On-demand QoS routing

1. On-demand QoS routing 指導教授：石貴平 報告學生：莊宗翰 報告日期：2002/06/27

2. Outline • Introduction • Definition And Model • TDMA Channel Model • Time Slot Selection Lemma • Bandwidth Calculation • QoS Routing Protocol • Data Structure • Slots Selecting Method • Our Protocol

3. Introduction • An on-demand QoS routing protocol for ad hoc networks. • Assume a TDMA channel model within our network environment. • By recording only 1-hop neighbors' information in each host to avoid hidden-terminal and exposed-terminal problems for finding a bandwidth reservation route.

4. TDMA Channel Model TDMA Frame TDMA Frame The TDMA frame structure used in this paper. • Assume a simpler TDMA-based channel model. • Assume one single common channel shared by all hosts. • The channel is time-framed. Control Phase Data Phase Control Phase Data Phase Slot 1 Slot 2 Slot s

5. Time Slot Selection Lemma • Slot t is not yet scheduled to send or receive in neither sender nor receiver. • For any 1-hop neighbor host of sender, slot t is not scheduled to receive in it. • For any 1-hop neighbor host of receiver, slot t is not scheduled to send in it.

6. Bandwidth Calculation • BW(X, Y) = Free_Slots(X)∩Free_Slots(Y) ∩NNR_Slots(X)∩NNS_Slots(Y) • Free_Slots(host) • NNS_Slots(host) • NNR_Slots(host)

7. Bandwidth Calculation (Cont.) Free_Slots(A) = {0,1,4,5,8,9} Free_Slots(B) = {0,1,2,4,5,6,8} NNR_Slots(A) = {1,4,5,7,8} NNS_Slots(B) = {1,3,4,5} ∴ BW(A, B) = {0,1,4,5,8,9}∩{0,1,2,4,5,6,8}∩{1,4,5,7,8}∩{1,3,4,5} = {1,4,5}

8. Data Structure • Slots Information Table (SIT) • SITx [ 1…h , 1…s ] • RREQ(S, D, id, B, sender, route_path, next_hosts) • RREP(S, D, id, route_path) • route_path={ source, ( h1,s1 ), ( h2,s2 ), …, ( hi,si ) } • next_hosts={ ( h1,s1 ), ( h2,s2 ), …, ( hk,sk ) }

9. Our Protocol • Route Request • Destination • Route Reply

10. Route Request

11. Destination

12. Route Reply

13. Example

14. END