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IP Masquerade is a networking function in Linux similar to the one-to-many (1:Many) NAT (Network Address Translation) servers found in many commercial firewalls and network routers. For example, if a Linux host is connected to the Internet via PPP, Ethernet, etc., the IP Masquerade feature allows other "internal" computers connected to this Linux box (via PPP, Ethernet, etc.) to also reach the Internet as well. Linux IP Masquerading allows for this functionality even though these internal machines don't have an officially assigned IP address . MASQ allows a set of machines to invisibly access the Internet via the MASQ gateway. To other machines on the Internet, the outgoing traffic will appear to be from the IP MASQ Linux server itself. In addition to the added functionality, IP Masquerade provides the foundation to create a HEAVILY secured networking environment. With a well built firewall, breaking the security of a well configured masquerading sys...

in our tour of duty, we are facing another case where the ethernet device on motherboard didn't recognize by linux kernel. here are the specification : motherboard  : GIGABYTE G41MT-S2PT linux operating system :   Scientific Linux 6.0 another enterprise-based linux (centos, oracle linux) will works (i hope). we have try with fedora 14 , but it didn't recognize the device and the driver is not available yet. fortunate we have found the driver in binary (RPM package). first download the package file from the following links : i386 driver : kmod-atl1e-1.0.1.14-1.el6.elrepo.i686.rpm x86_64 driver : kmod-atl1e-1.0.1.14-1.el6.elrepo.x86_64.rpm step 1 install the package by typing  (as root) rpm -ivh kmod-atl1e... .rpm step 2 change directory to /etc/sysconfig/, please check whether there is a file called network, if there isn't create new file with your favourite text editor. cd /etc/sysconfig/ vim network the content of network file : NETWORKING=...

Network Address Translation Network Address Translation (NAT) is the process where a network device, usually a firewall, assigns a public address to a computer (or group of computers) inside a private network. The main use of NAT is to limit the number of public IP addresses an organization or company must use, for both economy and security purposes. The most common form of network translation involves a large private network using addresses in a private range (10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, or 192.168.0 0 to 192.168.255.255). The private addressing scheme works well for computers that only have to access resources inside the network, like workstations needing access to file servers and printers. Routers inside the private network can route traffic between private addresses with no trouble. However, to access resources outside the network, like the Internet, these computers have to have a public address in order for responses to their requ...