Replication in NileStore: (Record no. 8823)
[ view plain ]
| 000 -LEADER | |
|---|---|
| fixed length control field | 10188nam a22002537a 4500 |
| 008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION | |
| fixed length control field | 210112b2010 a|||f mb|| 00| 0 eng d |
| 040 ## - CATALOGING SOURCE | |
| Original cataloging agency | EG-CaNU |
| Transcribing agency | EG-CaNU |
| 041 0# - Language Code | |
| Language code of text | eng |
| Language code of abstract | eng |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 610 |
| 100 0# - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Ahmed Ali ElDin Mohamed Hassan |
| 245 1# - TITLE STATEMENT | |
| Title | Replication in NileStore: |
| Remainder of title | A Peer To Peer Global Storage System / |
| Statement of responsibility, etc. | Ahmed Ali ElDin Mohamed Hassan |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. | |
| Date of publication, distribution, etc. | 2010 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 116 p. |
| Other physical details | ill. |
| Dimensions | 21 cm. |
| 500 ## - GENERAL NOTE | |
| Materials specified | Supervisor: Nael Osman |
| 502 ## - Dissertation Note | |
| Dissertation type | Thesis (M.A.)—Nile University, Egypt, 2010 . |
| 504 ## - Bibliography | |
| Bibliography | "Includes bibliographical references" |
| 505 0# - Contents | |
| Formatted contents note | Contents:<br/>Chapter<br/>1 Thesis outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1<br/>1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1<br/>1.2 Contribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2<br/>1.3 Thesis organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3<br/>2 An overview of distributed storage systems . . . . . . . . . . . . . . . . . . . . . 4<br/>2.1 Examples of distributed storage systems . . . . . . . . . . . . . . . . . . . 5<br/>2.1.1 The Farsite project . . . . . . . . . . . . . . . . . . . . . . . . . . . 6<br/>2.1.1.1 Feasability of a distributed storage system . . . . . . . . . 6<br/>2.1.1.2 Network problem not storage problem . . . . . . . . . . . 6<br/>2.1.2 The OceanStore project . . . . . . . . . . . . . . . . . . . . . . . . 8<br/>2.1.2.1 Thermodynamical approach . . . . . . . . . . . . . . . . . 8<br/>2.1.2.2 Using Tapestry DHT . . . . . . . . . . . . . . . . . . . . . 9<br/>2.1.2.3 Tackling versioning of mutable files . . . . . . . . . . . . . 11<br/>2.1.3 The Tahoe project . . . . . . . . . . . . . . . . . . . . . . . . . . . 12<br/>2.1.3.1 Tahoe security explained . . . . . . . . . . . . . . . . . . . 12<br/>2.1.3.2 Technologies used and system architecture . . . . . . . . 14<br/>2.1.4 The GEMS project . . . . . . . . . . . . . . . . . . . . . . . . . . . 16<br/>2.1.4.1 A Global Storage for Academic Simulations . . . . . . . . 16<br/>2.1.4.2 Replica Management as a Linear Control Problem . . . . 17<br/>2.2 The availability and durability problem . . . . . . . . . . . . . . . . . . . 18<br/>2.2.1 Replica types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19<br/>2.2.2 Replica placement strategies and algorithms . . . . . . . . . . . . . 19<br/>2.2.2.1 Use Of AI hill-climbing algorithms . . . . . . . . . . . . . 20<br/>2.2.2.2 Lazy Repair and Reintegration . . . . . . . . . . . . . . . 20<br/>2.2.2.3 Using Age Estimation For Placement . . . . . . . . . . . 22<br/>2.2.2.4 Proactive replication . . . . . . . . . . . . . . . . . . . . . 25<br/>2.2.2.5 Gossiping is Practical . . . . . . . . . . . . . . . . . . . . 25<br/>2.3 Security in distributed storage systems . . . . . . . . . . . . . . . . . . . . 26<br/>2.3.1 The Sybil attack . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26<br/>2.4 Incentives to use online storage systems . . . . . . . . . . . . . . . . . . . . 29<br/>vii<br/>2.4.1 Replica placement as a game . . . . . . . . . . . . . . . . . . . . . . 29<br/>2.5 Measurements and models of distributed systems . . . . . . . . . . . . . . 30<br/>2.5.1 Analysis of deployed P2P systems . . . . . . . . . . . . . . . . . . . 30<br/>2.5.1.1 KAD network analysis . . . . . . . . . . . . . . . . . . . . 30<br/>2.5.1.2 Availability analysis in Overnet . . . . . . . . . . . . . . . 31<br/>2.5.1.3 Comparing different systems . . . . . . . . . . . . . . . . . 32<br/>2.5.2 Modeling of distributed storage systems . . . . . . . . . . . . . . . 33<br/>2.5.2.1 Failure Correlation Analysis . . . . . . . . . . . . . . . . . 33<br/>2.5.2.2 Effect of environment on churn . . . . . . . . . . . . . . . 36<br/>2.5.2.3 Redundancy Vs Scaling Vs Dynamical System . . . . . . . 38<br/>2.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39<br/>3 Validation of a Hybrid Replication Algorithm . . . . . . . . . . . . . . . . . . . 41<br/>3.1 Why use an adaptive hybrid replication scheme? . . . . . . . . . . . . . . . 41<br/>3.2 Modeling the distributed storage problem . . . . . . . . . . . . . . . . . . . 42<br/>3.2.1 System assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . 42<br/>3.2.2 Peers’ model description . . . . . . . . . . . . . . . . . . . . . . . . 43<br/>3.2.3 The system model . . . . . . . . . . . . . . . . . . . . . . . . . . . 43<br/>3.3 Replication as an adaptive control problem . . . . . . . . . . . . . . . . . . 45<br/>3.3.1 The estimator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45<br/>3.4 Building an adaptive controller . . . . . . . . . . . . . . . . . . . . . . . . 46<br/>3.5 Choosing T: the time between two estimations of the churn . . . . . . . 46<br/>3.6 Validating the algorithm using simulation . . . . . . . . . . . . . . . . . . . 47<br/>3.7 Critique for this algorithm . . . . . . . . . . . . . . . . . . . . . . . . . . . 49<br/>4 NileStore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51<br/>4.1 A framework for replica placement . . . . . . . . . . . . . . . . . . . . . . 51<br/>4.2 Nomenclature and Notations . . . . . . . . . . . . . . . . . . . . . . . . . . 52<br/>4.3 NileStore system: Introduction and Design goals . . . . . . . . . . . . . . 53<br/>4.3.1 System Design Goals . . . . . . . . . . . . . . . . . . . . . . . . . . 53<br/>4.4 NileStore: The protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56<br/>4.4.1 The Tracker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56<br/>4.4.2 The peers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59<br/>4.5 From Replica Placement to Task Assignment . . . . . . . . . . . . . . . . . 61<br/>4.5.1 Transform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61<br/>4.5.2 Profit functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63<br/>4.5.2.1 Family 1: Profit function I . . . . . . . . . . . . . . . . . . 64<br/>4.5.2.2 FAmily 1: Profit function II . . . . . . . . . . . . . . . . . 66<br/>4.5.2.3 Family 1:Profit function III . . . . . . . . . . . . . . . . . 67<br/>4.5.2.4 Family 1:Profit function IV . . . . . . . . . . . . . . . . . 68<br/>4.5.2.5 Family 2:Profit function V . . . . . . . . . . . . . . . . . . 69<br/>4.5.3 Solving the problem . . . . . . . . . . . . . . . . . . . . . . . . . . 70<br/>5 Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71<br/>5.1 Discrete Event Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 71<br/>viii<br/>5.1.1 Discrete Event Simulation Anatomy . . . . . . . . . . . . . . . . . . 72<br/>5.1.1.1 Workload Modeling . . . . . . . . . . . . . . . . . . . . . . 72<br/>5.1.1.2 Service Disciplines . . . . . . . . . . . . . . . . . . . . . . 72<br/>5.1.1.3 Accuracy Vs Cost . . . . . . . . . . . . . . . . . . . . . . 73<br/>5.1.2 Network Simulation: Practical design . . . . . . . . . . . . . . . . . 73<br/>5.2 Simulating NileStore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74<br/>5.2.1 NileStore’s Simulator Anatomy . . . . . . . . . . . . . . . . . . . . 74<br/>5.2.2 NileStore’s Workload modeling . . . . . . . . . . . . . . . . . . . . 74<br/>5.2.2.1 Peers’ Upload and Download Rates . . . . . . . . . . . . . 75<br/>5.2.2.2 Storage Model . . . . . . . . . . . . . . . . . . . . . . . . 75<br/>5.2.2.3 Leave/Join Rates . . . . . . . . . . . . . . . . . . . . . . . 76<br/>5.2.3 NileStore’s Simulator Practical Design . . . . . . . . . . . . . . . . 77<br/>5.2.3.1 Classes for Managing the Queue . . . . . . . . . . . . . . 77<br/>5.2.3.2 Networking Classes . . . . . . . . . . . . . . . . . . . . . . 78<br/>5.2.3.3 NileStore’s Classes . . . . . . . . . . . . . . . . . . . . . . 79<br/>5.2.3.4 The Main Loop . . . . . . . . . . . . . . . . . . . . . . . . 80<br/>6 Experiments and Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81<br/>6.1 NileStore’s Performance with time . . . . . . . . . . . . . . . . . . . . . . . 81<br/>6.1.1 Experiment conditions . . . . . . . . . . . . . . . . . . . . . . . . . 81<br/>6.1.2 Experiment results . . . . . . . . . . . . . . . . . . . . . . . . . . . 83<br/>6.1.2.1 Reason for the poor performance of profit function V . . . 83<br/>6.1.2.2 Family 1 profit functions are similar . . . . . . . . . . . . 83<br/>6.1.3 Changing the experiment conditions . . . . . . . . . . . . . . . . . 87<br/>6.2 Effect of changing the churn rate . . . . . . . . . . . . . . . . . . . . . . . 89<br/>6.3 Effect of changing τ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93<br/>6.4 Effect of changing r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94<br/>6.5 Time taken for replica placement . . . . . . . . . . . . . . . . . . . . . . . 95<br/>7 Conclusion and Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97<br/>7.1 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99<br/>References . . . . . . . . |
| 520 3# - Abstract | |
| Abstract | Abstract:<br/>Replica placement algorithms in distributed storage and backup systems have a direct effect<br/>on the required time for replication, the availability and durability of files and the latency<br/>of file retrieval. In this work we introduce Nilestore, a P2P-assisted cloud storage protocol<br/>that transforms the replica placement problem into a linear task assignment optimization<br/>problem. The task assignment problem is solved using an optimization engine. The assignment<br/>takes into account each peer’s upload bandwidth, download bandwidth, contributed<br/>free storage and the size of data that it needs to replicate. The task assignment is solved<br/>using a suboptimal optimization algorithm for speed. This approach to solving the replica<br/>placement problem has not been taken before for online storage systems. We show our<br/>simulation results for the algorithms under realistic network conditions that were obtained<br/>from many studies conducted on P2P networks and distributed storage. Our results show<br/>that using NileStore can offload the storage servers of the cloud by more than 75% using<br/>the available replicas in the system. |
| 546 ## - Language Note | |
| Language Note | Text in English, abstracts in English. |
| 650 #4 - Subject | |
| Subject | Informatics-IFM |
| 655 #7 - Index Term-Genre/Form | |
| Source of term | NULIB |
| focus term | Dissertation, Academic |
| 690 ## - Subject | |
| School | Informatics-IFM |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | Dewey Decimal Classification |
| Koha item type | Thesis |
| 650 #4 - Subject | |
| -- | 266 |
| 655 #7 - Index Term-Genre/Form | |
| -- | 187 |
| 690 ## - Subject | |
| -- | 266 |
| Withdrawn status | Lost status | Source of classification or shelving scheme | Damaged status | Not for loan | Home library | Current library | Date acquired | Total Checkouts | Full call number | Date last seen | Price effective from | Koha item type |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dewey Decimal Classification | Not For Loan | Main library | Main library | 01/12/2021 | 610 / AH.R 2010 | 01/12/2021 | 01/12/2021 | Thesis |