Optimal Router Settings

Network world is becoming more mainstream, but without being simplified. Thus, more and more people own or use a router at home without any understanding of its functions. The massive deployment of broadband Internet access via ADSL and permanent or cable has caused a proliferation of local network at home (or business). There are many facilities within some amount in which you need to just unpack and plug the router and miraculously, everything works the first time, at least for Internet access. However once the needs are different like for online games, telephone, access to remote machines, etc things get complicated and I receive many questions from users a little lost. Most of these facilities include a router that must understand the operating principle to configure properly.

Internet is not a network but a network of networks where the name INTER Networking. These networks are interconnected by specialized programs in this work, often integrated into an autonomous body called the router. A router has two network interfaces then to link two LANs. The Internet allows two machines to exchange information between them. Each machine has a unique IP address which allows it to be identified on the network. This address (IPv4) is a 32 bit number that is usually represented as a sequence of 4 numbers from 0 to 255 as for example, 66.94.230.34. Since this is not very practical you can use a symbolic address easier to remember such as www.google.com. Servers called DNS (Domain Name System) perform the conversion between the symbolic address and the actual physical address. To see this conversion, the simplest and typing on a command line (DOS window in W98 or XP command prompt) ping www.google.com. To find the IP address of your machine, type ipconfig on the command line.

To connect two machines on the network, TCP / IP cutout information packets that include all the IP address of the original equipment and the IP address of the destination device. If machines are on the same LAN, they communicate directly. Otherwise, packets are sent to the router. The router checks if packets are destined for the LAN interface of the other if it goes to another router until you find the router that has an interface on the local network of the destination address. Typing on the command line tracert www.google.com, you can follow the sequence of routers used to reach the destination machine, usually between 10 and 20.

To see if the IP address belongs to the local network or another network, TCP / IP needs additional information. This is provided as a mask. The usual value 255.255.255.0 defines a local network of 256 IP addresses.

Configuration settings of the TCP / IP, DHCP

You must already know the IP address and subnet mask as explained above. If the destination machine does not belong to the same LAN, you must know the local address of the router that will handle the routing of packets that parameter gateway (or gateway in English). The last parameter is the address of a DNS to convert symbolic address IP address if necessary. In summary:

• IP address and mask of the machine required.
• Gateway IP addresses necessary to access machines outside the LAN.
• IP address of a DNS needed to resolve symbolic names.

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You can configure these settings using the DHCP service if the user has configured the TCP / IP request to obtain an IP address automatically. The advantage of this service is to provide settings to automatically configure the machine. The disadvantage is that the address may vary at each startup unless we assign a static IP address in the DHCP service. This service requires a DHCP server on the LAN. The most routers, if DHCP is ON, providing that service as well as the Internet Connection Sharing built into Windows XP.

Who assigns IP addresses?

For the Internet system works, we must say that the public IP addresses are all different among the 4 billion combinations allowed by the 32 address bits. The rapid growth of the Internet beyond all expectations and use of IP for systems not connected to the Internet has made it impossible or unnecessary to assign different public IP addresses to all machines on the Internet. The IANA (The Internet Assigned Numbers Authority-body that assigns Internet addresses) has created three blocks of addresses, called private:

• 10.0.0.0 - 10.255.255.255 (10 / 8 prefix)
• 172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
• 192.168.0.0 - 192.168.255.255 (192.168/16 prefix)

These blocks of private addresses are not routed over the Internet and the use of these addresses is free within a local Internet. You can assign them as you want for your private LAN.

To best use the existing stock of public addresses, providers of Internet addresses have become used to give one public IP address accessible on the Internet in most public offerings. If you have a machine, there is no problem but when you have multiple machines, you must assign private addresses, taken in the blocks above. This solution has one major drawback: the machines with private addresses cannot communicate directly with the public Internet. We must find a trick. Many systems are possible. As always, for simplicity, I will not describe the simplest and most modern that can be used with all consumer routers: NAT also known as the masquerading under Linux

The NAT router

A router, as its name suggests, the packets it receives according to a routing table to the next router until it reaches the destination LAN. Each packet contains the source address and destination address. In the case of private addresses, the source address is a private address unknown to the Internet. The recipient cannot respond. We must therefore replace the private address of origin by a public address. It is the work of the NAT (Network Address Translation) which processes addresses. To properly configure a NAT router, you must understand the concept of port.

TCP / IP uses ports (a number from 0 to 65535) as a way to name the ends of a logical connection, a conversation with several exchanges. The port can simultaneously perform thousands of logical connections on the same IP address. They can share the Internet connection between different programs and different machines at home. As for IP addresses, IANA ranked ports in 3 categories. 0 to 1023, the Well Known ports used only by the system or associated functions, from 1024 to 49,151 in the Registered ports used by user programs from 49152 to 65535 dynamic ports or private. By default, the HTTP protocol uses port 80, POP3 port 110, etc.

When a machine on the LAN sends packets to a server outside, the source address is a private address. The recipient cannot respond to that address. To resolve this problem, the NAT router replaces the address and port of origin through the public Internet address of the router and a free port number chosen at random noting address and port associated with the local machine.

The destination machine returns the reply address and the port is visible from the Internet router NAT. It is then the inverse transformation to return the packages to the local machine. In this case, there is nothing special to configure. That's instant messaging function. The software on the machine on the private network connects to the mail server that knows well the external address and port number of the router that can contact this machine. In contrast, a machine that calls from the Internet to reach a private address is no way to do this because the router does not know which machine on the internal network must route the call. There is a way which is called port forwarding.

Port Forwarding

Port forwarding allows you to connect from the Internet to a machine that has a private address behind a NAT router unknown. We know only that the machine will process the application on a particular port, for example, port 80 for HTTP or port 110 for POP server. The port forwarding is therefore to indicate the router to retransmit packets that arrive on port 80 to the local machine hosting the HTTP server and those that arrive on port 110 to the machine that hosts the POP server. It is natural that these machines have a fixed private IP address for the router it finds. The options to configure port forwarding in the router are usually found in advanced settings configuration tool, usually a small web server built into the router.

How to be visible on the Internet

The Internet Service Providers assign you generally only one public IP address. That this address is fixed or variable, it is not easy to remember. Then you have to install a small software client on a machine on your network. This software will report every change of your public IP address to DynDNS.

Other methods of sharing an Internet connection

Other methods of sharing an Internet connection are the following: Internet Connection Sharing (ICS) or Internet Connection Sharing and Windows Server Proxy.

Internet Connection Sharing (ICS) or Internet Connection Sharing on Windows is simply the NAT is performed between two network interfaces on the machine that shares the Internet connection. A network interface is connected to the Internet with a public address and the other interface is connected to the LAN with a private address. The service also provides a mini DHCP server for automatic configuration of other machines and a local DNS proxy to relay DNS queries to the Internet.

The proxy server was the old way of providing Internet access to hosts on a private network. The proxy server that was on the private LAN, relaying requests from local machines to the Internet. Proxy server cache was also used to reduce traffic to the Internet by storing locally the pages requested by users. Finally, we also used as address filtering to limit access to certain sites. He had set the server address in his browser making it difficult to use. The function cache had a tendency to slow down operations since each machine already had its local cache and address filtering is achievable simply through a router. This mechanism has therefore been abandoned in the general public. There are still some networks as transparent proxy mode to benefit from the function cache for downloading large files.

How to Configure Hotspot Router

The configuration with a wireless router is a bit more complex than that with an Access Point. First, you must select the Wireless Router Wireless devices in the function of Preferences. At this point you must specify the IP addresses of LAN and WAN ports Wireless Router. These values are set to default to 192.168.2.1 (WAN) and 192.168.1.1 (LAN).

Here's how to configure the various network elements:

The Internet port of the Access Point Router (internet setup) must be configured in a static (Static IP) as follows:

• IP address: 192.168.2.1
• Subnet Mask: 255.255.255.0
• Gateway: 192.168.2.2 (address of the server's network adapter connected to LAN2)
• DNS: DNS server addresses of your Internet Service Provider

As for the address of the router (network setup), you should use the following configuration:

• IP address: 192.168.1.1
• Subnet Mask: 255.255.255.0
• DHCP Server: active with addresses from 192.168.1.3

Also disable any firewall, disable the NAT address or set the Access Point as a router and not Gateway.

For Example the configuration of the Linksys 54G Wireless Router (supplied by Softvision preconfigured):

To access the router must use a browser and connect to the 192.168.1.1 page. Access shall be from a computer that has the network adapter configured to automatically obtain the IP address or a type 192.168.1.x. The computer must be connected to one of the LinkSys 4-port switch, or via WI-FI (so the configuration cannot be done by the server).
The access routers will require a username and password: leave blank User Name field and use admin for password. At this point, Basic Setup screen will appear. Obviously instead of the DNS that appear in the previous screen, will be included as an ISP. To set the device as a router, you should go to the Advanced Routing page and set the heading Operating Mode to Router.

Finally, if you want you can change the name of the Access Point. (For example, "Name of the local hotspots"). This setting can be made in the section under the heading Wireless Wireless Network Name (SSID).

Network adapters on the Server

The configuration of the first network card (the one connected to the modem) is identical to the case of the Access Point, while the network adapter connected to LAN 2 will be set as follows:

• IP address: 192.168.2.2
• Subnet Mask: 255.255.255.0
• Default Gateway: no value

Regarding the configuration of the modem router connected to a LAN, may be appropriate to use the same settings on all.

VPN Router

The first step is to connect the router to the mains and connect via the bundled cable, one of the inland port router (LAN interface) with a network card on the computer from which you will configure. Next, mount comes in a flat network cable to the WAN interface of the router.

After performing these steps, make sure that the indicator of signal presence on the WAN interface is showing signs of life. If at this stage is successful, then you can start configuring the software. For a start (in the case of Windows XP) go to Control Panel and select Network Connections. In network connections, locate the icon Local Area Connection, click it right mouse button and select Properties.

In the next window in the list of components the Internet Protocol (TCP / IP) and run on it, double-click, and then opens the Internet Protocol (TCP / IP). In this window you should set the automatic acquisition of protocol parameters and to confirm the changes.

Next, start your browser, then in its address bar, type 192.168.0.1 and press Enter to go to the address.

As a result, you will get an invitation to the router in the figure below. For entry into the internal menu of the router you will need to enter your username and password. If no settings previously on the router were not made, it will be sufficient to only specify the user name (default - admin) and click on OK.

Once you get into the inner menu router, you can immediately go to the point of Home – WAN. It should first configure the router to Static mode IP Address.

To do this in the field, store the parameters of the protocol TCP / IP:

• IP Address - the value of the IP address of your contract (unique in each case)
• Subnet Mask - is the same for all value (255.255.255.0)
• ISP Gateway Address - meaning the default gateway of the contract (the same for all users on one network segment)
• Primary DNS Address - same for all value (10.10.250.250)
• Secondary DNS Address - same for all value (10.10.140.250)
• MTU - packet size (leave default)
• After entering the required data, click on Apply

In this menu, you will need to configure the router to work through PPTP VPN. Consider all the points from top to bottom:

• Leave the switch in the position of Static IP
• My IP Address - meaning the IP address of your contract (unique in each case)
• My Subnet Mask - is the same for all the value of the subnet mask (255.255.255.0)
• My Gateway - the value of the default gateway of the contract (the same for all users on one network segment)
• Server IP / Name - address of the VPN server
• PPTP Account - A unique name for login to the server statistics (from the treaty)
• PPTP Password - Password for the server statistics (of contract)
• Retype Password - Confirm password
• Connection ID - connection name (optional)
• Maximum Idle Time - leave default
• MTU - leave the default
• Connect Mode Select - select Always-on (included permanently), or Connect-on-demand
• Auto-backup - leave default
• After filling all the necessary options, click on Apply

Now we can proceed in the top menu item - Status and in the field information on the state WAN interface to find the value of the external router's MAC address. This value the need to provide technical support to the router was able to earn in our network. After successful registration, the MAC address you can try clicking on the button Connect (3) and look at the status of the connection just above the button itself.

On successful connection will indicate the status of PPTP Connected. If the router consistently failed to connect to the server, you should check the correctness of all of the previous two steps to configuring and correctness of registration on the network by MAC address. When the item is successful, then you are ready to configure routing so that when the VPN compound were available local network resources.

Some Tips

How do I connect the router to the Internet to a computer or different peripheral devices and how to configure the router so that it functions fully implemented quickly and smoothly. These and other similar questions often arise in the mind of the novice computer user who just bought a new router. First: read all instructions on connecting. Only pre-acquainted with her, you will be able to properly find all the ports in the router, you will be able to properly install the router and ensure it is compatible with various peripheral devices work.

Second: Connect all the cables to the appropriate ports in the router - this is mentioned in great detail in the relevant sections of the instructions. And only after that turn it into a network. Normally the operating system itself finds the connected device. Once the connection is completed the router, proceed to the immediate installation of the router and its fine-tuning to the existing local network. To configure the router / modem and network cards there are special instructions: You can use any address space assigned statically or DHCP server in the router. An interesting feature of this configuration is that the server need not be present in the local network but can also be a remote type.

It may be that your router is reluctant to run the first time out of the box (oh the joys of computing). In this case, do not panic, we remove everything and start again. Turn off the computer, unplug the ADSL modem and router. This being done, be sure to keep to a minimum connection of the router. Unplug all cables except the ADSL modem and main PC. Turn on / plug in the order: router, modem and computer.

Verify that you can access the interface of your router from your browser (http://192.168.1.1 or http://192.168.2.1 or more depending on model). If it works, you can configure your DSL connection in the interface and connect your PC via Ethernet, if necessary.

Many time a simple detection of the router from your computer works. In this case there are some very simple steps to follow. Generally, the problem is a conflict of IP addresses that your computer is programmed to use a different IP slice of that used by the router. In this case the first thing to do, assuming that your router's DHCP client is very active is to click Start > Control Panel. Go to the application Network Connections > by a clever double-click. You should see several icons appear symbolizing network connections. We select the icon Local Area Connection and then made a clever right-click and finally click on Properties. Under This connection uses the following items: click on Internet Protocol TCP / IP then click properties. A new dialog box appears: On the General tab, click Obtain an IP address automatically and then click Get DNS server address automatically "and click OK first and second time.