Does anyone know what is port forwarding?

Question

Quote router has two ip addresses. It has the external ip address, and an internal ip address Quot

What is the external IP address the IP address the ISP gives you?And the internal IP address the gatway?

Answer 1

An external IP address is the IP address assigned to a user (typically a home user) by an ISP which is the address "seen" by the world of the Internet. This is set apart from the Internal (non-routable) "private" IP address, used internally only to route data around a home.



For example, an external IP address could be 76.101.44.212 and this would not feature at all in the internal home network. Instead, the home network would be based upon the private (non-routable) network, 192.168.1.1, of which there might be: a home desktop computer, 192.168.1.10, a laptop, accessing the home network, 192.168.1.13, and a wireless NIC attached to the family TiVo (and updating the family's television programming), 192.168.1.65 etc... Many more devices could be added, typically up to four wired devices and multiple wireless devices, depending on the protocol used, and whether it is 802.11 b, g or n. None of these devices could be accessed over the routable IP network, 76.101.44.1, except via the family router, which by using NAT (Network Address Translation) passes the data packets to the internal network.



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A gateway is a network point that acts as an entrance to another network. On the Internet, a node or stopping point can be either a gateway node or a host (end-point) node. Both the computers of Internet users and the computers that serve pages to users are host nodes, while the nodes that connect the networks in between are gateways. For example, the computers that control traffic between company networks or the computers used by internet service providers (ISPs) to connect users to the internet are gateway nodes.



In the network for an enterprise, a computer server acting as a gateway node is often also acting as a proxy server and a firewall server. A gateway is often associated with both a router, which knows where to direct a given packet of data that arrives at the gateway, and a switch, which furnishes the actual path in and out of the gateway for a given packet.



On an IP network, clients should automatically send IP packets with a destination outside a given subnet mask to a network gateway. A subnet mask defines the IP range of a network. For example, if a network has a base IP address of 192.168.0.0 and has a subnet mask of 255.255.255.0, then any data going to an IP address outside of 192.168.0.X will be sent to that network's gateway. While forwarding an IP packet to another network, the gateway might or might not perform Network Address Translation.



A gateway is an essential feature of most routers, although other devices (such as any PC or server) can function as a gateway.



Most computer operating systems use the terms described above. A computer running Microsoft Windows however describes this standard networking feature as Internet Connection Sharing; which will act as a gateway, offering a connection between the Internet and an internal network. Such a system might also act as a DHCP server. Dynamic Host Configuration Protocol (DHCP) is a protocol used by networked devices (clients) to obtain various parameters necessary for the clients to operate in an Internet Protocol (IP) network. By using this protocol, system administration workload greatly decreases, and devices can be added to the network with minimal or no manual configurations.



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Port forwarding or port mapping is the technique of forwarding a TCP/IP packet traversing a network address translator (NAT) gateway to a predetermined network port on a host within a NAT-masqueraded, typically private network based on the port number on which it was received at the gateway from the originating host.



The technique is used to permit communications by external hosts with services provided within a private local area network



Port forwarding allows remote computers, for example, computers on the Internet, to connect to a specific computer or service within a private local area network (LAN).



In a typical residential network Internet access is obtained through a DSL or cable modem connected to a router or network address translator (NAT). Hosts on the private network are connected to an Ethernet switch or communicate via a wireless LAN. The NAT device's external interface is configured with a public IP address. The computers behind the router, on the other hand, are invisible to hosts on the Internet as they each communicate only with a private IP address.



When configuring port forwarding, the network administrator sets aside one port number on the gateway for exclusive use of communicating with a service in the private network, located on a specific host. External hosts must know this port number and the address of the gateway to communicate with the network-internal service. Often, the port numbers of well-known Internet services, such as port number 80 for web services (HTTP), are used in port forwarding, so that common Internet services may be implemented on hosts within private networks.

Answer 2

The router has an external IP address. This is the address the internet sees. Think of this as the address to an apartment complex.



Your personal network has a bunch of internal address. usually starting with 192.168.1.X or 10.10.X.X. This is only used on your network. This of this as your apartment number inside the complex. The router's internal ip address is the gateway, meaning this is the address to send information that needs to be sent to the internet.



When you access the network your computer sends a the message to the router (with your internal ip address), who then sends it out to the internet. When it does this it overwrites your internal Ip address with its own ip address so the destination (internet) knows where to send the reply (back to the house). The reply is received by the router and the router looks up who sent the last message to that destination. The message is then routed back to your internal ip address.



port forwarding is needed when this is not the sequence of events (such as games). It is not always a send message -> reply format. sometimes you just get messages (like from a game). your router needs to know what to do with these messages. port forwarding tells the router that any message coming in on a certain port should be automatically forwarded to your internal ip address.

Answer 3

Yes the external is the IP address the ISP gives your router. The Internal IP address is that which you assign to your computer or XBox or whatever. Usually the router assigns the IP addresses to your internal devices but if you want to port forward to something, it's best that you assign in manually so that it never changes. The internal address of the gateway itself is its Ethernet address as seen by your computers and such. It is usually 192.168.1.1.

Answer 4

The external address is the public address issued by your ISP. The internal address is the router LAN address, also the default gateway for all the computers using the connection. Port forwarding really has nothing to do with either. It is the method of allowing public access to an internal machine on your network. It involves choosing whatever service you want to make public, like a web server etc, and then selecting which machine you want to point the service to.

Answer 5

The router ought to grant dynamic IP addressing for as much as 254 gadgets linked to it the two by wireless or ethernet cable. i think the disaster is that probable the main units, quite often the computer that knocks out the different gadgets has its community configuration set to a particular fastened ip handle instead of 'motor vehicle', that conflicts with what the router iss giving to a diverse device. confirm that the community configuration of all the units are set to ask for an ip handle from the router and do not have a fastened one fixed.