A combinational media access protocol for multicast traffic in single-hop WDM lans

1. A combinational media access protocol for multicast traffic in single-hop WDM lans Student : T.H Lin Teacher : H.T Wu Date : 7.28

2. Outline • Introduction • The architecture of single-hop WDM networks • Protocol • The combinational multicast schedule (CMS) • Simulation Results • Conclusions

3. Introduction • Using reservation-based protocol • Partitioning multicast group • Using pre-allocation-based protocol

4. The architecture of single-hop WDM networks • The Passive Star Coupler to connect N nodes. • PSC is an N * N broadcast-and select device interconnected through the optical fibers. • Each node contains one pair of FT-FR to collect the status of multicast traffic, and one pair of FT-TR to access data channel.

5. The architecture of single-hop WDM networks • The network is packet-switched with fix-size packets and operates in a slot mode. • The buffer at each node is assumed to N-1 queues, one dedicated queue and to allocate one queue for multicast transmission.

6. The architecture of single-hop WDM networks • Collision • The arbitration procedure can avoid. • Destination conflict • The receiver wavelength allocation map.

7. Multicast Traffic • Each multicast packet has its own value of M. • M>Md perform multicast transmission. • M<Md the packet is treated as the unicast packet.

8. Protocol • The combinational media access protocol combines the unicast-based protocol and the Multicast Slot Reservation in the FT-TR architecture.

9. The Unicast-Based Protocol • Each node is assigned Ω slots per cycle and idle for the remaining N- Ω slots.

10. The Multicast Slot Reservation • IF M < Md, the MSR replicates the packet and transmits the replicated packets from the multicast source node to members of the multicast group individually. • IF M > Md, the MSR makes the reservation of the home channel of the multicast source node.

11. The Multicast Slot Reservation

12. Control Channel Access • Each node transmit a control packet via the round-robin TDMA.

13. The Arbitration Procedure • The request for multicast transmission has the higher priority to reserve the home channel and can be issued at any time slot. • The request for unicast transmission has the lower priority to reserve the channel and be issued according to the unicast protocol.

14. The combinational multicast schedule (CMS) • After receiving the control packet, all nodes execute the Combinational Multicast Schedule (CMS) at each time slot.

15. Simulation result • The parameters are N=50 network nodes , Ω= 25 wavelengths. • The buffer size of the dedicated queue per node is 100. • |G| and S are the normal distribution with mean of 5 nodes • The nodes in the multicast group G are randomly chosen from the uniform distribution [0,N-1]

16. Packet generation follows the Poisson arrival process with parameter q = 0.1. • The multicast packet with prob p and the unicast packet with prob 1-p • Md = 0 means the separate scheduling of unicast and multicast traffic. • Md = 100 means the scheduling of multicast traffic as unicast traffic.

17. Network throughput • The expected number of transmitted packets per time slot.

18. Packet delay • The number of time slots elapsed from the slot entering the network to the slot leaving the network.

19. Conclusions • Md needs to be analyzed in detail to optimize the performance of the protocol.

20. Reference • W. Y. Tseng and S. Y. Kuo, “A Combinational Media Access Protocol for Multicast Traffic in Single-Hop WDM LANS,” GLOBECOM’98 • W. Y. Tseng, C. C. Sue and S. Y. Kuo, “Performance Analysis for Unicast and Multicast Traffic in Broadcast-and-Select WDN Networks,” 1999