Linux comes with a host based firewall called Netfilter. The netfilter is a set of hooks inside the Linux kernel that allows kernel modules to register callback functions with the network stack. A registered callback function is then called back for every packet that traverses the respective hook within the network stack. This Linux based firewall is controlled by the program called iptables to handles filtering for IPv4, and ip6tables handles filtering for IPv6. I strongly recommend that you first read our quick tutorial that explains how to configure a host-based firewall called Netfilter (iptables) under CentOS / RHEL / Fedora / Redhat Enterprise Linux. If you are using Ubuntu/Debian Linux, see how to setup UFW for more info. This post lists most simple iptables solutions required by a new Linux user to secure his or her Linux operating system from intruders. [continue reading…]
Embedded Linux is the use of a Linux operating system in an embedded computer systems such as a mobile phones, personal digital assistants, media players etc.
This tutorial shows you how to install Linux on a target system. Not a prebuilt Linux distribution, but your own, built from scratch. While the details of the procedure necessarily vary from one target to another, the same general principles apply. The result of this tutorial (if you have a suitable target) is a functional Linux system you can get a shell prompt on.
In this tutorial, you will learn about:
Discussion of cross-compilation issues
Review of the components of a Linux system and how they are put together
Detailed steps for building, installing, and configuring the target system
Great information on how to install Fedora Linux on PS3. This is 3 part series.
Part 1 the Sony PlayStation 3 (PS3) runs LinuxÂ®, but getting it to run well requires some tweaking. In this article, first in a series, Peter Seebach introduces the features and benefits of PS3 Linux, and explains some of the issues that might benefit from a bit of tweaking.
Part 2 of this series discusses getting the latest PS3 addons installed and updated on your system, and some of the configuration changes you can make to reduce the basic memory footprint until you’ve got a bit of breathing room.
Part 3 in this series looks at what you can do to get a usable X environment for doing simple graphical work, without losing the ability to run the compiler.
Free software foundation (GNU project) has published a list of 5 reasons to avoid Apple iPhone 3G. According to article Apple puts so many restrictions on you including privacy and DRM limitations:
 iPhone completely blocks free software. Developers must pay a tax to Apple, who becomes the sole authority over what can and can’t be on everyone’s phones.
 iPhone endorses and supports Digital Restrictions Management (DRM) technology.
 iPhone exposes your whereabouts and provides ways for others to track you without your knowledge.
 iPhone won’t play patent- and DRM-free formats like Ogg Vorbis and Theora.
 iPhone is not the only option. There are better alternatives on the horizon that respect your freedom, don’t spy on you, play free media formats, and let you use free software — like the FreeRunner.
NETGEAR launches Open Source edition of wireless-G router enabling Linux developers, geeks, hackers and enthusiasts to create Firmware for specialized applications
Open Source Wireless-G Router (WGR614L) delivers higher processing power and more memory for a Wide Variety of customized applications. The product is supported by a dedicated and responsive open source community.
The high-performance WGR614L, which is “Works with Windows Vista” certified, features a 240 MHz MIPS32 CPU core with 16 KB of instruction cache, 16 KB of data cache, 1 KB of pre-fetch cache, and incorporates 4 MB of flash memory and 16 MB of RAM. In addition to an external 2 dBi antenna, the WGR614L integrates a second internal diversity antenna to provide enhanced performance and range. The router supports free open source Linux-based Tomato and DD-WRT firmware and will soon support OpenWRT.
The WGR614L is supported by a dedicated open source router community at myopenrouter.com.
Open source – free to install any firmware
Hotspots, guest access via a separate SSID
Upstream and downstream QOS and intelligent bandwidth monitoring
One 10/100 Internet WAN port and a four-port 10/100 LAN switch
802.11g access point (54 Mbps).
Static and dynamic routing with TCP/IP, VPN pass-through (IPSec, L2TP), NAT, PPTP, PPPoE, DHCP (client and server), and Bigpond.
A Stateful Packet Inspection (SPI) firewall
Support for 40-, 128- and 152-bit WEP encryption, Wi-Fi Protected Access (WPA), WPA2-PSK, and Wi-Fi Protected Setup (WPS).
Additional security features include DMZ, MAC address authentication, URL content filtering, logs and e-mail alerts of Internet activity.
Moblin.org is an open source community for sharing software technologies, ideas, projects, code, and applications to create an untethered computing experience across Mobile Internet Devices (MIDs), Netbooks, and embedded devices.
Now, Intel and Wind River Systems have teamed up to create a Linux/x86 platform for car electronics, which will debut at the Telematics Detroit 2008 conference today (May 20). The offering is based on Intel’s low-power Atom processor and a new variant of Wind River’s embedded Linux.
Wind River announced that its Linux Platform for Infotainment, optimized for Intel’s Atom, should be available in August. It will include speech-recognition and speech-to-text software from Nuance Communications, Bluetooth and noise reduction from Parrot, music management from Gracenote, networking from SMSC and DVD playback from Corel.
The software will provide connectivity with Apple iPods and support 3D interfaces. It will also support the Controller Area Network and Media-Oriented Systems Transport buses used to link electronics in many cars.
Linux can be used a real time operating system ( RTOS ) for thermostats, household appliance controllers, mobile telephones, industrial robots, spacecraft, industrial control and scientific research equipment.
Linux is not only a perfect platform for experimentation and characterization of real-time algorithms, you can also find real time in Linux today in the standard off-the-shelf 2.6 kernel. You can get soft real-time performance from the standard kernel or, with a little more work (kernel patch), you can build hard real-time applications.
This article explores some of the Linux architectures that support real-time characteristics and discusses what it really means to be a real-time architecture. Several solutions endow Linux with real-time capabilities, and in this article author examine the thin-kernel (or micro-kernel) approach, the nano-kernel approach, and the resource-kernel approach. Finally, author describe the real-time capabilities in the standard 2.6 kernel and show you how to enable and use them.
Linux comes with many serial text and gui based serial communication programs. My favorite is minicom – friendly menu driven serial communication program.
If you are addicted to DOS / Windows TELIX (a telecommunications program originally written for DOS and was released in 1986), minicom is for you under Linux / UNIX.
minicom Common features / usage
=> Setting up a remote serial console
=> Access a computer / server if the LAN is down
=> Connect to embedded Linux / BSD device via null modem cable
=> Connect to Cisco routers for configuration
=> Connect to dump device i.e. device w/o keyboard and mouse
=> Dialing directory with auto-redial
=> Support for UUCP-style lock files on serial devices
=> Separate script language interpreter
=> Capture to file
=> Multiple users with individual configurations
Let us see how to configure minicom for my Soekris net4801 Single Board Computer / embedded Linux device. [continue reading…]
Ubuntu’s latest release, Gutsy Gibbon, now includes support for the embedded and mobile spaces with the Ubuntu Mobile and Embedded (UME) project. Get to know the UME project, and find out how to get started. The primary objective of this tutorial is to get you quickly acquainted with the Ubuntu embedded framework and tools. Along the way, you learn about several tools and new approaches to Linux kernel configuration and environment construction. You also learn about some other projects with goals similar to the UME project.
Introduction to the Ubuntu Mobile and Embedded (UME) project, its architecture, and its use
How to install and test the Hildon desktop
How to build a development environment for a mobile device