3.6.2.1 VC Allocator............................................................ 66

3.6.2.2 Switch Allocator ..................................................... 69

3.7 Adaptive Router Architecture Design ............................................. 70

3.8 Summary.............................................................................................. 73

References ....................................................................................................... 73

4. Evaluation of Network-on-Chip Architectures...................................... 75

4.1 Evaluation Methodologies of NoC ................................................... 75

4.1.1 Performance Metrics ............................................................. 78

4.1.2 Cost Metrics ............................................................................80

4.2 Traffic Modeling .................................................................................. 81

4.3 Selection of Channel Width and Flit Size........................................84

4.4 Simulation Results and Analysis of MoT Network
with WH Router ..................................................................................84

4.4.1 Accepted Traffic versus Offered Load ................................85

4.4.2 Throughput versus Locality Factor.....................................85

4.4.3 Average Overall Latency at Different Locality Factors .... 86

4.4.4 Energy Consumption at Different Locality Factors.......... 88

4.5 Impact of FIFO Size and Placement in Energy and
Performance of a Network.................................................................90

4.6 Performance and Cost Comparison of MoT with Other NoC
Structures Having WH Router under Self-Similar Traffic............ 93

4.6.1 Network Area Estimation..................................................... 94

4.6.2 Network Aspect Ratio ........................................................... 96

4.6.3 Performance Comparison..................................................... 97

4.6.3.1 Accepted Traffic versus Offered Load................. 97

4.6.3.2 Throughput versus Locality Factor ..................... 98

4.6.3.3 Average Overall Latency under
Localized Traffic .................................................. 99

4.6.4 Comparison of Energy Consumption............................... 102

4.7 Simulation Results and Analysis of MoT
Network with Virtual Channel Router.......................................... 103

4.7.1 Throughput versus Offered Load ..................................... 104

4.7.2 Latency versus Offered Load ............................................. 104

4.7.3 Energy Consumption .......................................................... 105

4.7.4 Area Required ...................................................................... 108

4.8 Performance and Cost Comparison of MoT with Other
NoC Structures Having VC Router ................................................ 109

4.8.1 Accepted Traffic versus Offered Load .............................. 109

4.8.2 Throughput versus Locality Factor................................... 109

4.8.3 Average Overall Latency under Localized Traffic .......... 110

4.8.4 Energy Consumption .......................................................... 111

4.8.5 Area Overhead ..................................................................... 113

4.9 Limitations of Tree-Based Topologies............................................ 114

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Contents