Davide Cherubini - PhD Thesis - UniCA Eprints

More documents

Recommendations

Info

Chapter 8ConclusionsOptimization problems in telecommunication have been widely studied, mainlyfocusing the improvement of traffic routing within the network.On the other hand, methods to successfully deliver flows in case of failure havebeen slightly explored. I have presented three linear models that cover this lackusing technological and topological constraints derived from the observation ofreal-world telecommunication networks.In particular, the models use an optimal (or suboptimal) configuration of IGP protocolparameters as underlying condition and take advantages carried by TrafficEngineering MPLS techniques in order to find a survivable global configuration.The main goals achieved in this dissertation can be summarized as follows:• optimal configuration in normal working condition, solving the GeneralRouting Problem in a network using IS-IS with complementary MPLS LSPs.• optimal configuration under single link failure condition using IS-IS andMPLS LSPs.• results shown that network operators presence is minimal and is only requestedin the preliminary configuration. Survivability of the service deliveryis guaranteed automatically.• the rule of the “60%” has been revisedThe empiric rule of “60%” states that an upgrade of the network is neededif the link occupation is greater than 60% of its capacity. I have shown that an83
optimal configuration of network parameters, pull down the utilization of the linkwith respect to the usual configuration made by network operators based on theirexperience. This result becomes relevant in economic terms because it reduces,and shifts in time, the investments required to upgrade the network.Furthermore, the LP models are able to determine the optimal configurationin nearly real time, while the optimization processes based on heuristic techniquesrequire numerous hours in order to find a feasible solution. Finally, my work hasproduced a traffic collector/analyzer/monitor tool that is currently used by animportant Italian ISP (Tiscali).84
Page 4 and 5:
AcknowledgementsThis dissertation w
Page 6 and 7:
AbstractThis dissertation investiga
Page 9 and 10:
CONTENTS7.4 The Real ISP’s Italia
Page 11 and 12:
LIST OF FIGURES7.3 Default metrics
Page 13 and 14:
1.2 Objectives of the dissertation2
Page 15 and 16:
Chapter 2Basic knowledgeThis chapte
Page 17 and 18:
2.1 Understanding IS-IS• A = sour
Page 19 and 20:
2.2 Understanding MPLS Technology2.
Page 21 and 22:
2.2 Understanding MPLS TechnologyTh
Page 23 and 24:
2.4 Restoration SchemesHowever, fai
Page 26 and 27:
3.1 Optimization of IS-IS/OSPF rout
Page 28:
3.3 Survivability problemhas been d
Page 31 and 32:
4.1 Heuristic Algorithmsmeta-heuris
Page 33 and 34:
4.1 Heuristic Algorithmsto keep a c
Page 35 and 36:
4.1 Heuristic Algorithmsprobability
Page 37 and 38:
4.3 Linear Programming ApproachExam
Page 39 and 40:
5.2 Traffic monitoring• 60% of th
Page 41 and 42:
5.2 Traffic monitoringExporting the
Page 43 and 44: 5.2 Traffic monitoringare included
Page 45 and 46: 5.2 Traffic monitoringthe Internet.
Page 47 and 48: 5.2 Traffic monitoring5.2.3 The net
Page 49 and 50: 5.2 Traffic monitoring5.2.4 Monitor
Page 51 and 52: 5.2 Traffic monitoringFigure 5.9: S
Page 53 and 54: Chapter 6LP Optimization ModelsThis
Page 55 and 56: 6.2 Graphs and Network Flowswith a
Page 57 and 58: 6.2 Graphs and Network FlowsWhere B
Page 59 and 60: 6.2 Graphs and Network Flows6.2.3 T
Page 61 and 62: 6.3 Multicommodity Flow Problemscom
Page 63 and 64: 6.4 LP modelsThe second layer intro
Page 65 and 66: 6.4 LP modelsEquation 6.32 is the o
Page 67 and 68: 6.4 LP modelsmalized as follows:z =
Page 69 and 70: 6.4 LP models(a) Rerouting flow p
Page 71 and 72: 6.4 LP models(a) 1 st solution(b) 2
Page 73 and 74: 6.4 LP models∑f∈Fx f,lij⎛⎝i
Page 75 and 76: 6.4 LP modelsterm is the MPLS part
Page 77 and 78: 7.2 The highly meshed network7.2 Th
Page 79 and 80: 7.3 The IBCN European network7.3 Th
Page 81 and 82: 7.3 The IBCN European networkmaximu
Page 83 and 84: 7.3 The IBCN European networkSurviv
Page 85 and 86: 7.3 The IBCN European networkFigure
Page 87 and 88: 7.4 The Real ISP’s Italian Backbo
Page 93: 7.5 Conclusion and validation of re
Page 97 and 98: REFERENCES[14] Jones Lustig Format
Page 99 and 100: REFERENCES[40] A. V. Fiacco and G.
Page 101: REFERENCES[61] A. Nucci, B. Schroed
show all

Davide Cherubini - PhD Thesis - UniCA Eprints

Create successful ePaper yourself

Delete template?

Save as template?