How to Configure a RouterOriginal Polish version by Lukasz SawickiProper configuration of the router is the precondition for networking and Internetaccess. Lets begin with the description of its functions. In general, router is anetwork device that is a communication node between the sending and receivingendpoint. The control of the traffic is called routing. Router creates a routing table orrouting information base (RIB) that stores the best routes to certain networkdestinations, or the "routing metrics" associated with those routes, and the path tothe next hop router. It allows to direct the packets to specified destinations. Therouting process means interaction of at least two subnets.The immense growth of the number of Internet users is the reason of remedialmeasures that overcome the limits of Ipv4 (Internet Protocol version 4). One of themeasures is routing. It means linking of internal network with a pool of "private" IPaddresses to the public network. Simply the router uses less (external) IP addressesthan the number of supported computers in the local network. The diagram belowdepicts the typical solution.Example of routing with NAT functionRouter configuration example is based on theTP-Link TL-WR340G deviceNotice: TP-Link TL-WR340G N2952 does not support ADSL service (it is not
equipped with ADSL modem).Router/Cisco routers connects two or more logical subnets, e.g. external networkwith Internet access (WAN) with local network (LAN), making a bridge forinformation exchange. Without proper configuration the connection would beimpossible. In most cases, router acts as a specialized computer (replacing a standardcomputer) working in external network, with software and hardware tailored to thetasks of routing and forwarding. It allows to create internal (local) network.In this case, the computer configuration involves: taking down all settings of the NIC (working in external network), o IP address o Subnet mask o Default gateway o Preferred DNS server changing the way of address assignment to dynamic (DHCP), or setting fixed IP address from the routers range, connecting the computer with LAN port of the router.Example of assigning a fixed IP address for TCP/IP protocol. This option is used whenthe router does not assign addresses automatically. At this stage there is no need toenter default gateway nor DNS servers parameters.After restarting the computer, there is possibility of connecting with the router (viaInternet browser). The logged in user (the initial user name and password are given
in the users manual) can configure the router.The login windowThe easiest way of configuring the router is use of "Quick Setup" option.The first dialog boxTo begin configuration we should choose Next.It is important to select adequate kind of WAN connection type:There are three possibilities: PPPoE - in the case of network using PPPoE protocol (rather untypical), Dynamic IP - the router will get IP address automatically (the most common option), Static IP - in the case of fixed IP address.
Choice of WAN connection typeFor Static IP option there are needed the settings of the NIC (to be entered). In thecase of Dynamic IP this box will be omitted:After configuring WAN port parameters the next step is setup of Access Point:Planning to use access point, it is needed: to select suitable channel, to set SSID, to choose the region (country), to set data encryption and cryptographic keys (in the tab Wireless >> Wireless Settings).
Access Point setup boxIt is important to choose adequate region:Region selection box
Information on successful completionIt should be remembered that the addresses of the internal LAN have to be differentfrom that of the WAN port (the same address would cause instability e.g. auto-resetof the router). For example, with IP address of WAN 192.168.1.1, the LAN networkcan be addressed 192.168.(not 1).1, or in quite different range, e.g. 188.8.131.52.To set LAN parameters we enter Network >> LAN:LAN address setupSome ISPs identify the user by the MAC address of the NIC. To keep it unchanged(after exchanging the NIC port for the routers port) we use MAC Clone option(Network >> MAC Clone):MAC Clone optionIn the DHCP >> DHCP Settings box there is possibility of setting DHCP serverparameters. With such configuration of the DHCP server the local computers canobtain their IP addresses automatically. It is a very convenient solution.
Example configuration of DHCP serverTo ensure security of WiFi network it is needed to employ data encryption and assigncryptographic keys, in the Wireless >> Wireless Settings box.Currently the best security level in home WLANs is provided by WPA2-PSK encryption (seebelow):
Advanced settings of Access PointIt is indispensable to change the default passwords in the administrator panel (System Tools >>Password). On the Internet there are active programs which try to log in to routers of the usersthat have forgotten to do so:
Change the default password !In the Status window we may preview all the settings:Status windowIt is reasonable to save the configuration data:
System Tools >> Backup &Restore Configuration.More Notes:More guides, news and tips of routers, switches, firewall security and other popularnetwork hardware you can visit: http://blog.router-switch.com/