diff --git a/README-ru.md b/README-ru.md
index 8b54f5bb..8d828004 100644
--- a/README-ru.md
+++ b/README-ru.md
@@ -1,9 +1,16 @@
 [English](README.md) | [日本語](README-ja.md) | **[Русский](README-ru.md)** | [简体中文](README-zh-Hans.md) | [繁體中文](README-zh-TW.md) <!-- l10n:select -->
+
+<!-- l10n:p
+**Help [translate](TRANSLATIONS.md) this guide!**
+l10n:p -->
+
+**Помогайте [переводить](TRANSLATIONS.md) это руководство!**
+
 <!-- l10n:p
 # The System Design Primer
 
 <p align="center">
-  <img src="http://i.imgur.com/jj3A5N8.png"/>
+  <img src="images/jj3A5N8.png">
   <br/>
 </p>
 l10n:p -->
@@ -15,7 +22,7 @@ l10n:p -->
 <!-- l10n:ignore end -->
 
 <p align="center">
-  <img src="http://i.imgur.com/jj3A5N8.png"/>
+  <img src="images/jj3A5N8.png">
   <br/>
 </p>
 
@@ -99,7 +106,7 @@ l10n:p -->
 ## Anki flashcards
 
 <p align="center">
-  <img src="http://i.imgur.com/zdCAkB3.png"/>
+  <img src="images/zdCAkB3.png">
   <br/>
 </p>
 
@@ -115,7 +122,7 @@ l10n:p -->
 ## Карточки Anki
 
 <p align="center">
-  <img src="http://i.imgur.com/zdCAkB3.png"/>
+  <img src="images/zdCAkB3.png">
   <br/>
 </p>motivation
 
@@ -133,7 +140,7 @@ l10n:p -->
 Looking for resources to help you prep for the [**Coding Interview**](https://github.com/donnemartin/interactive-coding-challenges)?
 
 <p align="center">
-  <img src="http://i.imgur.com/b4YtAEN.png"/>
+  <img src="images/b4YtAEN.png">
   <br/>
 </p>
 
@@ -147,7 +154,7 @@ l10n:p -->
 Ищете ресурсы для подготовки к [**Coding Interview**](https://github.com/donnemartin/interactive-coding-challenges)?
 
 <p align="center">
-  <img src="http://i.imgur.com/b4YtAEN.png"/>
+  <img src="images/b4YtAEN.png">
   <br/>
 </p>
 
@@ -195,7 +202,7 @@ l10n:p -->
 > Each section contains links to more in-depth resources.
 
 <p align="center">
-  <img src="http://i.imgur.com/jrUBAF7.png"/>
+  <img src="images/jrUBAF7.png">
   <br/>
 </p>
 
@@ -290,7 +297,7 @@ l10n:p -->
 > Каждый раздел содержит ссылки на более подробное описание.
 
 <p align="center">
-  <img src="http://i.imgur.com/jrUBAF7.png"/>
+  <img src="images/jrUBAF7.png">
   <br/>
 </p>
 
@@ -395,7 +402,7 @@ l10n:p -->
 
 > Suggested topics to review based on your interview timeline (short, medium, long).
 
-![Imgur](http://i.imgur.com/OfVllex.png)
+![Imgur](images/OfVllex.png)
 
 **Q: For interviews, do I need to know everything here?**
 
@@ -432,7 +439,7 @@ l10n:p -->
 
 > Предлагаемые темы для повторения в зависимости от того, сколько у вас есть времени для подготовки к интервью (мало, средне, много)
 
-![Imgur](http://i.imgur.com/OfVllex.png)
+![Imgur](images/OfVllex.png)
 
 **Вопрос: Надо ли мне знать все из этого документа для интервью?**
 
@@ -655,112 +662,112 @@ l10n:p -->
 
 [View exercise and solution](solutions/system_design/pastebin/README.md)
 
-![Imgur](http://i.imgur.com/4edXG0T.png)
+![Imgur](images/4edXG0T.png)
 l10n:p -->
 
 ### Спроектируйте Pastebin.com (or Bit.ly)
 
 [Требования и решение](solutions/system_design/pastebin/README.md)
 
-![Imgur](http://i.imgur.com/4edXG0T.png)
+![Imgur](images/4edXG0T.png)
 
 <!-- l10n:p
 ### Design the Twitter timeline and search (or Facebook feed and search)
 
 [View exercise and solution](solutions/system_design/twitter/README.md)
 
-![Imgur](http://i.imgur.com/jrUBAF7.png)
+![Imgur](images/jrUBAF7.png)
 l10n:p -->
 
 ### Спроектируйте ленту Twitter или Facebook и поиск
 
 [Требования и решение](solutions/system_design/twitter/README.md)
 
-![Imgur](http://i.imgur.com/jrUBAF7.png)
+![Imgur](images/jrUBAF7.png)
 
 <!-- l10n:p
 ### Design a web crawler
 
 [View exercise and solution](solutions/system_design/web_crawler/README.md)
 
-![Imgur](http://i.imgur.com/bWxPtQA.png)
+![Imgur](images/bWxPtQA.png)
 l10n:p -->
 
 ### Спроектируйте веб-сканер
 
 [Требования и решение](solutions/system_design/web_crawler/README.md)
 
-![Imgur](http://i.imgur.com/bWxPtQA.png)
+![Imgur](images/bWxPtQA.png)
 
 <!-- l10n:p
 ### Design Mint.com
 
 [View exercise and solution](solutions/system_design/mint/README.md)
 
-![Imgur](http://i.imgur.com/V5q57vU.png)
+![Imgur](images/V5q57vU.png)
 l10n:p -->
 
 ### Спроектируйте Mint.com
 
 [Требования и решение](solutions/system_design/mint/README.md)
 
-![Imgur](http://i.imgur.com/V5q57vU.png)
+![Imgur](images/V5q57vU.png)
 
 <!-- l10n:p
 ### Design the data structures for a social network
 
 [View exercise and solution](solutions/system_design/social_graph/README.md)
 
-![Imgur](http://i.imgur.com/cdCv5g7.png)
+![Imgur](images/cdCv5g7.png)
 l10n:p -->
 
 ### Спроектируйте структуру данных для социальной сети
 
 [Требования и решение](solutions/system_design/social_graph/README.md)
 
-![Imgur](http://i.imgur.com/cdCv5g7.png)
+![Imgur](images/cdCv5g7.png)
 
 <!-- l10n:p
 ### Design a key-value store for a search engine
 
 [View exercise and solution](solutions/system_design/query_cache/README.md)
 
-![Imgur](http://i.imgur.com/4j99mhe.png)
+![Imgur](images/4j99mhe.png)
 l10n:p -->
 
 ### Спроектируйте хранилище типа "ключ-значение" для поисковика
 
 [Требования и решение](solutions/system_design/query_cache/README.md)
 
-![Imgur](http://i.imgur.com/4j99mhe.png)
+![Imgur](images/4j99mhe.png)
 
 <!-- l10n:p
 ### Design Amazon's sales ranking by category feature
 
 [View exercise and solution](solutions/system_design/sales_rank/README.md)
 
-![Imgur](http://i.imgur.com/MzExP06.png)
+![Imgur](images/MzExP06.png)
 l10n:p -->
 
 ### Спроектируйте ранжированирование товаров Amazon по категориям
 
 [Требование и решение](solutions/system_design/sales_rank/README.md)
 
-![Imgur](http://i.imgur.com/MzExP06.png)
+![Imgur](images/MzExP06.png)
 
 <!-- l10n:p
 ### Design a system that scales to millions of users on AWS
 
 [View exercise and solution](solutions/system_design/scaling_aws/README.md)
 
-![Imgur](http://i.imgur.com/jj3A5N8.png)
+![Imgur](images/jj3A5N8.png)
 l10n:p -->
 
 ### Спроектируйте систему, которая масштабируются на миллионы пользователей с помощью AWS
 
 [Требования и решение](solutions/system_design/scaling_aws/README.md)
 
-![Imgur](http://i.imgur.com/jj3A5N8.png)
+![Imgur](images/jj3A5N8.png)
 
 <!-- l10n:p
 ## Object-oriented design interview questions with solutions
@@ -960,7 +967,7 @@ l10n:p -->
 ### CAP theorem
 
 <p align="center">
-  <img src="http://i.imgur.com/bgLMI2u.png"/>
+  <img src="images/bgLMI2u.png">
   <br/>
   <i><a href=http://robertgreiner.com/2014/08/cap-theorem-revisited>Source: CAP theorem revisited</a></i>
 </p>
@@ -977,7 +984,7 @@ l10n:p -->
 ### Теорема CAP
 
 <p align="center">
-  <img src="http://i.imgur.com/bgLMI2u.png"/>
+  <img src="images/bgLMI2u.png">
   <br/>
   <i><a href=http://robertgreiner.com/2014/08/cap-theorem-revisited>Источник: CAP theorem revisited</a></i>
   <br/>
@@ -1285,7 +1292,7 @@ l10n:p -->
 ## Domain name system
 
 <p align="center">
-  <img src="http://i.imgur.com/IOyLj4i.jpg"/>
+  <img src="images/IOyLj4i.jpg">
   <br/>
   <i><a href=http://www.slideshare.net/srikrupa5/dns-security-presentation-issa>Source: DNS security presentation</a></i>
 </p>
@@ -1312,7 +1319,7 @@ l10n:p -->
 ## Систем доменных имен
 
 <p align="center">
-  <img src="http://i.imgur.com/IOyLj4i.jpg"/>
+  <img src="images/IOyLj4i.jpg">
   <br/>
   <i><a href=http://www.slideshare.net/srikrupa5/dns-security-presentation-issa>Источник: DNS security presentation</a></i>
 </p>
@@ -1369,7 +1376,7 @@ l10n:p -->
 ## Content delivery network
 
 <p align="center">
-  <img src="http://i.imgur.com/h9TAuGI.jpg"/>
+  <img src="images/h9TAuGI.jpg">
   <br/>
   <i><a href=https://www.creative-artworks.eu/why-use-a-content-delivery-network-cdn/>Source: Why use a CDN</a></i>
 </p>
@@ -1385,7 +1392,7 @@ l10n:p -->
 ## Сеть доставки содержимого (CDN)
 
 <p align="center">
-  <img src="http://i.imgur.com/h9TAuGI.jpg"/>
+  <img src="images/h9TAuGI.jpg">
   <br/>
   <i><a href=https://www.creative-artworks.eu/why-use-a-content-delivery-network-cdn/>Источник: Why use a CDN</a></i>
 </p>
@@ -1454,7 +1461,7 @@ l10n:p -->
 ## Load balancer
 
 <p align="center">
-  <img src="http://i.imgur.com/h81n9iK.png"/>
+  <img src="images/h81n9iK.png">
   <br/>
   <i><a href=http://horicky.blogspot.com/2010/10/scalable-system-design-patterns.html>Source: Scalable system design patterns</a></i>
 </p>
@@ -1488,7 +1495,7 @@ l10n:p -->
 ## Балансировщик нагрузки
 
 <p align="center">
-  <img src="http://i.imgur.com/h81n9iK.png"/>
+  <img src="images/h81n9iK.png">
   <br/>
   <i><a href=http://horicky.blogspot.com/2010/10/scalable-system-design-patterns.html>Source: Scalable system design patterns</a></i>
 </p>
@@ -1608,7 +1615,7 @@ l10n:p -->
 ## Reverse proxy (web server)
 
 <p align="center">
-  <img src="http://i.imgur.com/n41Azff.png"/>
+  <img src="images/n41Azff.png">
   <br/>
   <i><a href=https://upload.wikimedia.org/wikipedia/commons/6/67/Reverse_proxy_h2g2bob.svg>Source: Wikipedia</a></i>
   <br/>
@@ -1634,7 +1641,7 @@ l10n:p -->
 ## Обратный прокси-сервер (Reverse proxy)
 
 <p align="center">
-  <img src="http://i.imgur.com/n41Azff.png"/>
+  <img src="images/n41Azff.png">
   <br/>
   <i><a href=https://upload.wikimedia.org/wikipedia/commons/6/67/Reverse_proxy_h2g2bob.svg>Source: Wikipedia</a></i>
   <br/>
@@ -1702,7 +1709,7 @@ l10n:p -->
 ## Application layer
 
 <p align="center">
-  <img src="http://i.imgur.com/yB5SYwm.png"/>
+  <img src="images/yB5SYwm.png">
   <br/>
   <i><a href=http://lethain.com/introduction-to-architecting-systems-for-scale/#platform_layer>Source: Intro to architecting systems for scale</a></i>
 </p>
@@ -1715,7 +1722,7 @@ l10n:p -->
 ## Уровень приложений
 
 <p align="center">
-  <img src="http://i.imgur.com/yB5SYwm.png"/>
+  <img src="images/yB5SYwm.png">
   <br/>
   <i><a href=http://lethain.com/introduction-to-architecting-systems-for-scale/#platform_layer>Source: Intro to architecting systems for scale</a></i>
 </p>
@@ -1782,7 +1789,7 @@ l10n:p -->
 ## Database
 
 <p align="center">
-  <img src="http://i.imgur.com/Xkm5CXz.png"/>
+  <img src="images/Xkm5CXz.png">
   <br/>
   <i><a href=https://www.youtube.com/watch?v=kKjm4ehYiMs>Source: Scaling up to your first 10 million users</a></i>
 </p>
@@ -1791,7 +1798,7 @@ l10n:p -->
 ## Базы данных
 
 <p align="center">
-  <img src="http://i.imgur.com/Xkm5CXz.png"/>
+  <img src="images/Xkm5CXz.png">
   <br/>
   <i><a href=https://www.youtube.com/watch?v=kKjm4ehYiMs>Source: Scaling up to your first 10 million users</a></i>
 </p>
@@ -1837,7 +1844,7 @@ l10n:p -->
 The master serves reads and writes, replicating writes to one or more slaves, which serve only reads.  Slaves can also replicate to additional slaves in a tree-like fashion.  If the master goes offline, the system can continue to operate in read-only mode until a slave is promoted to a master or a new master is provisioned.
 
 <p align="center">
-  <img src="http://i.imgur.com/C9ioGtn.png"/>
+  <img src="images/C9ioGtn.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -1848,7 +1855,7 @@ l10n:p -->
 Ведущий сервер работает на чтение и запись, реплицируя записи на один или более ведомых серверов. Ведомый сервер работает только на чтение. Ведомые сервера могу реплицировать на дополнительные ведомые сервера (как в древовидной структуре). Если ведущий сервер перестает работать, система продолжает работать в режиме только на чтение до тех пор, пока один из ведомых серверов не станет ведущим, или пока новый ведущий сервер не будет создан.
 
 <p align="center">
-  <img src="http://i.imgur.com/C9ioGtn.png"/>
+  <img src="images/C9ioGtn.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Источник: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -1872,7 +1879,7 @@ l10n:p -->
 Both masters serve reads and writes and coordinate with each other on writes.  If either master goes down, the system can continue to operate with both reads and writes.
 
 <p align="center">
-  <img src="http://i.imgur.com/krAHLGg.png"/>
+  <img src="images/krAHLGg.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -1883,7 +1890,7 @@ l10n:p -->
 Оба ведущих сервера работают на чтение и запись и координирует операции записи между собою. Если один из ведущих серверов перестают работать, система может продолжать работать на чтение и запись.
 
 <p align="center">
-  <img src="http://i.imgur.com/krAHLGg.png"/>
+  <img src="images/krAHLGg.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Источник: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -1938,7 +1945,7 @@ l10n:p -->
 #### Federation
 
 <p align="center">
-  <img src="http://i.imgur.com/U3qV33e.png"/>
+  <img src="images/U3qV33e.png">
   <br/>
   <i><a href=https://www.youtube.com/watch?v=kKjm4ehYiMs>Source: Scaling up to your first 10 million users</a></i>
 </p>
@@ -1949,7 +1956,7 @@ l10n:p -->
 #### Федерализация
 
 <p align="center">
-  <img src="http://i.imgur.com/U3qV33e.png"/>
+  <img src="images/U3qV33e.png">
   <br/>
   <i><a href=https://www.youtube.com/watch?v=kKjm4ehYiMs>Source: Scaling up to your first 10 million users</a></i>
 </p>
@@ -1987,7 +1994,7 @@ l10n:p -->
 #### Sharding
 
 <p align="center">
-  <img src="http://i.imgur.com/wU8x5Id.png"/>
+  <img src="images/wU8x5Id.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2002,7 +2009,7 @@ l10n:p -->
 #### Шардирование
 
 <p align="center">
-  <img src="http://i.imgur.com/wU8x5Id.png"/>
+  <img src="images/wU8x5Id.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Источник: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2311,7 +2318,7 @@ l10n:p -->
 #### Wide column store
 
 <p align="center">
-  <img src="http://i.imgur.com/n16iOGk.png"/>
+  <img src="images/n16iOGk.png">
   <br/>
   <i><a href=http://blog.grio.com/2015/11/sql-nosql-a-brief-history.html>Source: SQL & NoSQL, a brief history</a></i>
 </p>
@@ -2328,7 +2335,7 @@ l10n:p -->
 #### Колоночное хранилище
 
 <p align="center">
-  <img src="http://i.imgur.com/n16iOGk.png"/>
+  <img src="images/n16iOGk.png">
   <br/>
   <i><a href=http://blog.grio.com/2015/11/sql-nosql-a-brief-history.html>Source: SQL & NoSQL, a brief history</a></i>
 </p>
@@ -2361,7 +2368,7 @@ l10n:p -->
 #### Graph database
 
 <p align="center">
-  <img src="http://i.imgur.com/fNcl65g.png"/>
+  <img src="images/fNcl65g.png">
   <br/>
   <i><a href=https://en.wikipedia.org/wiki/File:GraphDatabase_PropertyGraph.png>Source: Graph database</a></i>
 </p>
@@ -2376,7 +2383,7 @@ l10n:p -->
 #### Графовая база данных
 
 <p align="center">
-  <img src="http://i.imgur.com/fNcl65g.png"/>
+  <img src="images/fNcl65g.png">
   <br/>
   <i><a href=https://en.wikipedia.org/wiki/File:GraphDatabase_PropertyGraph.png>Source: Graph database</a></i>
 </p>
@@ -2422,7 +2429,7 @@ l10n:p -->
 ### SQL or NoSQL
 
 <p align="center">
-  <img src="http://i.imgur.com/wXGqG5f.png"/>
+  <img src="images/wXGqG5f.png">
   <br/>
   <i><a href=https://www.infoq.com/articles/Transition-RDBMS-NoSQL/>Source: Transitioning from RDBMS to NoSQL</a></i>
 </p>
@@ -2460,7 +2467,7 @@ l10n:p -->
 ### SQL или NoSQL
 
 <p align="center">
-  <img src="http://i.imgur.com/wXGqG5f.png"/>
+  <img src="images/wXGqG5f.png">
   <br/>
   <i><a href=https://www.infoq.com/articles/Transition-RDBMS-NoSQL/>Source: Transitioning from RDBMS to NoSQL</a></i>
 </p>
@@ -2510,7 +2517,7 @@ l10n:p -->
 ## Cache
 
 <p align="center">
-  <img src="http://i.imgur.com/Q6z24La.png"/>
+  <img src="images/Q6z24La.png">
   <br/>
   <i><a href=http://horicky.blogspot.com/2010/10/scalable-system-design-patterns.html>Source: Scalable system design patterns</a></i>
 </p>
@@ -2523,7 +2530,7 @@ l10n:p -->
 ## Кэширование
 
 <p align="center">
-  <img src="http://i.imgur.com/Q6z24La.png"/>
+  <img src="images/Q6z24La.png">
   <br/>
   <i><a href=http://horicky.blogspot.com/2010/10/scalable-system-design-patterns.html>Источник: Scalable system design patterns</a></i>
 </p>
@@ -2670,7 +2677,7 @@ l10n:p -->
 #### Cache-aside
 
 <p align="center">
-  <img src="http://i.imgur.com/ONjORqk.png"/>
+  <img src="images/ONjORqk.png">
   <br/>
   <i><a href=http://www.slideshare.net/tmatyashovsky/from-cache-to-in-memory-data-grid-introduction-to-hazelcast>Source: From cache to in-memory data grid</a></i>
 </p>
@@ -2701,7 +2708,7 @@ l10n:p -->
 #### Кэширование Cache-aside (кэш отдельно)
 
 <p align="center">
-  <img src="http://i.imgur.com/ONjORqk.png"/>
+  <img src="images/ONjORqk.png">
   <br/>
   <i><a href=http://www.slideshare.net/tmatyashovsky/from-cache-to-in-memory-data-grid-introduction-to-hazelcast>Источник: From cache to in-memory data grid</a></i>
 </p>
@@ -2746,7 +2753,7 @@ l10n:p -->
 #### Write-through
 
 <p align="center">
-  <img src="http://i.imgur.com/0vBc0hN.png"/>
+  <img src="images/0vBc0hN.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2777,7 +2784,7 @@ l10n:p -->
 #### Кэширование Write-through (сквозное)
 
 <p align="center">
-  <img src="http://i.imgur.com/0vBc0hN.png"/>
+  <img src="images/0vBc0hN.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Источник: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2820,7 +2827,7 @@ l10n:p -->
 #### Write-behind (write-back)
 
 <p align="center">
-  <img src="http://i.imgur.com/rgSrvjG.png"/>
+  <img src="images/rgSrvjG.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2834,7 +2841,7 @@ l10n:p -->
 #### Кэширование Write-behind / write-back (отложенная запись)
 
 <p align="center">
-  <img src="http://i.imgur.com/rgSrvjG.png"/>
+  <img src="images/rgSrvjG.png">
   <br/>
   <i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Источник: Scalability, availability, stability, patterns</a></i>
 </p>
@@ -2860,7 +2867,7 @@ l10n:p -->
 #### Refresh-ahead
 
 <p align="center">
-  <img src="http://i.imgur.com/kxtjqgE.png"/>
+  <img src="images/kxtjqgE.png">
   <br/>
   <i><a href=http://www.slideshare.net/tmatyashovsky/from-cache-to-in-memory-data-grid-introduction-to-hazelcast>Source: From cache to in-memory data grid</a></i>
 </p>
@@ -2873,7 +2880,7 @@ l10n:p -->
 #### Кэширование Refresh-ahead (предварительное обновление)
 
 <p align="center">
-  <img src="http://i.imgur.com/kxtjqgE.png"/>
+  <img src="images/kxtjqgE.png">
   <br/>
   <i><a href=http://www.slideshare.net/tmatyashovsky/from-cache-to-in-memory-data-grid-introduction-to-hazelcast>Источник: From cache to in-memory data grid</a></i>
 </p>
@@ -2932,7 +2939,7 @@ l10n:p -->
 ## Asynchronism
 
 <p align="center">
-  <img src="http://i.imgur.com/54GYsSx.png"/>
+  <img src="images/54GYsSx.png">
   <br/>
   <i><a href=http://lethain.com/introduction-to-architecting-systems-for-scale/#platform_layer>Source: Intro to architecting systems for scale</a></i>
 </p>
@@ -2943,7 +2950,7 @@ l10n:p -->
 ## Асинхронность
 
 <p align="center">
-  <img src="http://i.imgur.com/54GYsSx.png"/>
+  <img src="images/54GYsSx.png">
   <br/>
   <i><a href=http://lethain.com/introduction-to-architecting-systems-for-scale/#platform_layer>Источник: Intro to architecting systems for scale</a></i>
 </p>
@@ -3037,7 +3044,7 @@ l10n:p -->
 ## Communication
 
 <p align="center">
-  <img src="http://i.imgur.com/5KeocQs.jpg"/>
+  <img src="images/5KeocQs.jpg">
   <br/>
   <i><a href=http://www.escotal.com/osilayer.html>Source: OSI 7 layer model</a></i>
 </p>
@@ -3046,7 +3053,7 @@ l10n:p -->
 ## Взаимодействие
 
 <p align="center">
-  <img src="http://i.imgur.com/5KeocQs.jpg"/>
+  <img src="images/5KeocQs.jpg">
   <br/>
   <i><a href=http://www.escotal.com/osilayer.html>Источник: OSI 7 layer model</a></i>
 </p>
@@ -3107,7 +3114,7 @@ l10n:p -->
 ### Transmission control protocol (TCP)
 
 <p align="center">
-  <img src="http://i.imgur.com/JdAsdvG.jpg"/>
+  <img src="images/JdAsdvG.jpg">
   <br/>
   <i><a href=http://www.wildbunny.co.uk/blog/2012/10/09/how-to-make-a-multi-player-game-part-1/>Source: How to make a multiplayer game</a></i>
 </p>
@@ -3132,7 +3139,7 @@ l10n:p -->
 ### Transmission control protocol (TCP)
 
 <p align="center">
-  <img src="http://i.imgur.com/JdAsdvG.jpg"/>
+  <img src="images/JdAsdvG.jpg">
   <br/>
   <i><a href=http://www.wildbunny.co.uk/blog/2012/10/09/how-to-make-a-multi-player-game-part-1/>Источник: How to make a multiplayer game</a></i>
 </p>
@@ -3157,7 +3164,7 @@ TCP полезен для приложений, которым необходи
 ### User datagram protocol (UDP)
 
 <p align="center">
-  <img src="http://i.imgur.com/yzDrJtA.jpg"/>
+  <img src="images/yzDrJtA.jpg">
   <br/>
   <i><a href=http://www.wildbunny.co.uk/blog/2012/10/09/how-to-make-a-multi-player-game-part-1/>Source: How to make a multiplayer game</a></i>
 </p>
@@ -3178,7 +3185,7 @@ l10n:p -->
 ### User datagram protocol (UDP)
 
 <p align="center">
-  <img src="http://i.imgur.com/yzDrJtA.jpg"/>
+  <img src="images/yzDrJtA.jpg">
   <br/>
   <i><a href=http://www.wildbunny.co.uk/blog/2012/10/09/how-to-make-a-multi-player-game-part-1/>Источник: How to make a multiplayer game</a></i>
 </p>
@@ -3212,7 +3219,7 @@ UPD менее надежный, но работает хорошо для пр
 ### Remote procedure call (RPC)
 
 <p align="center">
-  <img src="http://i.imgur.com/iF4Mkb5.png"/>
+  <img src="images/iF4Mkb5.png">
   <br/>
   <i><a href=http://www.puncsky.com/blog/2016-02-13-crack-the-system-design-interview>Source: Crack the system design interview</a></i>
 </p>
@@ -3255,7 +3262,7 @@ l10n:p -->
 ### Удалённый вызов процедур (Remote procedure call, RPC)
 
 <p align="center">
-  <img src="http://i.imgur.com/iF4Mkb5.png"/>
+  <img src="images/iF4Mkb5.png">
   <br/>
   <i><a href=http://www.puncsky.com/blog/2016-02-13-crack-the-system-design-interview>Источник: Crack the system design interview</a></i>
 </p>
@@ -3691,7 +3698,7 @@ l10n:p -->
 > Articles on how real world systems are designed.
 
 <p align="center">
-  <img src="http://i.imgur.com/TcUo2fw.png"/>
+  <img src="images/TcUo2fw.png">
   <br/>
   <i><a href=https://www.infoq.com/presentations/Twitter-Timeline-Scalability>Source: Twitter timelines at scale</a></i>
 </p>
@@ -3732,7 +3739,7 @@ l10n:p -->
 > Статья о том, как спроектированы действующие системы.
 
 <p align="center">
-  <img src="http://i.imgur.com/TcUo2fw.png"/>
+  <img src="images/TcUo2fw.png">
   <br/>
   <i><a href=https://www.infoq.com/presentations/Twitter-Timeline-Scalability>Источник: Twitter timelines at scale</a></i>
 </p>