Freecom Technologies FSG-3 manual Network Address Translation, Hosting a server

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Appendix

Network Address Translation

GB

When you visit a website via your computer, your router, or more specifically your NAT, remembers which computer on the internal network asked for the information. When the information (in this case the website you asked for) comes back, the router knows which computer on the internal network to send the information to. This is Network Address Translation or NAT.

Developed by Cisco, Network Address Translation is used by a device (firewall, router or computer) that sits between an internal network and the rest of the world. For more information about IP address translation, refer to RFC 1631, The IP Network Address Translator (NAT).

Hosting a server

What If I want to host a server?

For others to be able to view your pictures on your computer, you need to run some type of service or server. A web server such as apache will allow others to securely watch the pictures or files on your site. But how does the NAT of your router know this time to which computer to forward the information?

Since the request comes from the internet, most routers are setup to disallow any traffic going into the internal network. (Firewall protection) In this case, since we want people to be able to see our pictures, we want the router to forward this information. We have to tell the router to do this.

Someone calling from the internet asks your router for a certain "port". This is the same as someone calling the receptionist and requesting a certain person by name. Ports are displayed as numbers but invariably map to pre described services. For instance, when someone requests a web page, they always ask for the service on port 80, the web server. Through NAT, it is possible to "map" a certain request for a service (a request for a port) to a certain PC on the internal network.

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Contents Freecom FSG-3 Storage Gateway Freecom Technologies Germany CongratulationsChapter Contents of the box General InformationTechnical Support Freecom on the net Related Publications Statement of ConditionsTrademarks System Requirements Hardware RequirementsSoftware Requirements Precautionary measures FSG-3 connectors, LEDs and buttons Getting to know your FSG-3FSG-3 Front panel FSG-3 Back panel Possible Connections with your FSG-3Booting LED configurationPower LED Power Sync Button LED Front Panel LEDsBack Panel LEDs 1Installing the required Network Components Configuring Windows 98 SE, and Me to work with the FSG-3Before you begin Preparing Your Computers to connect to the FSG-3Before you begin 2Assign your TCP/IP configuration by DhcpConfiguring Windows XP, NT or 2000 to work with the FSG-3 Selecting Internet Access MethodVerifying TCP/IP Properties Installing or Verifying Windows Networking Components MacOS MacOS 8.6 orVerifying TCP/IP Properties Macintosh Getting on the internetInternet configuration information Login ProtocolsAccount Information Obtaining ISP Configuration Information Windows Ready for Configuration Obtaining ISP Configuration Information MacintoshRestarting the Network How to Install Hardware InstallationInstall from the Application CD How to start the FSG Assistant Freecom Storage Gateway AssistantFSG Assistant functions Configure basic settings of your Freecom Storage Gateway Setup the DSL account on your Freecom Storage GatewayBrowse available folders on your Freecom Storage Gateway Add a new printer Start recovery procedureSearch again for available Freecom Storage Gateway devices How to reach the configuration menu ConfigurationAdmin Http//192.168.1.1Changing the administrator password WAN or internet connection setupFirst steps Connecting the hardware Setting up the FSG-3FSG-3 WAN port connected to a router Configuration FSG-3 WAN port connected to a modem Admin account Setting up users, groups and foldersSet the Date and Time 2The guest accountCreating a new account Setting up multiple connection methodsCreating a new group Creating a new folderFull potential Configuration options explained InformationSystem Information Device Information Version Information4Network Information WAN PortLAN Port Log files Hardware menu Save ConfigurationRestore Configuration Date & Time Reset ConfigurationHard drive menu Spin down timeHard disk format Update Firmware FSG Health ServicesDhcp Server Options DescriptionDynamic DNS OptionsDescription Http Server SSH Server FTP ServerPort Forwarding Users SecurityUser Groups Adding a new user Options DescriptionFolders Adding a new groupConnections AdministratorAdding a new folder LAN connectionWAN Connection WAN Options Add a connection Virtual Private NetworksAdministrator for more info Shutdown and reboot menu RebootShutdown Logout Accessing the FSG-3 from Windows Freecom Storage Gateway AssistantManual mapping Mac OS X v10.3.x and higher Accessing FSG-3 Data from Mac OSSmb//192.168.1.1 Smb//FSGNAMEFreecom FSG-3 Storage Gateway USB Mass storage installation Attaching external USB devicesUSB external device information USB Printer Installation Power2File systems Attaching external USB devices Clear Printer Job Queue Filesystems Attaching external S-ATA devicesTroubleshooting Basic FunctioningPWR LED Not On Troubleshooting the Web Configuration Interface TroubleshootingObtaining a WAN IP Address Troubleshooting the ISP ConnectionTroubleshooting PPPoE Troubleshooting Internet BrowsingTroubleshooting a TCP/IP Network Using a Ping Utility Wrong network configuration Testing the LAN Path to Your GatewayTesting the Path from Your PC to a Remote Device Wrong physical connectionsRestoring the Default Configuration and Password Using the Default Reset buttonProblems with Date and Time Support Persistent problemsCE, FCC and other certification AppendixCertificate of the Manufacturer/Importer Firmware source codeVoluntary Control Council for Interference Vcci Statement GPL StatementNetworks and Routing Basics What is a Router?Basic Router Concepts Routing Information ProtocolInternet address classes Domain Name ServerClass a Class BClass E Class E addresses are for experimental use NetmaskEquals Subnet Addressing IP address shortage Multiple internal but only one external IP address DhcpHosting a server Network Address TranslationMAC Addresses and Address Resolution Protocol Ethernet CablingCable Quality Technical specifications Technical specificationsWarranty valid in Europe/Turkey only