Disclaimer: I will rework this. I had too much to say and had to cut to fit in 40mn. Actually I spoke so fast that I spent only 20. So I will add some content soon.
Abstract:
In the good ol' times, when Computer Science was young and open like the ocean, brave captains were more mathematicians than developers. Also, they had great beards.
They opened routes, fought monsters, discovered unknown lands, and we had fun on this ever since. As time goes by, we seem to forget some of their warnings and wisdom.
It's time to roll the treasure map and find the buried chests of pure gold advice!
The computer science behind a modern disributed data storeJ On The Beach
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Every application needs a stateful layer which holds the data. There are at least three necessary components which are everything else than trivial to combine, and, of course, even more challenging when heading for an acceptable performance.
Over the past years there has been significant progress in both the science and practical implementations of such data stores. In his talk Max Neunhoeffer will introduce the audience to some of the needed ingredients, address the difficulties of their interplay and show four modern approaches of distributed open-source data stores (ArangoDB, Cassandra, Cockroach and RethinkDB).
The Computer Science Behind a modern Distributed DatabaseArangoDB Database
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Every application needs a stateful layer which holds the data. There are several different necessary components which are anything but trivial to combine, and, of course, even more challenging when attempting to optimize for performance. Over the past years there has been significant progress in both the science and practical implementations of such data stores. In this talk Dan Larkin-York will introduce the audience to some of the challenges, address the difficulties of their interplay, and cover key approaches taken by some of the industry’s leaders (ArangoDB, Cassandra, CockroachDB, MarkLogic, and more).
OSDC 2018 | The Computer science behind a modern distributed data store by Ma...NETWAYS
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Most applications need a stateful layer which holds the data. There are at least three necessary ingredients which are everything else than trivial to combine and of course even more challenging when heading for an acceptable performance. Over the past years there has been significant progress in respect in both the science and practical implementations of such data stores. In his talk Max Neunhoeffer will introduce the audience to some of the needed ingredients, address the difficulties of their interplay and show four modern approaches of distributed open-source data stores.
Topics are:
– Challenges in developing a distributed, resilient data store
– Consensus, distributed transactions, distributed query optimization and execution
– The inner workings of ArangoDB, Cassandra, Cockroach and RethinkDB
The talk will touch complex and difficult computer science, but will at the same time be accessible to and enjoyable by a wide range of developers.
The large-scale cyberinformatics method to replication is defined not only by the analysis of local-area networks, but also by the structured need for the Internet. Here, we confirm the refinement of superpages, which embodies the unfortunate principles of operating systems. SHODE, our new methodology for secure methodologies, is the solution to all of these obstacles.
The computer science behind a modern disributed data storeJ On The Beach
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Every application needs a stateful layer which holds the data. There are at least three necessary components which are everything else than trivial to combine, and, of course, even more challenging when heading for an acceptable performance.
Over the past years there has been significant progress in both the science and practical implementations of such data stores. In his talk Max Neunhoeffer will introduce the audience to some of the needed ingredients, address the difficulties of their interplay and show four modern approaches of distributed open-source data stores (ArangoDB, Cassandra, Cockroach and RethinkDB).
The Computer Science Behind a modern Distributed DatabaseArangoDB Database
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Every application needs a stateful layer which holds the data. There are several different necessary components which are anything but trivial to combine, and, of course, even more challenging when attempting to optimize for performance. Over the past years there has been significant progress in both the science and practical implementations of such data stores. In this talk Dan Larkin-York will introduce the audience to some of the challenges, address the difficulties of their interplay, and cover key approaches taken by some of the industry’s leaders (ArangoDB, Cassandra, CockroachDB, MarkLogic, and more).
OSDC 2018 | The Computer science behind a modern distributed data store by Ma...NETWAYS
What we see in the modern data store world is a race between different approaches to achieve a distributed and resilient storage of data. Most applications need a stateful layer which holds the data. There are at least three necessary ingredients which are everything else than trivial to combine and of course even more challenging when heading for an acceptable performance. Over the past years there has been significant progress in respect in both the science and practical implementations of such data stores. In his talk Max Neunhoeffer will introduce the audience to some of the needed ingredients, address the difficulties of their interplay and show four modern approaches of distributed open-source data stores.
Topics are:
– Challenges in developing a distributed, resilient data store
– Consensus, distributed transactions, distributed query optimization and execution
– The inner workings of ArangoDB, Cassandra, Cockroach and RethinkDB
The talk will touch complex and difficult computer science, but will at the same time be accessible to and enjoyable by a wide range of developers.
The large-scale cyberinformatics method to replication is defined not only by the analysis of local-area networks, but also by the structured need for the Internet. Here, we confirm the refinement of superpages, which embodies the unfortunate principles of operating systems. SHODE, our new methodology for secure methodologies, is the solution to all of these obstacles.
Constructing Operating Systems and E-CommerceIJARIIT
Information retrieval systems and the partition table, while essential in theory, have not until recently been considered important [15]. In fact, few theorists would disagree with the deployment of massive multiplayer online role-playing games, which embodies the robust principles of complexity theory. In this work we investigate how Smalltalk can be applied to the synthesis of lambda calculus.
Data Structures in the Multicore Age : NotesSubhajit Sahu
Highlighted notes of article while studying Concurrent Data Structures, CSE:
Data Structures in the Multicore Age
Nir Shivit
Communications of the ACM, March 2011, Vol. 54 No. 3, Pages 76-84
10.1145/1897852.1897873
Nir Shavit is a professor of computer science at Tel-Aviv
University and a member of the Scalable Synchronization
Group at Oracle Labs. He is a recipient of the 2004 ACM/
EATCS Gödel Prize.
Parallel and distributed genetic algorithm with multiple objectives to impro...khalil IBRAHIM
we argue that the timetabling problem reflects the problem of scheduling university courses, So you must specify the range of time periods and a group of instructors for a range of lectures to check a set of constraints and reduce the cost of other constraints ,this is the problem called NP-hard, it is a class of problems that are informally, it’s mean that necessary operations to solve the problem will increase exponentially and directly proportional to the size of the problem, The construction of timetable is the most complicated problem that was facing many universities, and increased by size of the university data and overlapping disciplines between colleges, and when a traditional algorithm (EA) is unable to provide satisfactory results, a distributed EA (dEA), which deploys the population on distributed systems, it also offers an opportunity to solve extremely high dimensional problems through distributed coevolution using a divide-and-conquer mechanism, Further, the distributed environment allows a dEA to maintain population diversity, thereby avoiding local optima and also facilitating multi-objective search, by employing different distribution models to parallelize the processing of EAs, we designed a genetic algorithm suitable for Universities environment and the constraints facing it when building timetable for lectures.
All new computers have multicore processors. To exploit this hardware parallelism for improved
performance, the predominant approach today is multithreading using shared variables and locks. This
approach has potential data races that can create a nondeterministic program. This paper presents a
promising new approach to parallel programming that is both lock-free and deterministic. The standard
forall primitive for parallel execution of for-loop iterations is extended into a more highly structured
primitive called a Parallel Operation (POP). Each parallel process created by a POP may read shared
variables (or shared collections) freely. Shared collections modified by a POP must be selected from a
special set of predefined Parallel Access Collections (PAC). Each PAC has several Write Modes that
govern parallel updates in a deterministic way. This paper presents an overview of a Prototype Library
that implements this POP-PAC approach for the C++ language, including performance results for two
benchmark parallel programs.
All new computers have multicore processors. To exploit this hardware parallelism for improved
perf
ormance, the predominant approach today is multithreading using shared variables and locks. This
approach has potential data races that can create a nondeterministic program. This paper presents a
promising new approach to parallel programming that is both
lock
-
free and deterministic. The standard
forall primitive for parallel execution of for
-
loop iterations is extended into a more highly structured
primitive called a Parallel Operation (POP). Each parallel process created by a POP may read shared
variable
s (or shared collections) freely. Shared collections modified by a POP must be selected from a
special set of predefined Parallel Access Collections (PAC). Each PAC has several Write Modes that
govern parallel updates in a deterministic way. This paper pre
sents an overview of a Prototype Library
that implements this POP
-
PAC approach for the C++ language, including performance results for two
benchmark parallel programs.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Comparing reinforcement learning and access points with rowelijcseit
Due to the fast development of the Cloud Computing technologies, the rapid increase of cloud services
are became very remarkable. The fact of integration of these services with many of the modern
enterprises cannot be ignored. Microsoft, Google, Amazon, SalesForce.com and the other leading IT
companies are entered the field of developing these services. This paper presents a comprehensive survey
of current cloud services, which are divided into eleven categories. Also the most famous providers for
these services are listed. Finally, the Deployment Models of Cloud Computing are mentioned and briefly
discussed.
Highlighted notes of article while studying Concurrent Data Structures, CSE:
Real-world Concurrency
Bryan Cantrill and Jeff Bonwick,
Sun Microsystems
ACM Queue, September 2008 https://doi.org/10.1145/1454456.1454462
BRYAN CANTRILL is a Distinguished Engineer at Sun Microsystems, where he has worked on concurrent systems since coming to Sun to work with Jeff Bonwick on Solaris performance in 1996. Along with colleagues Mike Shapiro and Adam Leventhal, Cantrill developed DTrace, a facility for dynamic instrumentation of production systems that was directly inspired by his frustration in understanding the behavior of concurrent systems.
JEFF BONWICK is a Fellow at Sun Microsystems, where he has worked on concurrent systems since 1990. He is best known for inventing and leading the development of Sun’s ZFS (Zettabyte File System), but prior to this he was known for having written (or rather, rewritten) many of the most parallel subsystems in the Solaris kernel, including the syn- chronization primitives, the kernel memory allocator, and the thread-blocking mechanism.
https://dl.acm.org/doi/10.1145/1454456.1454462
Discussion Board
Deliverable Length: 4 – 6 paragraphs
An organization has a number of tools available when determining how best to address performance issues on their network. The organization can use subnetting or they can use segmentation.
Discuss the pros and cons of each.
Provide examples of when each would be appropriate.
Individual Project
Deliverable Length: 4 – 5 pages
The OSI Layer 3 (Network Layer) is one of the layers that perform packet segmentation. The OSI Layer 3 is roughly equivalent to the Internet Layer of the TCP/IP model and the Layer 4 (Transport Layer) of the OSI model is roughly equivalent to the Host-to-Host layer of the TCP/IP model. The above two layers perform network segmentation. Based on the above information, answer the following questions.
(a) Describe in detail how packets are segmented by the Host-to-host layer (Transport Layer) Internet Layer of the TCP/IP model.
(b) Do all packets arrive at their destination in the order in which they were segmented and transmitted? Why or why not?
(c) Describe how segmented packets are re-arranged or reassembled at the packets’ destination to ensure that received segmented packets match the order in which they were segmented and transmitted.
(d) How are errors handled during transmission of segmented packets?
(e) What's the difference between a TCP segment and a TCP packet?
Please answer the following questions and requirements to write your paper of 4–5 pages. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
Please include the following elements in your paper:
A title page
A report that includes the following:
An introduction to the contents of the report
Detailed explanations about the items listed regarding network segmentation, error handling, TCP segments and TCP packets.
Please cite your references in APA format.
Weeks 3 and 4
Individual Project :
Deliverable Length : 3-5 pages
Please answer the following questions and requirements to write your 3–5 page paper. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
The following is a case study about a design company.
You are a senior network administrator for a networking solutions firm. Years ago, you installed a small LAN at a design company. It is growing fast and needs your networking solutions firm to upgrade its network. You assigned Liz to the job. That afternoon, while preparing to work on a lab ass.
Discussion Board
Deliverable Length: 4 – 6 paragraphs
An organization has a number of tools available when determining how best to address performance issues on their network. The organization can use subnetting or they can use segmentation.
Discuss the pros and cons of each.
Provide examples of when each would be appropriate.
Individual Project
Deliverable Length: 4 – 5 pages
The OSI Layer 3 (Network Layer) is one of the layers that perform packet segmentation. The OSI Layer 3 is roughly equivalent to the Internet Layer of the TCP/IP model and the Layer 4 (Transport Layer) of the OSI model is roughly equivalent to the Host-to-Host layer of the TCP/IP model. The above two layers perform network segmentation. Based on the above information, answer the following questions.
(a) Describe in detail how packets are segmented by the Host-to-host layer (Transport Layer) Internet Layer of the TCP/IP model.
(b) Do all packets arrive at their destination in the order in which they were segmented and transmitted? Why or why not?
(c) Describe how segmented packets are re-arranged or reassembled at the packets’ destination to ensure that received segmented packets match the order in which they were segmented and transmitted.
(d) How are errors handled during transmission of segmented packets?
(e) What's the difference between a TCP segment and a TCP packet?
Please answer the following questions and requirements to write your paper of 4–5 pages. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
Please include the following elements in your paper:
A title page
A report that includes the following:
An introduction to the contents of the report
Detailed explanations about the items listed regarding network segmentation, error handling, TCP segments and TCP packets.
Please cite your references in APA format.
Weeks 3 and 4
Individual Project :
Deliverable Length : 3-5 pages
Please answer the following questions and requirements to write your 3–5 page paper. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
The following is a case study about a design company.
You are a senior network administrator for a networking solutions firm. Years ago, you installed a small LAN at a design company. It is growing fast and needs your networking solutions firm to upgrade its network. You assigned Liz to the job. That afternoon, while preparing to work on a lab ass.
Event-Driven, Client-Server Archetypes for E-Commerceijtsrd
The networking solution to symmetric encryption [1] is defined not only by the understanding of write-ahead logging, but also by the extensive need for neural networks. In this position paper, we verify the visualization of red-black trees. In this paper we concentrate our efforts on arguing that local-area networks can be made wireless, authenticated, and Bayesian [2]. Chirag Patel"Event-Driven, Client-Server Archetypes for E-Commerce" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-1 , December 2016, URL: http://www.ijtsrd.com/papers/ijtsrd56.pdf http://www.ijtsrd.com/engineering/computer-engineering/56/event-driven-client-server-archetypes-for-e-commerce/chirag-patel
Constructing Operating Systems and E-CommerceIJARIIT
Information retrieval systems and the partition table, while essential in theory, have not until recently been considered important [15]. In fact, few theorists would disagree with the deployment of massive multiplayer online role-playing games, which embodies the robust principles of complexity theory. In this work we investigate how Smalltalk can be applied to the synthesis of lambda calculus.
Data Structures in the Multicore Age : NotesSubhajit Sahu
Highlighted notes of article while studying Concurrent Data Structures, CSE:
Data Structures in the Multicore Age
Nir Shivit
Communications of the ACM, March 2011, Vol. 54 No. 3, Pages 76-84
10.1145/1897852.1897873
Nir Shavit is a professor of computer science at Tel-Aviv
University and a member of the Scalable Synchronization
Group at Oracle Labs. He is a recipient of the 2004 ACM/
EATCS Gödel Prize.
Parallel and distributed genetic algorithm with multiple objectives to impro...khalil IBRAHIM
we argue that the timetabling problem reflects the problem of scheduling university courses, So you must specify the range of time periods and a group of instructors for a range of lectures to check a set of constraints and reduce the cost of other constraints ,this is the problem called NP-hard, it is a class of problems that are informally, it’s mean that necessary operations to solve the problem will increase exponentially and directly proportional to the size of the problem, The construction of timetable is the most complicated problem that was facing many universities, and increased by size of the university data and overlapping disciplines between colleges, and when a traditional algorithm (EA) is unable to provide satisfactory results, a distributed EA (dEA), which deploys the population on distributed systems, it also offers an opportunity to solve extremely high dimensional problems through distributed coevolution using a divide-and-conquer mechanism, Further, the distributed environment allows a dEA to maintain population diversity, thereby avoiding local optima and also facilitating multi-objective search, by employing different distribution models to parallelize the processing of EAs, we designed a genetic algorithm suitable for Universities environment and the constraints facing it when building timetable for lectures.
All new computers have multicore processors. To exploit this hardware parallelism for improved
performance, the predominant approach today is multithreading using shared variables and locks. This
approach has potential data races that can create a nondeterministic program. This paper presents a
promising new approach to parallel programming that is both lock-free and deterministic. The standard
forall primitive for parallel execution of for-loop iterations is extended into a more highly structured
primitive called a Parallel Operation (POP). Each parallel process created by a POP may read shared
variables (or shared collections) freely. Shared collections modified by a POP must be selected from a
special set of predefined Parallel Access Collections (PAC). Each PAC has several Write Modes that
govern parallel updates in a deterministic way. This paper presents an overview of a Prototype Library
that implements this POP-PAC approach for the C++ language, including performance results for two
benchmark parallel programs.
All new computers have multicore processors. To exploit this hardware parallelism for improved
perf
ormance, the predominant approach today is multithreading using shared variables and locks. This
approach has potential data races that can create a nondeterministic program. This paper presents a
promising new approach to parallel programming that is both
lock
-
free and deterministic. The standard
forall primitive for parallel execution of for
-
loop iterations is extended into a more highly structured
primitive called a Parallel Operation (POP). Each parallel process created by a POP may read shared
variable
s (or shared collections) freely. Shared collections modified by a POP must be selected from a
special set of predefined Parallel Access Collections (PAC). Each PAC has several Write Modes that
govern parallel updates in a deterministic way. This paper pre
sents an overview of a Prototype Library
that implements this POP
-
PAC approach for the C++ language, including performance results for two
benchmark parallel programs.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Comparing reinforcement learning and access points with rowelijcseit
Due to the fast development of the Cloud Computing technologies, the rapid increase of cloud services
are became very remarkable. The fact of integration of these services with many of the modern
enterprises cannot be ignored. Microsoft, Google, Amazon, SalesForce.com and the other leading IT
companies are entered the field of developing these services. This paper presents a comprehensive survey
of current cloud services, which are divided into eleven categories. Also the most famous providers for
these services are listed. Finally, the Deployment Models of Cloud Computing are mentioned and briefly
discussed.
Highlighted notes of article while studying Concurrent Data Structures, CSE:
Real-world Concurrency
Bryan Cantrill and Jeff Bonwick,
Sun Microsystems
ACM Queue, September 2008 https://doi.org/10.1145/1454456.1454462
BRYAN CANTRILL is a Distinguished Engineer at Sun Microsystems, where he has worked on concurrent systems since coming to Sun to work with Jeff Bonwick on Solaris performance in 1996. Along with colleagues Mike Shapiro and Adam Leventhal, Cantrill developed DTrace, a facility for dynamic instrumentation of production systems that was directly inspired by his frustration in understanding the behavior of concurrent systems.
JEFF BONWICK is a Fellow at Sun Microsystems, where he has worked on concurrent systems since 1990. He is best known for inventing and leading the development of Sun’s ZFS (Zettabyte File System), but prior to this he was known for having written (or rather, rewritten) many of the most parallel subsystems in the Solaris kernel, including the syn- chronization primitives, the kernel memory allocator, and the thread-blocking mechanism.
https://dl.acm.org/doi/10.1145/1454456.1454462
Discussion Board
Deliverable Length: 4 – 6 paragraphs
An organization has a number of tools available when determining how best to address performance issues on their network. The organization can use subnetting or they can use segmentation.
Discuss the pros and cons of each.
Provide examples of when each would be appropriate.
Individual Project
Deliverable Length: 4 – 5 pages
The OSI Layer 3 (Network Layer) is one of the layers that perform packet segmentation. The OSI Layer 3 is roughly equivalent to the Internet Layer of the TCP/IP model and the Layer 4 (Transport Layer) of the OSI model is roughly equivalent to the Host-to-Host layer of the TCP/IP model. The above two layers perform network segmentation. Based on the above information, answer the following questions.
(a) Describe in detail how packets are segmented by the Host-to-host layer (Transport Layer) Internet Layer of the TCP/IP model.
(b) Do all packets arrive at their destination in the order in which they were segmented and transmitted? Why or why not?
(c) Describe how segmented packets are re-arranged or reassembled at the packets’ destination to ensure that received segmented packets match the order in which they were segmented and transmitted.
(d) How are errors handled during transmission of segmented packets?
(e) What's the difference between a TCP segment and a TCP packet?
Please answer the following questions and requirements to write your paper of 4–5 pages. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
Please include the following elements in your paper:
A title page
A report that includes the following:
An introduction to the contents of the report
Detailed explanations about the items listed regarding network segmentation, error handling, TCP segments and TCP packets.
Please cite your references in APA format.
Weeks 3 and 4
Individual Project :
Deliverable Length : 3-5 pages
Please answer the following questions and requirements to write your 3–5 page paper. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
The following is a case study about a design company.
You are a senior network administrator for a networking solutions firm. Years ago, you installed a small LAN at a design company. It is growing fast and needs your networking solutions firm to upgrade its network. You assigned Liz to the job. That afternoon, while preparing to work on a lab ass.
Discussion Board
Deliverable Length: 4 – 6 paragraphs
An organization has a number of tools available when determining how best to address performance issues on their network. The organization can use subnetting or they can use segmentation.
Discuss the pros and cons of each.
Provide examples of when each would be appropriate.
Individual Project
Deliverable Length: 4 – 5 pages
The OSI Layer 3 (Network Layer) is one of the layers that perform packet segmentation. The OSI Layer 3 is roughly equivalent to the Internet Layer of the TCP/IP model and the Layer 4 (Transport Layer) of the OSI model is roughly equivalent to the Host-to-Host layer of the TCP/IP model. The above two layers perform network segmentation. Based on the above information, answer the following questions.
(a) Describe in detail how packets are segmented by the Host-to-host layer (Transport Layer) Internet Layer of the TCP/IP model.
(b) Do all packets arrive at their destination in the order in which they were segmented and transmitted? Why or why not?
(c) Describe how segmented packets are re-arranged or reassembled at the packets’ destination to ensure that received segmented packets match the order in which they were segmented and transmitted.
(d) How are errors handled during transmission of segmented packets?
(e) What's the difference between a TCP segment and a TCP packet?
Please answer the following questions and requirements to write your paper of 4–5 pages. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
Please include the following elements in your paper:
A title page
A report that includes the following:
An introduction to the contents of the report
Detailed explanations about the items listed regarding network segmentation, error handling, TCP segments and TCP packets.
Please cite your references in APA format.
Weeks 3 and 4
Individual Project :
Deliverable Length : 3-5 pages
Please answer the following questions and requirements to write your 3–5 page paper. As you answer each question, you must provide support or evidence that will enhance and empirically prove your answers. Academic IT articles or real-life IT findings that are not found in journals or other academic sources must be used in supporting your answers. Please use APA style for all cited sources, including your reference page.
The following is a case study about a design company.
You are a senior network administrator for a networking solutions firm. Years ago, you installed a small LAN at a design company. It is growing fast and needs your networking solutions firm to upgrade its network. You assigned Liz to the job. That afternoon, while preparing to work on a lab ass.
Event-Driven, Client-Server Archetypes for E-Commerceijtsrd
The networking solution to symmetric encryption [1] is defined not only by the understanding of write-ahead logging, but also by the extensive need for neural networks. In this position paper, we verify the visualization of red-black trees. In this paper we concentrate our efforts on arguing that local-area networks can be made wireless, authenticated, and Bayesian [2]. Chirag Patel"Event-Driven, Client-Server Archetypes for E-Commerce" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-1 , December 2016, URL: http://www.ijtsrd.com/papers/ijtsrd56.pdf http://www.ijtsrd.com/engineering/computer-engineering/56/event-driven-client-server-archetypes-for-e-commerce/chirag-patel
You've seen how to hack your health, then hack your brain.
But it's tiring to work on oneself relentlessly.
How do you keep the motivation?
Now hack the hacks!
We're curious minds, hackers and tinkerers.
We love to tweak our tools.
But our most important and wonderful tool is our own brain.
How can we understand what's going on so we can hack it?
This is the full-text slide deck for "Hack Your Brain".
You can find all the trivia in "Hack Your Brain - Trivia" and a french (lighter) version in "Hack Your Brain - FR".
These are companion slides to "Hack Your Brain", which has pictures of brilliant people.
All of them have trivia and fun facts, making them even more rememberable. You should "Wikipedia-them-all" :)
Ce sont les slides que j'ai présentées, elles sont un peu légères.
Pour les anecdotes pour les savants, lisez "Hack Your Brain - Trivia"
Pour le détail complet, lisez la version anglaise "Hack Your Brain"
Version étendue du "Ruby Press Pack".
Ce projet est aussi et surtout le vôtre.
En améliorant la présence et la visibilité de Ruby et Rails, vous aidez la communauté, et elle vous aidera en retour :)
Traduire une application n'est pas facile.
GetText est une solution efficace et robuste, souvent ignorée.
Ces slides datent un peu mais restent pertinents. J'y mentionne quelques casse-têtes récurrents : avant de choisir une solution d'I18N, vérifiez bien que vos alternatives gèrent ces cas.
Translations are hard.
GetText is an often overlooked solution, but it has many advantages.
These slides are a bit old but still relevant. They have some details about translations horror stories: before choosing any I18N solution, match these against your prospective answers.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Pushing the limits of ePRTC: 100ns holdover for 100 daysAdtran
At WSTS 2024, Alon Stern explored the topic of parametric holdover and explained how recent research findings can be implemented in real-world PNT networks to achieve 100 nanoseconds of accuracy for up to 100 days.
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Welcome to the first live UiPath Community Day Dubai! Join us for this unique occasion to meet our local and global UiPath Community and leaders. You will get a full view of the MEA region's automation landscape and the AI Powered automation technology capabilities of UiPath. Also, hosted by our local partners Marc Ellis, you will enjoy a half-day packed with industry insights and automation peers networking.
📕 Curious on our agenda? Wait no more!
10:00 Welcome note - UiPath Community in Dubai
Lovely Sinha, UiPath Community Chapter Leader, UiPath MVPx3, Hyper-automation Consultant, First Abu Dhabi Bank
10:20 A UiPath cross-region MEA overview
Ashraf El Zarka, VP and Managing Director MEA, UiPath
10:35: Customer Success Journey
Deepthi Deepak, Head of Intelligent Automation CoE, First Abu Dhabi Bank
11:15 The UiPath approach to GenAI with our three principles: improve accuracy, supercharge productivity, and automate more
Boris Krumrey, Global VP, Automation Innovation, UiPath
12:15 To discover how Marc Ellis leverages tech-driven solutions in recruitment and managed services.
Brendan Lingam, Director of Sales and Business Development, Marc Ellis
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
zkStudyClub - Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex ProofsAlex Pruden
This paper presents Reef, a system for generating publicly verifiable succinct non-interactive zero-knowledge proofs that a committed document matches or does not match a regular expression. We describe applications such as proving the strength of passwords, the provenance of email despite redactions, the validity of oblivious DNS queries, and the existence of mutations in DNA. Reef supports the Perl Compatible Regular Expression syntax, including wildcards, alternation, ranges, capture groups, Kleene star, negations, and lookarounds. Reef introduces a new type of automata, Skipping Alternating Finite Automata (SAFA), that skips irrelevant parts of a document when producing proofs without undermining soundness, and instantiates SAFA with a lookup argument. Our experimental evaluation confirms that Reef can generate proofs for documents with 32M characters; the proofs are small and cheap to verify (under a second).
Paper: https://eprint.iacr.org/2023/1886
Climate Impact of Software Testing at Nordic Testing DaysKari Kakkonen
My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
Elevating Tactical DDD Patterns Through Object CalisthenicsDorra BARTAGUIZ
After immersing yourself in the blue book and its red counterpart, attending DDD-focused conferences, and applying tactical patterns, you're left with a crucial question: How do I ensure my design is effective? Tactical patterns within Domain-Driven Design (DDD) serve as guiding principles for creating clear and manageable domain models. However, achieving success with these patterns requires additional guidance. Interestingly, we've observed that a set of constraints initially designed for training purposes remarkably aligns with effective pattern implementation, offering a more ‘mechanical’ approach. Let's explore together how Object Calisthenics can elevate the design of your tactical DDD patterns, offering concrete help for those venturing into DDD for the first time!
5. Me at 10
vendredi 4 octobre 2013
Here’s me at 10. Young, foolish and frankly? Underwater.
Culture, films, comics: ancient is good.
Well OK but why didn’t it win?
Unless of course it’s... secret.
You noticed that game BTW? Guess what: people are often slowed down because of idolizing things.
6. Me at 20
vendredi 4 octobre 2013
Here’s me at 18~23.
Why the pain? Well I’m in an association and it seems we never learn.
Why don’t we learn? Maybe it’s just hard.
Note that, if it’s secret it’s not my fault I don’t know. I have excuses.
7. Feeling like a kid
vendredi 4 octobre 2013
But I don’t like excuses, or rather, I’d like to find the secret to beat people.
Then I started looking, and I felt like a kid again.
Afraid of the big guys.
How to stand proud when you only have just a pack of menthol sweets?
8. Arrogance
vendredi 4 octobre 2013
Luckily for me, arrogance came back.
I felt like I knew everything.
Then I know I don’t.
Then I try to bluff people in thinking I do.
9. Crew!
Boat!
vendredi 4 octobre 2013
At some point I found something like a crew.
Luckily for me, the Ruby crew is an awesome crew ;)
12. ?
vendredi 4 octobre 2013
We’re lost.
And the path... wow, it’s difficult to even know where it starts.
13. OH: it’s fun to see the
(Node.)JS community be
rocked hard each time they
rediscover old things.
vendredi 4 octobre 2013
This made me laugh because Ruby & Rails is not the cool kid anymore,
so bashing JS guys was fun.
14. Object/Relational Mapping
is the Vietnam of computer
science
- Ted Newark
vendredi 4 octobre 2013
Or not.
I’m not quoting what other, older, less fancy communities say about Ruby.
15. - imperative programming
- object-oriented prog.
- ActiveRecord-oriented prog.
When did it go wrong?
vendredi 4 octobre 2013
At least we have some healthy sense of self-derision to correct ourselves.
16. I would advise students to
pay more attention to the
fundamental ideas rather
than the latest technology.
The technology will be outof-date before they graduate.
Fundamental ideas never
get out of date.
-- David Parnas
vendredi 4 octobre 2013
Wow.
How about human stuff?
Tech changed every 10 years (now rather every 2 years) but humans evolved in millenia so that’s not going anytime soon.
21. In Search of an Understandable Consensus Algorithm
Diego Ongaro and John Ousterhout
Stanford University
(Draft of April 7, 2013, under submission to SOSP)
Abstract
was our most important criterion in evaluating design alternatives. We applied specific techniques to
improve understandability, including decomposition
(Raft separates leader election, log replication, and
safety so that they can be understood relatively independently) and state space reduction (Raft reduces
the degree of nondeterminism and the ways servers
can be inconsistent with each other, in order to make
it easier to reason about the system).
• Strong leader: Raft differs from other consensus algorithms in that it employs a strong form of leadership where only leaders (or would-be leaders) issue
requests; other servers are completely passive. This
makes Raft easier to understand and also simplifies
the implementation.
• Membership changes: Raft’s mechanism for
changing the set of servers in the cluster uses a simple joint consensus approach where the majorities
of two different configurations overlap during transitions.
We performed a user study with 43 graduate students
at two universities to test our hypothesis that Raft is more
understandable than Paxos. After learning both algorithms, students were able to answer questions about Raft
23% better than questions about Paxos.
We have implemented Raft in about 1500 lines of
C++ code, and the implementation is used as part of
RAMCloud [18]. We have also proven the correctness
of the Raft algorithm.
The remainder of the paper introduces the replicated
state machine problem (Section 2), discusses the strengths
and weaknesses of Paxos (Section 3), describes our general approach to understandability (Section 4), presents
the Raft consensus algorithm (Sections 5-7), evaluates
Raft (Section 8), and discusses related work (Section 9).
Raft is a consensus algorithm for managing a replicated
log. It produces a result equivalent to Paxos, and it is
as efficient as Paxos, but its structure is different from
Paxos; this makes Raft more understandable than Paxos
and also provides a better foundation for building practical systems. In order to enhance understandability, Raft
separates the key elements of consensus, such as leader
election and log replication, and it enforces a stronger degree of coherency to reduce the number of states that must
be considered. Raft also includes a new mechanism for
changing the cluster membership, which uses overlapping
majorities to guarantee safety. Results from a user study
demonstrate that Raft is easier for students to learn than
Paxos.
1 Introduction
Consensus algorithms allow a collection of machines
to work as a coherent group that can survive the failures
of some of its members. Because of this, they play a
key role in building reliable large-scale software systems.
Paxos [9, 10] has dominated the discussion of consensus
algorithms over the last decade: most implementations
of consensus are based on Paxos or influenced by it, and
Paxos has become the primary vehicle used to teach students about consensus.
Unfortunately, Paxos is quite difficult to understand, in
spite of numerous attempts to make it more approachable. Furthermore, its architecture is unsuitable for building practical systems, requiring complex changes to create an efficient and complete solution. As a result, both
system builders and students struggle with Paxos.
After struggling with Paxos ourselves, we set out to
find a new consensus algorithm that could provide a better foundation for system building and education. Our approach was unusual in that our primary goal was understandability: could we define a consensus algorithm and
describe it in a way that is significantly easier to learn than
Paxos, and that facilitates the development of intuitions
that are essential for system builders? It was important
not just for the algorithm to work, but for it to be obvious why it works. In addition, the algorithm needed to be
complete enough to cover all the major issues required for
an implementation.
The result of our effort is a consensus algorithm called
Raft. Raft is similar in many ways to existing consensus
algorithms (most notably, Oki and Liskov’s Viewstamped
Replication [17]), but it has several novel aspects:
• Design for understandability: understandability
2 Achieving fault-tolerance with replicated
state machines
Consensus algorithms typically arise in the context of
replicated state machines [20]. In this approach, state machines on a collection of servers compute identical copies
of the same state and can continue operating even if some
of the servers are down. Replicated state machines are
used to solve a variety of fault-tolerance problems in distributed systems. For example, large-scale systems that
have a single cluster leader, such as GFS [4], HDFS [21],
and RAMCloud [18], typically use a separate replicated
state machine to manage leader election and store config1
vendredi 4 octobre 2013
So now you’ve found some papers.
22. In Search of an Understandable Consensus Algorithm
Diego Ongaro and John Ousterhout
Stanford University
(Draft of April 7, 2013, under submission to SOSP)
Abstract
was our most important criterion in evaluating design alternatives. We applied specific techniques to
improve understandability, including decomposition
(Raft separates leader election, log replication, and
safety so that they can be understood relatively independently) and state space reduction (Raft reduces
the degree of nondeterminism and the ways servers
can be inconsistent with each other, in order to make
it easier to reason about the system).
• Strong leader: Raft differs from other consensus algorithms in that it employs a strong form of leadership where only leaders (or would-be leaders) issue
requests; other servers are completely passive. This
makes Raft easier to understand and also simplifies
the implementation.
• Membership changes: Raft’s mechanism for
changing the set of servers in the cluster uses a simple joint consensus approach where the majorities
of two different configurations overlap during transitions.
We performed a user study with 43 graduate students
at two universities to test our hypothesis that Raft is more
understandable than Paxos. After learning both algorithms, students were able to answer questions about Raft
23% better than questions about Paxos.
We have implemented Raft in about 1500 lines of
C++ code, and the implementation is used as part of
RAMCloud [18]. We have also proven the correctness
of the Raft algorithm.
The remainder of the paper introduces the replicated
state machine problem (Section 2), discusses the strengths
and weaknesses of Paxos (Section 3), describes our general approach to understandability (Section 4), presents
the Raft consensus algorithm (Sections 5-7), evaluates
Raft (Section 8), and discusses related work (Section 9).
Raft is a consensus algorithm for managing a replicated
log. It produces a result equivalent to Paxos, and it is
as efficient as Paxos, but its structure is different from
Paxos; this makes Raft more understandable than Paxos
and also provides a better foundation for building practical systems. In order to enhance understandability, Raft
separates the key elements of consensus, such as leader
election and log replication, and it enforces a stronger degree of coherency to reduce the number of states that must
be considered. Raft also includes a new mechanism for
changing the cluster membership, which uses overlapping
majorities to guarantee safety. Results from a user study
demonstrate that Raft is easier for students to learn than
Paxos.
1 Introduction
Scriptless
Attacks
Consensus algorithms allow a collection of machines
to work as a coherent group that can survive the failures
of some of its members. Because of this, they play a
key role in building reliable large-scale software systems.
Paxos [9, 10] has dominated the discussion of consensus
algorithms over the last decade: most implementations
of consensus are based on Paxos or influenced by it, and
Paxos has become the primary vehicle used to teach students about consensus.
Unfortunately, Paxos is quite difficult to understand, in
spite of numerous attempts to make it more approachable. Furthermore, its architecture is unsuitable for building practical systems, requiring complex changes to create an efficient and complete solution. As a result, both
system builders and students struggle with Paxos.
After struggling with Paxos ourselves, we set out to
find a new consensus algorithm that could provide a better foundation for system building and education. Our approach was unusual in that our primary goal was understandability: could we define a consensus algorithm and
describe it in a way that is significantly easier to learn than
Paxos, and that facilitates the development of intuitions
that are essential for system builders? It was important
not just for the algorithm to work, but for it to be obvious why it works. In addition, the algorithm needed to be
complete enough to cover all the major issues required for
an implementation.
The result of our effort is a consensus algorithm called
Raft. Raft is similar in many ways to existing consensus
algorithms (most notably, Oki and Liskov’s Viewstamped
Replication [17]), but it has several novel aspects:
• Design for understandability: understandability
Lamport’s
Paxos
2 Achieving fault-tolerance with replicated
state machines
Consensus algorithms typically arise in the context of
replicated state machines [20]. In this approach, state machines on a collection of servers compute identical copies
of the same state and can continue operating even if some
of the servers are down. Replicated state machines are
used to solve a variety of fault-tolerance problems in distributed systems. For example, large-scale systems that
have a single cluster leader, such as GFS [4], HDFS [21],
and RAMCloud [18], typically use a separate replicated
state machine to manage leader election and store config-
1
vendredi 4 octobre 2013
These are pretty different papers by the way.
24. In Search of an Understandable Consensus Algorithm
Diego Ongaro and John Ousterhout
Stanford University
(Draft of April 7, 2013, under submission to SOSP)
Abstract
Raft is a consensus algorithm for managing a replicated
log. It produces a result equivalent to Paxos, and it is
as efficient as Paxos, but its structure is different from
Paxos; this makes Raft more understandable than Paxos
and also provides a better foundation for building practical systems. In order to enhance understandability, Raft
separates the key elements of consensus, such as leader
election and log replication, and it enforces a stronger degree of coherency to reduce the number of states that must
be considered. Raft also includes a new mechanism for
changing the cluster membership, which uses overlapping
majorities to guarantee safety. Results from a user study
demonstrate that Raft is easier for students to learn than
Paxos.
1 Introduction
Consensus algorithms allow a collection of machines
to work as a coherent group that can survive the failures
of some of its members. Because of this, they play a
key role in building reliable large-scale software systems.
Paxos [9, 10] has dominated the discussion of consensus
algorithms over the last decade: most implementations
of consensus are based on Paxos or influenced by it, and
Paxos has become the primary vehicle used to teach students about consensus.
vendredi 4 Unfortunately, Paxos is quite difficult to understand, in
octobre 2013
spite of numerous attempts to make it more approachable. Furthermore, its architecture is unsuitable for building practical systems, requiring complex changes to create an efficient and complete solution. As a result, both
was our most important criterion in evaluating design alternatives. We applied specific techniques to
improve understandability, including decomposition
(Raft separates leader election, log replication, and
safety so that they can be understood relatively independently) and state space reduction (Raft reduces
the degree of nondeterminism and the ways servers
can be inconsistent with each other, in order to make
it easier to reason about the system).
• Strong leader: Raft differs from other consensus algorithms in that it employs a strong form of leadership where only leaders (or would-be leaders) issue
requests; other servers are completely passive. This
makes Raft easier to understand and also simplifies
the implementation.
• Membership changes: Raft’s mechanism for
changing the set of servers in the cluster uses a simple joint consensus approach where the majorities
of two different configurations overlap during transitions.
We performed a user study with 43 graduate students
at two universities to test our hypothesis that Raft is more
understandable than Paxos. After learning both algorithms, students were able to answer questions about Raft
23% better than questions about Paxos.
We have implemented Raft in about 1500 lines of
C++ code, and the implementation is used as part of
RAMCloud [18]. We have also proven the correctness
of the Raft algorithm.
The remainder of the paper introduces the replicated
Lamport’s Paxos
34. Find nuggets
vendredi 4 octobre 2013
"When you want to do something differently from the rest of the world,
it's a good idea to look into whether the rest of the world knows
something you don't."