Adding DDoS preventing techniques

2022-09-05 10:35:47 -04:00 · 2022-09-05 10:35:47 -04:00 · ebd9a6a771
parent 7e8f93e57d
commit ebd9a6a771
1 changed files with 173 additions and 82 deletions
--- a/README.md
+++ b/README.md
@ -97,87 +97,178 @@ Review the [Contributing Guidelines](CONTRIBUTING.md).
  <br/>
 </p>

-* [System design topics: start here](#system-design-topics-start-here)
-    * [Step 1: Review the scalability video lecture](#step-1-review-the-scalability-video-lecture)
-    * [Step 2: Review the scalability article](#step-2-review-the-scalability-article)
-    * [Next steps](#next-steps)
-* [Performance vs scalability](#performance-vs-scalability)
-* [Latency vs throughput](#latency-vs-throughput)
-* [Availability vs consistency](#availability-vs-consistency)
-    * [CAP theorem](#cap-theorem)
-        * [CP - consistency and partition tolerance](#cp---consistency-and-partition-tolerance)
-        * [AP - availability and partition tolerance](#ap---availability-and-partition-tolerance)
-* [Consistency patterns](#consistency-patterns)
-    * [Weak consistency](#weak-consistency)
-    * [Eventual consistency](#eventual-consistency)
-    * [Strong consistency](#strong-consistency)
-* [Availability patterns](#availability-patterns)
-    * [Fail-over](#fail-over)
-    * [Replication](#replication)
-    * [Availability in numbers](#availability-in-numbers)
-* [Domain name system](#domain-name-system)
-* [Content delivery network](#content-delivery-network)
-    * [Push CDNs](#push-cdns)
-    * [Pull CDNs](#pull-cdns)
-* [Load balancer](#load-balancer)
-    * [Active-passive](#active-passive)
-    * [Active-active](#active-active)
-    * [Layer 4 load balancing](#layer-4-load-balancing)
-    * [Layer 7 load balancing](#layer-7-load-balancing)
-    * [Horizontal scaling](#horizontal-scaling)
-* [Reverse proxy (web server)](#reverse-proxy-web-server)
-    * [Load balancer vs reverse proxy](#load-balancer-vs-reverse-proxy)
-* [Application layer](#application-layer)
-    * [Microservices](#microservices)
-    * [Service discovery](#service-discovery)
-* [Database](#database)
-    * [Relational database management system (RDBMS)](#relational-database-management-system-rdbms)
-        * [Master-slave replication](#master-slave-replication)
-        * [Master-master replication](#master-master-replication)
-        * [Federation](#federation)
-        * [Sharding](#sharding)
-        * [Denormalization](#denormalization)
-        * [SQL tuning](#sql-tuning)
-    * [NoSQL](#nosql)
-        * [Key-value store](#key-value-store)
-        * [Document store](#document-store)
-        * [Wide column store](#wide-column-store)
-        * [Graph Database](#graph-database)
-    * [SQL or NoSQL](#sql-or-nosql)
-* [Cache](#cache)
-    * [Client caching](#client-caching)
-    * [CDN caching](#cdn-caching)
-    * [Web server caching](#web-server-caching)
-    * [Database caching](#database-caching)
-    * [Application caching](#application-caching)
-    * [Caching at the database query level](#caching-at-the-database-query-level)
-    * [Caching at the object level](#caching-at-the-object-level)
-    * [When to update the cache](#when-to-update-the-cache)
-        * [Cache-aside](#cache-aside)
-        * [Write-through](#write-through)
-        * [Write-behind (write-back)](#write-behind-write-back)
-        * [Refresh-ahead](#refresh-ahead)
-* [Asynchronism](#asynchronism)
-    * [Message queues](#message-queues)
-    * [Task queues](#task-queues)
-    * [Back pressure](#back-pressure)
-* [Communication](#communication)
-    * [Transmission control protocol (TCP)](#transmission-control-protocol-tcp)
-    * [User datagram protocol (UDP)](#user-datagram-protocol-udp)
-    * [Remote procedure call (RPC)](#remote-procedure-call-rpc)
-    * [Representational state transfer (REST)](#representational-state-transfer-rest)
-* [Security](#security)
-* [Appendix](#appendix)
-    * [Powers of two table](#powers-of-two-table)
-    * [Latency numbers every programmer should know](#latency-numbers-every-programmer-should-know)
-    * [Additional system design interview questions](#additional-system-design-interview-questions)
-    * [Real world architectures](#real-world-architectures)
-    * [Company architectures](#company-architectures)
-    * [Company engineering blogs](#company-engineering-blogs)
-* [Under development](#under-development)
-* [Credits](#credits)
-* [Contact info](#contact-info)
-* [License](#license)
+- [The System Design Primer](#the-system-design-primer)
+  - [Motivation](#motivation)
+    - [Learn how to design large-scale systems](#learn-how-to-design-large-scale-systems)
+    - [Learn from the open source community](#learn-from-the-open-source-community)
+    - [Prep for the system design interview](#prep-for-the-system-design-interview)
+  - [Anki flashcards](#anki-flashcards)
+    - [Coding Resource: Interactive Coding Challenges](#coding-resource-interactive-coding-challenges)
+  - [Contributing](#contributing)
+  - [Index of system design topics](#index-of-system-design-topics)
+  - [Study guide](#study-guide)
+  - [How to approach a system design interview question](#how-to-approach-a-system-design-interview-question)
+    - [Step 1: Outline use cases, constraints, and assumptions](#step-1-outline-use-cases-constraints-and-assumptions)
+    - [Step 2: Create a high level design](#step-2-create-a-high-level-design)
+    - [Step 3: Design core components](#step-3-design-core-components)
+    - [Step 4: Scale the design](#step-4-scale-the-design)
+    - [Back-of-the-envelope calculations](#back-of-the-envelope-calculations)
+    - [Source(s) and further reading](#sources-and-further-reading)
+  - [System design interview questions with solutions](#system-design-interview-questions-with-solutions)
+    - [Design Pastebin.com (or Bit.ly)](#design-pastebincom-or-bitly)
+    - [Design the Twitter timeline and search (or Facebook feed and search)](#design-the-twitter-timeline-and-search-or-facebook-feed-and-search)
+    - [Design a web crawler](#design-a-web-crawler)
+    - [Design Mint.com](#design-mintcom)
+    - [Design the data structures for a social network](#design-the-data-structures-for-a-social-network)
+    - [Design a key-value store for a search engine](#design-a-key-value-store-for-a-search-engine)
+    - [Design Amazon's sales ranking by category feature](#design-amazons-sales-ranking-by-category-feature)
+    - [Design a system that scales to millions of users on AWS](#design-a-system-that-scales-to-millions-of-users-on-aws)
+  - [Object-oriented design interview questions with solutions](#object-oriented-design-interview-questions-with-solutions)
+  - [System design topics: start here](#system-design-topics-start-here)
+    - [Step 1: Review the scalability video lecture](#step-1-review-the-scalability-video-lecture)
+    - [Step 2: Review the scalability article](#step-2-review-the-scalability-article)
+    - [Next steps](#next-steps)
+  - [Performance vs scalability](#performance-vs-scalability)
+    - [Source(s) and further reading](#sources-and-further-reading-1)
+  - [Latency vs throughput](#latency-vs-throughput)
+    - [Source(s) and further reading](#sources-and-further-reading-2)
+  - [Availability vs consistency](#availability-vs-consistency)
+    - [CAP theorem](#cap-theorem)
+      - [CP - consistency and partition tolerance](#cp---consistency-and-partition-tolerance)
+      - [AP - availability and partition tolerance](#ap---availability-and-partition-tolerance)
+    - [Source(s) and further reading](#sources-and-further-reading-3)
+  - [Consistency patterns](#consistency-patterns)
+    - [Weak consistency](#weak-consistency)
+    - [Eventual consistency](#eventual-consistency)
+    - [Strong consistency](#strong-consistency)
+    - [Source(s) and further reading](#sources-and-further-reading-4)
+  - [Availability patterns](#availability-patterns)
+    - [Fail-over](#fail-over)
+      - [Active-passive](#active-passive)
+      - [Active-active](#active-active)
+    - [Disadvantage(s): failover](#disadvantages-failover)
+    - [Replication](#replication)
+      - [Master-slave and master-master](#master-slave-and-master-master)
+    - [Availability in numbers](#availability-in-numbers)
+      - [99.9% availability - three 9s](#999-availability---three-9s)
+      - [99.99% availability - four 9s](#9999-availability---four-9s)
+      - [Availability in parallel vs in sequence](#availability-in-parallel-vs-in-sequence)
+          - [In sequence](#in-sequence)
+          - [In parallel](#in-parallel)
+  - [Domain name system](#domain-name-system)
+    - [Disadvantage(s): DNS](#disadvantages-dns)
+    - [Source(s) and further reading](#sources-and-further-reading-5)
+  - [Content delivery network](#content-delivery-network)
+    - [Push CDNs](#push-cdns)
+    - [Pull CDNs](#pull-cdns)
+    - [Disadvantage(s): CDN](#disadvantages-cdn)
+    - [Source(s) and further reading](#sources-and-further-reading-6)
+  - [Load balancer](#load-balancer)
+    - [Layer 4 load balancing](#layer-4-load-balancing)
+    - [Layer 7 load balancing](#layer-7-load-balancing)
+    - [Horizontal scaling](#horizontal-scaling)
+      - [Disadvantage(s): horizontal scaling](#disadvantages-horizontal-scaling)
+    - [Disadvantage(s): load balancer](#disadvantages-load-balancer)
+    - [Source(s) and further reading](#sources-and-further-reading-7)
+  - [Reverse proxy (web server)](#reverse-proxy-web-server)
+    - [Load balancer vs reverse proxy](#load-balancer-vs-reverse-proxy)
+    - [Disadvantage(s): reverse proxy](#disadvantages-reverse-proxy)
+    - [Source(s) and further reading](#sources-and-further-reading-8)
+  - [Application layer](#application-layer)
+    - [Microservices](#microservices)
+    - [Service Discovery](#service-discovery)
+    - [Disadvantage(s): application layer](#disadvantages-application-layer)
+    - [Source(s) and further reading](#sources-and-further-reading-9)
+  - [Database](#database)
+    - [Relational database management system (RDBMS)](#relational-database-management-system-rdbms)
+      - [Master-slave replication](#master-slave-replication)
+        - [Disadvantage(s): master-slave replication](#disadvantages-master-slave-replication)
+      - [Master-master replication](#master-master-replication)
+        - [Disadvantage(s): master-master replication](#disadvantages-master-master-replication)
+        - [Disadvantage(s): replication](#disadvantages-replication)
+        - [Source(s) and further reading: replication](#sources-and-further-reading-replication)
+      - [Federation](#federation)
+        - [Disadvantage(s): federation](#disadvantages-federation)
+        - [Source(s) and further reading: federation](#sources-and-further-reading-federation)
+      - [Sharding](#sharding)
+        - [Disadvantage(s): sharding](#disadvantages-sharding)
+        - [Source(s) and further reading: sharding](#sources-and-further-reading-sharding)
+      - [Denormalization](#denormalization)
+        - [Disadvantage(s): denormalization](#disadvantages-denormalization)
+          - [Source(s) and further reading: denormalization](#sources-and-further-reading-denormalization)
+      - [SQL tuning](#sql-tuning)
+        - [Tighten up the schema](#tighten-up-the-schema)
+        - [Use good indices](#use-good-indices)
+        - [Avoid expensive joins](#avoid-expensive-joins)
+        - [Partition tables](#partition-tables)
+        - [Tune the query cache](#tune-the-query-cache)
+        - [Source(s) and further reading: SQL tuning](#sources-and-further-reading-sql-tuning)
+    - [NoSQL](#nosql)
+      - [Key-value store](#key-value-store)
+        - [Source(s) and further reading: key-value store](#sources-and-further-reading-key-value-store)
+      - [Document store](#document-store)
+        - [Source(s) and further reading: document store](#sources-and-further-reading-document-store)
+      - [Wide column store](#wide-column-store)
+        - [Source(s) and further reading: wide column store](#sources-and-further-reading-wide-column-store)
+      - [Graph database](#graph-database)
+        - [Source(s) and further reading: graph](#sources-and-further-reading-graph)
+      - [Source(s) and further reading: NoSQL](#sources-and-further-reading-nosql)
+    - [SQL or NoSQL](#sql-or-nosql)
+        - [Source(s) and further reading: SQL or NoSQL](#sources-and-further-reading-sql-or-nosql)
+  - [Cache](#cache)
+    - [Client caching](#client-caching)
+    - [CDN caching](#cdn-caching)
+    - [Web server caching](#web-server-caching)
+    - [Database caching](#database-caching)
+    - [Application caching](#application-caching)
+    - [Caching at the database query level](#caching-at-the-database-query-level)
+    - [Caching at the object level](#caching-at-the-object-level)
+    - [When to update the cache](#when-to-update-the-cache)
+      - [Cache-aside](#cache-aside)
+        - [Disadvantage(s): cache-aside](#disadvantages-cache-aside)
+      - [Write-through](#write-through)
+        - [Disadvantage(s): write through](#disadvantages-write-through)
+      - [Write-behind (write-back)](#write-behind-write-back)
+        - [Disadvantage(s): write-behind](#disadvantages-write-behind)
+      - [Refresh-ahead](#refresh-ahead)
+        - [Disadvantage(s): refresh-ahead](#disadvantages-refresh-ahead)
+    - [Disadvantage(s): cache](#disadvantages-cache)
+    - [Source(s) and further reading](#sources-and-further-reading-10)
+  - [Asynchronism](#asynchronism)
+    - [Message queues](#message-queues)
+    - [Task queues](#task-queues)
+    - [Back pressure](#back-pressure)
+    - [Disadvantage(s): asynchronism](#disadvantages-asynchronism)
+    - [Source(s) and further reading](#sources-and-further-reading-11)
+  - [Communication](#communication)
+    - [Hypertext transfer protocol (HTTP)](#hypertext-transfer-protocol-http)
+      - [Source(s) and further reading: HTTP](#sources-and-further-reading-http)
+    - [Transmission control protocol (TCP)](#transmission-control-protocol-tcp)
+    - [User datagram protocol (UDP)](#user-datagram-protocol-udp)
+      - [Source(s) and further reading: TCP and UDP](#sources-and-further-reading-tcp-and-udp)
+    - [Remote procedure call (RPC)](#remote-procedure-call-rpc)
+      - [Disadvantage(s): RPC](#disadvantages-rpc)
+    - [Representational state transfer (REST)](#representational-state-transfer-rest)
+      - [Disadvantage(s): REST](#disadvantages-rest)
+    - [RPC and REST calls comparison](#rpc-and-rest-calls-comparison)
+      - [Source(s) and further reading: REST and RPC](#sources-and-further-reading-rest-and-rpc)
+  - [Security](#security)
+    - [Source(s) and further reading](#sources-and-further-reading-12)
+  - [Appendix](#appendix)
+    - [Powers of two table](#powers-of-two-table)
+      - [Source(s) and further reading](#sources-and-further-reading-13)
+    - [Latency numbers every programmer should know](#latency-numbers-every-programmer-should-know)
+      - [Latency numbers visualized](#latency-numbers-visualized)
+      - [Source(s) and further reading](#sources-and-further-reading-14)
+    - [Additional system design interview questions](#additional-system-design-interview-questions)
+    - [Real world architectures](#real-world-architectures)
+    - [Company architectures](#company-architectures)
+    - [Company engineering blogs](#company-engineering-blogs)
+      - [Source(s) and further reading](#sources-and-further-reading-15)
+  - [Under development](#under-development)
+  - [Credits](#credits)
+  - [Contact info](#contact-info)
+  - [License](#license)

 ## Study guide

@ -608,7 +699,7 @@ Services such as [CloudFlare](https://www.cloudflare.com/dns/) and [Route 53](ht

 * Accessing a DNS server introduces a slight delay, although mitigated by caching described above.
 * DNS server management could be complex and is generally managed by [governments, ISPs, and large companies](http://superuser.com/questions/472695/who-controls-the-dns-servers/472729).
-* DNS services have recently come under [DDoS attack](http://dyn.com/blog/dyn-analysis-summary-of-friday-october-21-attack/), preventing users from accessing websites such as Twitter without knowing Twitter's IP address(es).
+* DNS services have recently come under [DDoS attack](http://dyn.com/blog/dyn-analysis-summary-of-friday-october-21-attack/), preventing users from accessing websites such as Twitter without knowing Twitter's IP address(es). Common techniques to prevent DDoS are implementing Rate limiting and Firewall.

 ### Source(s) and further reading