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Static Vs Dynamic IP Address

An Internet Protocol (IP) address is a numerical identifier that is assigned to every device or machine in a computer network. If you are planning to start your own Internet business, using a virtual private network VPN or VOIP, you need to be adequately informed about IP addressing. We all (should) know – there are static and dynamic IP addresses. But when should you use them?

What is a Dynamic IP Address?

A dynamic IP address changes each time you boot your machine or network device. It also changes when you dial into your Internet service provider. Some ISPs change your IP each time you log on to their network while some make the changes periodically.

Most dynamic IP addresses are assigned using the Dynamic Host Configuration Protocol (DHCP). The router on your home network assigns IP addresses to your computers and other network devices as you put them on. Private IP addresses usually have this format: 192.168.0.x. Your router's IP address will usually be 192.168.0.1 while your computers will be assigned numbers ranging from 192.168.0.2 to 192.168.0.254.

In situations where you need to remotely administer a particular computer on a network, you may need to reserve a particular address for it. To assign static IPs to certain computers and dynamic IPs to others on the same network, you should reserve the IPs for the specific machines on the DHCP server. This will help you to administer the network centrally without the need to assign static IPs manually. It will also prevent the occurrence of IP conflicts.

When Should You Use Dynamic Ips?

Dynamic IPs will be good for anyone who uses their computer or home network for the following:

* To browse the Internet and upload or download files
* To send and receive email through a mail server or via a web based email service like yahoo mail, hotmail or gmail.
* To use online chat services or instant messaging
* To use FTP servers or web servers that only require access from your LAN or corporate network but do not require access from the Internet.




What is a Static IP Address?

A static IP address is a fixed IP address that is manually assigned to a device on a network. It is called a static IP because it is not changed each time the device is switched on. Static addresses remain the same each time you connect to the network or send a message.

When Should You Use a Static IP?

Static IP addresses provide greater reliability for applications such as voice over Internet protocol (VOIP). If you run a service that permits incoming audio or video, you may need to use a static IP. For example if you have an on-site IP-PBX, you will need to have at least one static IP address.

A static IP will also be required if you have a machine that functions as a server and requires external access from the users online. This includes running a web server, e-mail server, FTP server, or DNS server. A static IP allows you to enjoy faster upload speeds which boost the efficiency of these services.

If you intend to host a gaming website or you want to use Play Station, X-Box or a VPN to provide secure access to files from your corporate network server, you should also consider buying a public static IP address.


How to Set Up a Static IP in Linux?

Here are the steps you should take to assign a static IP address on a Linux system.

1. Make sure you are logged on as root
2. Create a backup copy of the /etc/network/interfaces file on your machine. You can easily restore the backup if something goes wrong.
3. Edit the /etc/network/interfaces file. From the text console, you can load this file into the famous vi editor.
4. Scroll down the file until you locate the network interface card. An Ethernet connection is usually identified by eth0 or wlan0 while a wifi connection is identified as wifi0.
5. Replace “ iface eth0 inet dhcp “ with “ iface eth0 inet static “.
6. Add these lines: (you can replace the address and dns nameserver with your own configuration)

address 192.168.0.5
netmask 255.255.255.0
network 192.168.0.0
gateway 192.168.0.0
dns-name-servers 216.10.119.241


If you are running Slackware or Red Hat Linux, one of the simplest methods is to log on as root and then type ifconfig/netstat at the console. You can then use the text-based menu to modify the configuration settings.

In Slackware the settings will take effect instantly. But in Red Hat you need to type “ service network restart “ and press enter.

 

 

Please DON'T SPY me anymore: High Level E-mail Cryptography with GnuPG

Unless you have no life, don't watch the news, and don't care about others snooping around your secrets, you are well aware that these days the government's favorite activity is spying and monitoring their people from all sides, by all means, with no scruples and no remorse, possibly including yourself.

Even if you do have a life, do watch the news, and do care about others snooping around your secrets, you certainly use one of those free popular e-mail accounts that boast of their awesome unlimited features without realizing that they are the ones that are secretly stabbing you on the back and violating your privacy.

It was because of such things that our team wrote a book on advanced e-mail security with cryptography and we want to share it with you. In this book you'll get the following benefits:

  • Awareness: you will understand how things work and never be fooled again.
  • Privacy: no one will spy your e-mails anymore, your communications will remain private.
  • Security: if your e-mails ever get compromised, no one will be able to decipher and read them.
  • Credibility: you will demonstrate to others how much you care about your privacy and your security, as well as theirs.
  • Flexibility: the system can be implemented anywhere, from home to business to mobile devices.
  • Power: high level military grade cryptography being developed for more than 15 years.
  • Freedom: 100% free/libre software based on an open standard, open source, no spyware, no malware, no viruses, nothing.
  • Cost: completely free - gratis - you won't have to buy or pay for any software.

The book is short, full of images and graphics and easy to understand. It was written for laypersons, so anyone can follow it and do the required steps very easily.

And how about the price? Well you'll love that part: you can get and share the book for free, no hidden fees or registration required, you pay how much you want for it. That's it, that's how we work, you only pay if you like.

If you like it we suggest a contribution of $10.00, the price of a decent cappuccino cup. We put a lot of effort to write it and it took a long time to be finished, so if you like it we would very much appreciate a $10.00 contribution from you.

You can get a copy of the book right here in our official website: https://goldencontest.wordpress.com

Are you still not convinced? We are giving you 10 reasons why this book will benefit you. It is called "The 10 most common mistakes people make when using e-mail". Here they are:

  • MISTAKE 1: I use a popular e-mail provider
  • MISTAKE 2: I think only the recipients can read my messages
  • MISTAKE 3: When I empty the trash bin I believe my messages were erased forever
  • MISTAKE 4: I think it is great that my e-mail account is free
  • MISTAKE 5: I own my own messages, they are mine
  • MISTAKE 6: I think cryptography is unecessary
  • MISTAKE 7: I don’t care about what the NSA is doing
  • MISTAKE 8: I think my messages are safe
  • MISTAKE 9: I trust my e-mail provider
  • MISTAKE 10: I believe I have privacy online

You can find the detailed description of all those mistakes in our website, as well as how to correct them.

Check out our website now and get a copy of our book for free. You will not only get a book, you will also get your security and privacy back.

Thanks!

The Golden Keys Team
https://goldencontest.wordpress.com

 

Physical Security Market is Expected to Reach USD 125.03 Billion Globally in 2019

The worldwide market for physical security was valued at USD 48.05 billion in 2012 and is projected to reach the market size of USD 125.03 billion by 2019, growing at a CAGR of 14.9% during the period from 2013 to 2019. Some of the major factors driving the demand for physical security include rising global security concerns and increasing budget allocations for physical security by governments to prevent terrorism and crime activities. In addition, regulations imposed by governments of different countries demanding increased security levels is driving the adoption of physical security in several end-user sectors including industrial and business organizations. Continued investments in infrastructure worldwide, especially, in Asia Pacific region is expected to emerge as a significant factor behind the growth of physical security market in coming years.

global-physical-security-market-size-and-forecast-2011-2019

The primary concern in physical security is the protection and prevention in order to serve security interests of people, equipment, and property. The increase in incidences of terror activities and crime has resulted in escalated demand for physical security solutions. It is expected that internet protocol (IP) video, sophisticated access control systems and biometric solutions would drive the demand for physical security solutions. Further, the emerging trend of convergence of logical and physical security and increased demand for integrated physical security solutions are expected to boost the growth of physical security market.

The different components of physical security include hardware, software and services. The market for physical security hardware has been further segmented into intrusion detection and prevention systems, access control systems and others (fire and life safety, visitor management and backup power). Among intrusion detection and prevention hardware products, video surveillance was the largest market and held around 72% share in 2012 and is expected to be the fastest growing segment throughout the forecast period. In access control segment, biometric access control held the largest market share of around 38% of total access control market in 2012. Physical security software market has been segmented into physical security information management (PSIM) and management, analysis and modeling software. PSIM is fast gaining market demand, driven by declining costs, increased sophistication and increasing awareness among end-users. Physical security services market has been segmented into video surveillance as a service (VSaaS), remote management services, technical support, public safety answering point (PSAP), security consulting, public alert, customer information and warning systems and others (data source, hosted access control, managed access control, alert notification, mobile security management). Among the services segments, VSaaS is expected to be the fastest growing market driven by benefits such as cost savings, simplicity, and remote access.

End-user segments of physical security include transportation and logistics, government and public sector, control centers, utilities/energy markets, fossil generation facilities, oil and gas facilities, chemical facilities, industrial (manufacturing sector excluding chemical facilities), retail, business organizations, hospitality and casinos and others (stadiums, educational and religious infrastructure, healthcare organizations). Transportation industry which includes aviation, rail, ports, road and city traffic and new start projects (including light rail, rapid rail, metro rail, commuter rail, bus rapid transit, and ferries) in transportation and logistics sector was the largest end-user of physical security in 2012. North America emerged as the largest regional market for physical security in 2012. In view of high terrorism incidences, the region has been increasing security measures across all end-use verticals. Moreover, governments in North America have significantly increased the regulatory measures for adoption of physical security. Asia Pacific is one of the fastest emerging markets for physical security, growing at a CAGR of around 17% owing to significant push from governments and the police to enhance security in view of increasing crime and terror in the region.

The market for physical security was highly fragmented in 2012 and no single player was dominant; however, Honeywell Security Group emerged as the market leader, accounting for around 5% share in 2012. Honeywell Security group was followed by Bosch Security Systems Inc, Morpho SA (Safran), Hikvision Digital Technology, Assa Abloy AB, Axis Communication AB, Pelco Inc, Tyco International Ltd, NICE Systems Ltd, and others.

 

Source : http://www.transparencymarketresearch.com/physical-security-market.html

 

REGULAR EXPRESSIONS SPECIAL CHARACTERS EXPLAINED

Regular expressions” (often shortened to “regex”) is a language used to represent patterns for matching text. Regular expressions are the primary text-matching schema in all text-processing tools, including grep,egrep,awk ,sed.

Read more in ...in website link

 

How To Install Tomcat 7 Server on CentOS/RHEL 5/6

Apache Tomcat is an opensource webserver product of Apache Foundation like Apache HTTP server. It is used to deploying Java Servlet and JSP applications. To deploy any application in Tomcat we can simply create a war fileand deploy them. For more details about you can visit apache official site.

 

Continue to following article to Install Apache Tomcat 7 on CentOS/RHEL Servers.  

 

Cantata 1.3.0 Music Player Released with 87 Fixes [Ubuntu Installation]

Cantata, a Qt-based music player for MPD (Music Player Daemon), has reached version 1.3.0 just yesterday, and a fix for compiling it in KDE, 1.3.0.1, was put out a few moments ago. This release comes with 87 fixes and improvements. Some major changes and new features include:

  • add option to control start-up state: visible, hidden or remembered from previous run
  • undo/redo support for play queue
  • many interface fixes and improvements
  • add remove duplicates functionality to playlists and play queue
  • read lyrics from the LYRICS tag in FLAC, Vorbis, Opus and Speex files

cantata_kdeapps01
Image source: Image credit

Overall, Cantata suffered major overhauls on all levels. The interface has suffered lots of fixes and improvements; communication with MPD was improved too; playlist and play queue handling also suffered fixes.

cantata_kdeapps02
Image source: Image credit

Installing Cantata 1.3.0 in Ubuntu 13.10

Installing from the PPA
Open the terminal and type the following commands to install Cantata from the PPA:

sudo add-apt-repository ppa:ubuntuhandbook1/cantata
sudo apt-get update
sudo apt-get install cantata

Installing from Source
Make seems to give the following error on Ubuntu 13.10 with Cantata 1.3.0 (this was fixed in Cantata 1.3.0.1):

lconvert: could not exec '/usr/lib/i386-linux-gnu/qt4/bin/lconvert': No such file or directory
make[2]: *** [translations] Error 1
make[1]: *** [po/CMakeFiles/translations.dir/all] Error 2
make: *** [all] Error 2

However, the binary is successfully built, available in the build directory and you can run Cantata as ./cantata.

Cantata 1.3.0.1 was released few moments ago with a fix for compiling it. Follow the next steps:

Download the source tarball from here and uncompress it:

tar -xjf cantata-1.3.0.1.tar.bz2

Next, install the dependencies:

sudo apt-get build-dep cantata

You will need the source repositories enabled for this to work.

Finally, change the working directory to cantata-1.3.0.1 and type the commands:

mkdir build && cd build
cmake ..
make
sudo make install

To install as normal user in a different prefix, use this:

mkdir build && cd build
cmake .. -DCMAKE_INSTALL_PREFIX=$HOME/usr
make
make install

Cantata offers a wealth of options, as well as Internet services like Jamendo and support for podcasts:

cantata03

 

Linux: Log Suspicious Martian Packets / Un-routable Source Addresses

A Martian packet is nothing but an IP packet which specifies a source or destination address that is reserved for special-use by Internet Assigned Numbers Authority (IANA). You can log packets with un-routable source addresses on Linux operating system. This tutorial explains how to log spoofed packets on Debian / Ubuntu / CentOS / RHEL / Linux based server.

Linux: Log Suspicious Martian Packets / Un-routable Source Addresses

 

Need a Good Bitcoin Client?

Bitcoin is a decentralized peer-to-peer payment system and digital currency that is powered by its users with no central authority, central server or middlemen. Instead, managing transactions and issuing money are carried out collectively by the network. Bitcoin is controlled by all Bitcoin users around the world.

To provide an insight into the quality of software that is available, we have compiled a list of 5 highly promising Bitcoin clients. Hopefully, there will be something of interest here for anyone who wants ease of use, security and advanced features.

[url=http://www.linuxlinks.com/article/20140216030924430/BitcoinClients.html]Read more[/url]

 

Cutting-Edge New Virtualization Technology: Docker Takes On Enterprise

Docker’s new container technology is offering a smart, more sophisticated solution for server virtualization today. The latest version of Docker, version 0.8, was announced couple of days ago.

Docker virtualization

Docker 0.8 is to focus more on quality rather than on features, with the objective of targeting the requirements of enterprises.

According to the software’s present developmental team; many companies that use the software have been using it for highly critical functions. As a result, the aim of the most recent release has been to provide such businesses top quality tools for improving efficiency and performance.

What Is Docker?

Docker is an open source virtualization technology for Linux that is essentially a modern extension of Linux Containers (LXC). The software is still quite a young initiative, having been launched for the first time in March 2013. Founder Solomon Hykes created Docker as an internal project for dotCloud, a PaaS enterprise.

The response to the application was highly impressive and the company soon reinvented itself as Docker Inc, going on to obtain $15 million in investments from Greylock Partners. Docker Inc. continued to run their original PaaS solutions, but the focus moved to the Docker platform. Since its initiation, over 400,000 users have downloaded the virtualization software.

Google (along with couple of most popular cloud computing providers out there) is offering the software as part of its Google Compute Engine though still nothing from major Australian companies (yes, I’m looking at you Macquarie).

Red Hat also included it in OpenShift PaaS as well as in the beta version of the upcoming release Red Hat Enterprise Linux. The benefits of containers are receiving greater attention from customers, who find that they can reduce overheads with lightweight apps and scale across cloud and physical architectures.

Containers Over Full Virtual Machines

For those unfamiliar with Linux containers, they are called the Linux kernel containment at a basic level. These containers can hold applications and processes like a virtual machine, rather than virtualizing an entire operating system. In such a scenario the application developer does not have to worry about writing to the operating system. This allows greater security, efficiency and portability when it comes to performance.

Virtualization through containers has been available as part of the Linux source code for many years. Solaris Zones was pioneering software created by Sun Microsystems over 10 years ago.

Docker takes the concept of containers a little further and modernizes it. It does not come with a full OS, unlike full virtual machines, but it shares the host OS, which is Linux. The software offers a simpler deployment process for the user and tailors virtualization technology for the requirements of PaaS (platform-as-a-service) solutions and cloud computing.

Docker images

This makes containers more efficient and less resource hungry than virtual machines. The condition is that the user must limit the OS host to a single platform. Containers can launch within seconds while full virtual machines can take several minutes to do so. Virtual machines must also be run through a hypervisor, which containers do not.

This further enhances container performance as compared to virtual machines. According to the company, containers can offer application processing speeds that are double than virtual machines. In addition, a single server can have a greater number of containers packed into it. This is possible because the OS does not have to be virtualized for each and every application.

The New Improvements and Features Present In Docker 0.8

Docker 0.8 has seen several improvements and debugging since its last release. Quality improvements have been the primary goal of the developmental team. The team – comprising over 120 volunteers for the release – focused on bug fixing, improving stability, and streamlining the code, performance boosting and updating documentation. The goals in future releases will be to keep the improvements on and increase quality.

There are some specific improvements that users of earlier releases will find in version 0.8. The Docker daemon is quicker. Containers and images can be moved faster. It is quicker building source images with docker build. Memory footprints are smaller; the build is more stable with fixed race conditions. Packaging is more portable for tar implementation. The code has been made easier to change because of compacted sub-packaging.

The Docker Build command has also been improved in many ways. A new caching layer, greatly in demand among customers, speeds up the software. It achieves this by eschewing the need to upload content from the same disk again and again.

There are also a few new features to expect from 0.8. The software is being shipped with a BTRFS (B-Tree File System) storage driver that is at an experimental stage. The BTRFS file system is a recent alternative to ZFS among the Linux community. This gives users a chance to try out the new, experimental file system for themselves.

A new ONBUILD trigger feature also allows an image to be used later to create other images, by adding a trigger instruction to the image.

Version 0.8 is supported by Mac OSX, which will be good news for many Mac users. Docker can be run completely offline and directly on their Mac machines to build Linux applications. Installing the software to an Apple Macintosh OS X workstation is made easy with the help of a lightweight virtual machine named Boot2Docker.

Docker may have gained the place it has today partly because of its simplicity. Containers are otherwise a complex technology, and users are traditionally required to apply complex configurations and command lines. Docker makes it easier for administrators, with its API, to easily have Docker images inserted in a larger workflow.

It is currently being developed as a plug-in that will allow use with platforms beyond Linux, such as Microsoft Windows, via a hypervisor. The future plans for the developmental team is to update the software once a month. Version 0.9 is expected to see a release early in March, 2014. The new release may have some new features if they are merged before the next release, otherwise they will be carried over to the next release.

Docker is expected to follow Linux in numbering versions. Major changes will be represented by changing the first digit. Second digit changes signify regular updates while emergency fixes will be represented by a final digit.

Customers looking forward to the production ready Docker version 1 will have to wait until April. They can also expect support for the software as well as a potential enterprise release. There are also attempts by the team to develop services for signing images, indexing them and creating private image registries.

Give it a try!

 

Basic Use of 'ls' Command With Examples for Beginners

One of the most used commands by Linux users and the one that a Linux beginner must learn is- 'ls' Command. It is usually used to view the contents of current directory. So, when you run this command, the files and sub-directories included under the current directory will be listed before you. Very useful command and everyone who uses Linux should know this command.

This article will guide you to know more about 'ls' command with it's basic usages. Here we start !

Read More at YourOwnLinux.

 

Understanding INODES in Linux/Unix Filesystems

The inode ( also known as Index Node) is a very basic concept related to Linux and UNIX filesystem. Each and every object/element in the filesystem is associated with an inode.

        You must be aware of the fact that, most of the countries have given a unique identity to their citizens in the form of a unique identification number ('Aadhar Card' in India and 'SSN' in the USA) to identify an individual easily and uniquely. This also leads to make all the paper work corresponding to any citizen easier to be handled.
    Just like these identification numbers for people, there is a unique identity of every member of a Linux filesystem which is known as Inode number and it uniquely exists for each and every individual file on Linux or Unix filesystems.

Read more at YourOwnLinux.
 
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