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Mozilla Firefox Architecture Vs. Chromium ArchitectureMozilla Firefox Architecture Vs. Chromium Architecture

“ software application for retrieving, presenting, and traversing

information resources on the World Wide Web”

Wikipedia

• Bring information resources to the user for a given URL.

• Handle Uniform Resource Identifier• Direct prefixes that the browser cannot handle to

another application.• Identify the web page content and display the

information• Identify unsupported file types and direct user to

download them.

Mozilla FirefoxMozilla Firefox is a free and open source web browser developed and maintained by Mozilla foundation. Firefox is the second most widely used browser in the world.

Chromiumchromium is the open source web browser project from which Google Chrome draws its source code..

• supports tabbed browsing, which allows users to open several pages in one window.

• Integrated customizable download manager is also included

• Remember user history and Data

• Both Firefox and Chrome relies on the extension system.

It follows layered architecturalStyle. Each layer below providesServices to upper layer

PIPE AND FILTER

Master slave design pattern is used. Where Masters are located at Network Service Package and slaves are other subsystems such as protocol handler

Gecko is responsible for getting data from Necko subsystem and converting them into a viewable form.

For that it gets services from other components such as data persistence , display

backend .. Etc. In Rendering and browser

engine there are 6 components such as document Parser, Content Model, Frame Constructor, Image Library, Style System and Platform Specific Rendering and Widgets

Security of the Mozilla is implemented using the component Personal Security manager

• Personal security manager gets services from NSS and provides security services to the client.

• NSS provides open source libraries to be reused by the client applications and tools to manage keys and security models.

• Crypto functions are set of public functions that perform cryptographic operations

• Multiple instances of Rendering Engine will be used at the same time• The browser kernel is responsible for managing multiple instances of

the rendering engine and for implementing the browser kernel API• Rendering engine uses WebKit opens source layout engine for the

rendering process• Chromium browser users a separate optimized JavaScript engine called

V8 instead of inbuilt JavaScript capabilities of WebKit to increase the speed

Rendering engine

Rendering engine

JavaScript Engine

V8V8

JavaScript Engine

V8V8ExtensionsExtensionsPluginsPlugins

Browser KernelBrowser Kernel

NetworkNetworkViewsViews

DataData

Brings operating systems’ separate process architecture in to the browser.Use separate processes for browser tabs to protect the overall application from bugs and glitches in the rendering engine (i.e. A malfunction in a single tab does not affect the overall stability of the browser)

Main process that runs the Main process that runs the UI and manages tab and UI and manages tab and plugin processes as the plugin processes as the

"browser process". "browser process". Likewise, the tab-specific Likewise, the tab-specific

processes are called processes are called "render processes" "render processes"

Two major components•Browser kernel (high privileged) – interacting with OS, data persistence, network access. Subjected to OS level security barriers•Rendering Engine (low privileged) - Chromium uses a modular architecture that places the complex rendering engine in a low-privilege sandbox

Chromium hope to reduce the severity of vulnerabilities by isolating a browser’s complex components by adding layers of defense and reducing

their privileges.

Plugins are created by third party vendors. They cause many security vulnerabilities and instabilities. Sandboxing can not be used here because they are not designed to run in Chromium’s sandboxed architecture.

To compromise security, stability and usability solution is to run each plugin as separate process. Rendering engine instances will communicate with them through IPCs

Advantages of running each plugin as a separate process•Each plugin is run with users privileges. This improves usability (e.g. the Flash Player plug-in can use the user's microphone and webcam)•Crash of a plugin does not affect over all browser stability

Vendors could write future versions of plug-ins that operate within Chromium's sandbox, to provide greater defense against plug-in exploits.

• Chromium's separate process architecture and it’s V8 JavaScript engine makes it fast

• Firefox maintains threads for each search instance. So that chrome has become more faster.

• Because of different rendering processes and plugin processes in chrome error in a rendering task or browser plugin does not affect the stability of the overall browser

• Firefox has a disadvantage in this case because if one plugin crashes it affects all other pages. Electrolysis project is underway to introduce process based browsing.

• Chromium's sandbox architecture protects browser kernel and OS from malicious codes

• Firefox onion architecture for cryptographic operations protects main crypto code in Personal Security Manager.

• Separate process architecture in chromium uses more memory and CPU.

• Firefox has its own advantage in this case. Because it uses one single process and memory consumption is very low comparing to chrome.