FreeBSD is an open source, Unix-like operating system that provides features such as multitasking, memory protection, and multi-user facilities. It is used by many companies including IBM, Nokia, Apple, and Netflix to build products and operating systems. FreeBSD has a monolithic kernel and uses a 1:1 threading model. It supports processes, files systems with directories and files, and memory management using paging and swapping. FreeBSD also supports network communication using multiple protocols and allows file sharing between clients and servers using NFS. Security features include SSL, TLS, access control lists, and mandatory access controls developed by the TrustedBSD project.

1. FreeBSD
Sindh Madressatul Islam University
Spring 2017
4th Semester

2. HISTORY
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3. INTRODUCTION
• FreeBSD is an open source.
• It is Unix-like operating system.
• It provides all the features, such as
preemptive multitasking, memory
protection, virtual memory, multi-user
facilities etc.
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4. USES
• It Uses many IT companies: IBM, Nokia
to build their product.
• Certain parts of Apple’s Mac OS operating
system are based on FreeBSD .
• PSP3 operating system also borrows
certain components from FreeBSD.
• Netflix, what’sapp are also examples of
big, successful companies which are
running FreeBSD 10.
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5. TARGET
• Desktop
• Server
• Embedded Systems
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6. DESIGN PRINCIPLE
There are several design principles of
FreeBSD:
• The design of the system should be as
simple as possible.
• Security mechanism should be open for
the public.
• All access to the system should be
carefully checked.
• The separation of logical and physical
environment is needed to reduce the
possible risks.
• It Should be user friendly.
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7. KERNEL MODULE
• FreeBSD has a monolithic kernel.
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8. KERNEL THREADING
• Kernel threading was first introduced in
FreeBSD 5.0, by using an M:N
threading model. It is also called hybrid
model.
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9. KERNEL THREADING
Implementation of M:N kernel model
worked, but it did not perform well, so that
FreeBSD started using a 1:1 threading
model in version 7.0.
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10. PROCESS MANAGEMENT
BSD supports a multitasking atmosphere.
Each task or thread of execution is termed a
process. The context of a BSD process
comprises of user-level state, with the
contents of its address space and the run-
time environment, and kernel-level state,
which includes scheduling limits, resource
controls, and identification information.
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11. FILE SYSTEM
The file system forms a tree, the beginning of
which is the root directory, sometimes referred to
by the name slash, spelled with a single solidus
character (/). The root directory contains files, it
contains vmunix, a copy of the kernel-executable
object file. It also contains directories, it contains
the user directory. Within the user directory is
the bin directory, which mostly contains executable
object code of programs, such as the files Is and vi.
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12. MEMORY MANAGEMENT
BSD uses a two-level approach to maintain available
resources.
1. If a modest amount of memory is available, the
system will take memory resources away from
processes if these resources have not been used
recently. Should there be a severe resource
shortage, the system will resort to swapping the
entire context of a process to secondary storage.
2. The demand paging and swapping done by the
system are effectively transparent to processes. The
support of large sparse address spaces, mapped
files, and shared memory was a requirement for
BSD. An interface was specified, called mmap, that
allowed unrelated processes to request a shared
mapping of a file into their address spaces
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13. LANGUAGE CODE
In order to localize a FreeBSD system to a
specific language, the user needs to find out
the codes for the language. The following
are examples of language.
Language Code Description
en_US English - United States
ru_RU Russian for Russia
zh_TW Traditional Chinese for Taiwan
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14. NETWORK COMMUNICATION
BSD could provide interoperability and resource
sharing among the diverse set of machines that
was available in the Berkeley environment.
Consequently, the network-communication layer
is designed to support multiple protocols. New
protocols are added to the kernel without the
support for older protocols being affected. Older
applications can continue to operate using the
old protocol over the same physical network as
is used by newer applications running with a
newer network protocol.
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15. FILE SHARING PROCESS
• FreeBSD supports the Network File System
(NFS), which allows a server to share directories
and files with clients over a network.
• With NFS, users and programs can access files
on remote systems as if they were stored locally.
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16. FILE SHARING PROCESS
NFS has many practical uses. Some of the common
uses are:
• Data that would otherwise be duplicated on
each client can be kept in a single location and
accessed by clients on the network.
• Several clients may need access to
the userdirectory. Sharing that directory allows
for quick access to the source files without
having to download them to each client.
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17. SECURITY PROTOCOL
Free BSD uses Security Protocols are
• SSL (Secure Sockets Layer).
• TLS (Transport Layer Security).
These protocols provide a secure communications
layer over which other protocols can be utilized.
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18. SECURITY PROTOCOL
• FreeBSD provides several security-related
features including access control lists (ACLs),
security event auditing and mandatory access
controls (MAC).
• These security enhancements were developed
by the Trusted BSD project. The project was
founded by Robert Watson with the goal of
implementing concepts from the Common
Criteria for Information Technology Security
Evaluation.
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19. SECURITY PROTOCOL
The project is supported by a variety of
organizations, including the
• NSA, Network Associates Laboratories.
• Yahoo!.
• McAfee Research.
• Apple Computer.
• Google.
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20. USER INTERFACE
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21. THANK YOU
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