm in contrast to network flow model in previous works. When the frame length of an initial matrix of time slot requests is 2's power, this matrix is divided into two matrices of time slot requests using binary divide and conquer method based on the graph coloring model. This process is continued until resulting matrices of time slot requests are of length one. While the most efficient algorithm proposed in the literature has time complexity of $O(N^{4.5})$, the time complexity of the proposed algorithm is $O(NLlog_2L)$, where N is the number of input/output links and L is the number of time slot alloted to each link in the frame.


  1. M. A. Bonuccelli, F. Martelli, and S. Pelagatti, "Optimal Packet Scheduling in tree-structured LEO Satellite Cluster," Mobile Networks and Application, Vol.9, pp.289-295, 2004.
  2. K. T. Yiu, "Scheduling Satellite- Switched Time-Division Multiple Access With Geneneral Switching Modes," IEEE/ACM Trans, Vol.12, No.4, 2004(8).
  3. K. Y. Eng and A. S. Acampora, " Fundamental Conditions Governing TDM Switching Assignments in Terrestrial and Satellite Networks," IEEE Trans. on Commun., Vol.35, pp.755-761, 1987(7).
  4. S. C Liew, "Comments on `Fundamental Conditions Governing TDM Switching Assignments in Terrestrial and Satellite Networks'," IEEE Trans, on Commun, Vol.37, pp.187-189, 1989(2).
  5. G. Haigang and L. Ming, "A Two Level TDMA Scheduling Protocol with Intra-cluster Coverage for Large Scale Wireless Sensor Network," IJCSNS, Vol.6, No.2B, 2006(2).
  6. M. A. Bonuccelli, "A Fast Time-slot Assignment Algorithm for TDM Hierarchical Switching System," IEEE Trans, on Commun., Vol.37, pp.870-874, 1989(8).
  7. M. A. Bonuccelli, I. Gopal, and C. K. Wong, "Incremental Time-Slot Assignment in SS/TDMA Satellite Systems," IEEE Trans. on Commun., Vol.39, pp.1147-1156, 1991(7).
  8. S. Chalasani and A. Varmar, "An improved Time-slot Assignment Algorithm for TDM Hierarchical Switching Systems," IEEE Trans. on Commun., Vol.41, pp.312-317, 1993(2).
  9. S. Chalasani and A. Varmar, Parallel Algorithms for Time-slot Assignment in TDM Switching System," IEEE Trans. on Commun., Vol.41 pp.1736-1747, 1993(11).
  10. ISaac Keslassy, Murali Kodialam, T. V. Lakshman, and Dimitrios Stiliadis, "On Guaranted Smooth Scheduling for Input-Queued Switches," IEEE/ACM Trans., Vol.13, No.6, 2005(12).
  11. K. T. Yiu, "A unified Algorithmic Framework for Variable-Rate TDM Switching Assignments," IEEE/ACM Trans., on Networking, Vol.9, No.5, 2001(10).
  12. S. Kulkarni, "TDMA service for sensor network," In 24th Int. Conf. on Distributed Computing Systems(ICDCS04), ADSN Workshop, pp.604-609, 2004(3).
  13. S. Suresh, J. Eric, Harder, and H. A. Choi, "Scheduling multi-rate sessions in time division multiplexed wavelength-routing networks," IEEE Journal on Selected Areas in Communications, Vol.18, No.10, 2000(10)