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Posts Tagged ‘firewall’

Iptables – Keep Some Rules on Your Mind While Installing Iptables!

January 7th, 2012 No comments

http://www.xenocafe.com/tutorials/linux/redhat/iptables/images/Image8.pngIptables is an application program that enables a system administrator to organise the tables offered by the Linux Kernel firewall. Various Kernel modules and programs are in use for different protocols.

Iptables will fail to function if it was not executed by root user and it also needs to elevated privileges to operate. Iptables can be installed on most of the Linux system.  To refer to the kernel level components Iptables is also commonly used. There is some overlap in early history about iptables and Netfilter because they were initially designed together. Iptables is one of the latest application programs that have been specially designed to configure the Linux Kernel release.

Iptables preserve the basic ideas introduced with ipfwadm.  The spilt enables iptables to use the information the connection tracking layer had determined about a packet. Iptables has the ability to monitor the state of a connection. Users can get many benefits by using iptables application program on their system.

The users don’t have to worry about the installation process of iptables. It is very simple to install. User can use application program like iptables to make their task easier. While you are trying to install iptables on your system you should keep some rules in your mind. It is very important to realise packet filtering deals with the protocol packets, however is actually meant to apply to the sessions as well as is intended to decide whether & how the client processes may make use of the server processes and server processes will support the client processes.

Lots of issues in configuring the iptables are consequence of aim to define the fairly high level of policies that are related to the client or server interactions when making use of mechanism, which deals with lowest levels of these interactions, the individual packets.  iptables configuration needs first defining plans at level of the sessions, and figuring out which of the rules enforce these policies on the packets traveling between the interfaces; this needs an ability to conceptualize how the agents like the user and process as well as actions like the web browsing map on the lower level entities such as interfaces & packet attributes. It is as well useful to do reverse, which is given the iptables configuration for inferring what type of the policy it can end up to implement.

Categories: Security Tags: ,

Basic Linux security for beginners – Provide Security for Beginners!

January 6th, 2012 No comments

Security is one of the major problems for the internet users today. It is affects every user in their smooth work. It is a big concern for the user if you are using Linux operating system.  Although Linux is one of the best operating system but there are some concern about the security issue of Linux operating system, especially for beginners. Therefore, it is necessary for beginners to know the procedure to keep their system secure enough for safe usage. One of the best things you can do to secure your system by stay aware about the security concern.

If you are a beginner then you have to know some security tips to protect your computer from any type of damage.  As a beginner you don’t have to be a security guru to be safe but you have to know some basic thing to safe your system. You have to understand the principles of the TCP/IP protocol before knowing something about security. Tcp and udp are the two parts of TCP/IP protocol. The main difference between tcp and udp is the tcp is connection oriented but the udp is connectionless. Both tcp and udp have several advantages and disadvantages and they both are used differently. The traditional UNIX systems encrypted users’ passwords using algorithm named salt+crypt and after that stored then the results in /etc/passwd file, On the login, system will take login password, encrypt that in same way as well as compare that with entry in /etc/passwd. In case, two agreed, then user was been considered authenticated. Solution to first problem was to switch to stronger encryption algorithm.

There are 2 problems with this and first, there is fact that, whereas salt+crypt is one-way algorithm (and you will not decrypt contents of /etc/passwd) it is not strong, as well as is limited to 8 character passwords. Worse, file /etc/passwd needs to get readable by users, as that relates the user ID numbers to names, and locates home directories as well as has other information regarding the users. It makes vulnerable to the so called dictionary attacks, where attacker takes dictionary (many systems have for the spell checking), encrypts each word in that, and after that compares them against encrypted passwords in /etc/passwd. While match is found, attacker just looks up corresponding word in dictionary & this is password.

http://i.ytimg.com/vi/Kys3y9NQqNs/0.jpg

Categories: General, Security Tags: ,

Firewalls, Switches, Routers and VPN – It’s All About Selecting the Best Networking Device!

September 21st, 2011 No comments

This time almost everyone wants to bring more customers’ attraction for their business. It can be possible through a secure networking device. However, selecting one of the best networking business is a risky job. So, you need to look for these networking systems like firewalls, switches, routers and VPN through which you can easily start your business.

There are so many users using these genres of networking systems for their business. It is the right option for you to get one of the best networking systems from online media. Let’s look for these networking systems like switches and routers and their function which are briefly discussed at the online media.

Cisco RV042 features six fast Ethernet ports and it supports around 50 separate simultaneous VPN, the Virtual Private Network for the telecommuters & branch offices connections. Cisco VPN software also includes the built in firewall & optional viruses, spam, as well as malware protection, which can help to keep the business safe.

That received actually solid customer reviews in Amazon where you may order at the discount. EtherFast Cable or DSL Firewall Router with the 4 Port Switch or VPN Endpoint is a perfect solution to connect the group of the PCs, like Small Office or Home Office, to the high speed broadband connection or 10/100 Ethernet backbone.

So, everything is upgraded to the Gigabit, probably the couple eight ports and three or so five port switches unless I would like to add more of drops to the rooms. Any suggestions on 5 & 8 port Gigabit switches? As for server, they are using that mostry as the file server, however will need RAID 0+1 on that.

I am planning on running the Server 2008 Foundation and maybe Win7 Pro 64 on it as they may not have to use that as the domain server – they are staying in the workgroup. What are pros and cons of the Server 2008 Foundation and Win 7 Pro? They will need a server to stay the ftp server for the clients for sending them the large files.

Categories: General Tags: , ,

Firewalls, Switches, Routers and VPN – Easy

July 25th, 2011 No comments

If you want to use firewalls, switches, routers and VPN networking systems, then you need to understand the basic functionalities of these genres of networking systems. Firewalls are used to strike more secure and safety network from a less secure network.

Switches are the hardware networking systems that are designed to use at layer of the OSI model data link. Routers are essential part of the Internet protocol. So, you need to collect information about the basic functionality of these networking systems before you use them. VPN is commonly known as Virtual Private Network. It is a secure way to connect a local area connection without losing data.

Layer three is Network Layer where the IP works & Layer 4 is a Transport Layer, where the TCP & UDP function. Lots of firewalls now have the advanced up OSI layers and will also know Layer 7 –Application Layer. There are various different kinds of the firewalls as well as we will not go in that in the article thus let us talk about most famous kind of the firewall – the stateful packet inspection hardware firewall.

Most of the firewalls will keep the track of states of the TCP to stop the unwanted traffic from Internet to enter the private LAN. FL mGuard line is a ideal solution to add the higher level “Layer 3”

FL mGuard products are been rugged, rated security industrially devices whose the core functions include routing, stateful firewall, VPN and NAT’ing.  Making use of FL mGuard RS lets migration of tasks that were solely once in realm of IT 19” rack closer to industrial application. Line includes the FL mGuard RS rail mount versions and PCI card versions for the integration in the industrial PCs.  RS line has the variants that includes the router version, and versions with the integrated analog modems and ISDN connections.  Three key applications for FL mGuard products are:

  • Secure remote connectivity
  • NAT router applications
  • Industrial network security

 

Categories: Security Tags: ,