1. Computer Science and Engineering Parallel and Distributed Processing CSE 8380 January 25 2005 Session 4

2. Computer Science and Engineering Contents  Interconnection Networks  Static IN  Dynamic IN

3. Computer Science and Engineering Interconnection Network  Mode of Operation (Synchronous vs. Asynchronous)  Control Strategy (Centralized vs. Decentralized)  Switching Techniques (Packet switching vs. Circuit switching)  Topology (Static Vs. Dynamic)

4. Computer Science and Engineering Interconnection Network Taxonomy Interconnection Network Static Dynamic Bus-basedSwitch-based 1-D2-DHC SingleMultiple SSMS Crossbar

5. Computer Science and Engineering Static IN

6. Computer Science and Engineering Static Interconnection Networks  Static (fixed) interconnection networks are characterized by having fixed paths, unidirectional or bi-directional, between processors.  Completely connected networks (CCNs): Number of links: O(N 2 ), delay complexity: O(1).  Limited connected network (LCNs) Linear arrays Ring (Loop) networks Two-dimensional arrays Tree networks Cube network

7. Computer Science and Engineering Examples of Network Topology Linear Array Ring Mesh 63 12 54 Fully Connected

8. Computer Science and Engineering Hypercube d = 0d = 1d = 2d = 3 0 1 01 00 11 10 000 001 100110 111 011 101 010

9. Computer Science and Engineering Hypercube of dimension d n = 2 d d = log n Node degree = d Number of bits to label a node = d Diameter = d Number of edges = n*d/2 Hamming distance! Routing

10. Computer Science and Engineering Hypercubes 1110 1111 1010 1011 0110 0111 0010 0011 1101 1010 1000 1001 0100 0101 0010 0000 0001 S d = 4

11. Computer Science and Engineering Analysis and performance metrics static networks NetworkDegree(d)Diameter(D)CostSymmetryWorst delay CCNsN-11N(N-1)/2Yes1 Linear Array2N-1 NoN Binary Tree3 2(  log 2 N  –1) N-1Nolog 2 N n-cubelog 2 N nN/2Yeslog 2 N 2D-Mesh42(n-1)2(N-n)No NN K-ary n-cube2n n  k/2  nNYesK x log 2 N

12. Computer Science and Engineering Dynamic IN

13. Computer Science and Engineering Bus Based IN Global Memory P P C P C P C P P

14. Computer Science and Engineering Dynamic Interconnection Network Crossbar network An 8X8 Crossbar Network M1 M2 M3 M4 M5 M6 M7 M8 P1 P2 P3 P4 P5 P6 P7 P8

15. Computer Science and Engineering Dynamic Networks StraightExchange Upper-broadcast Lower-broadcast The different setting of the 2X2 SE

16. Computer Science and Engineering Multi-stage network 000 001 010 011 100 101 110 111 000 001 010 011 100 101 110 111

17. Computer Science and Engineering Dynamic Interconnection Network Multi-stage INs (MINs) An example 8X8 Shuffle-Exchange network (SEN). 000 001 010 011 100 101 110 111 000 001 010 011 100 101 110 111

18. Computer Science and Engineering Dynamic Interconnection Network Multi-stage INs (MINs) (cont.) An 8X8 Banyan network

19. Computer Science and Engineering Analysis and performance metrics dynamic networks NetworksDelayCostBlockin g Degree of FT BusO(N)O(1)Yes0 Multiple-busO(mN)O(m)Yes(m-1) MINsO(logN)O(NlogN)Yes0 CrossbarO(1)O(N 2 )No0