I have a socket application which I can use in local network, at home.
I can make them communicate for example from 192.168.x.x to 192.168.y.y ip addresses.
What should I do if I want to use the application over internet, from a remote machine, not local. For example which ip addresses should I use if my friend who lives another country wants to access my application.
On the server end, the easiest way is to bind to all available addresses by using IPAddress.Any as the address. You'll need to give the client your public Internet address to connect to. If you're being a NAT, it might involve looking at your router for the address (or using http://www.whatismyip.com/) and configuring it to route the traffic to your PC.
You need to set up your router to forward the port that you wish to communicate on. Once you have that in place, give your friend your public IP address.
For instance, you can configure your router rules to point all port 80 requests to your 192.168.x.x machine, so that when ever a request for port 80 comes in, it automatically gets sent to a specific address on your subnet.
Your outgoing IP address. Use this site to see it: http://www.whatismyip.com/
And of cause port forward your router.
You will have to use the IP address provided by you ISP (internet service provider). Usually these IP addresses are non static, so that you need to provide some way to resolve your dynamic IP address to a static name (dyndns providers do this usually).
In addition you need to configure you router to forward the incomming traffic on port xxx to your local machine (this is usually not your router, except when you are using a modem). This is called port forwarding.
Related
Here is my situation :
I have a WCF with TCP Binding Service behind NAT and I am not able
to reach it.
I can reach my service using BasicHttpBinding and Raw TCP Sockets.
At server side port forwarding is done.
What may cause this ?
My Network Topology: Picture Link
I'm not experienced with WCF and nettcpbinding but this could help.
Theoretically it is not possible because your service has a local IP address, corresponding to the LAN where it is attached, and not a public IP address. So it could not be reached from the Internet, outside the NAT. However, almost all NAT devices, maybe your router/Access Point, have a feature for "Port Forwarding". This feature allows you to define that all packets addressed to a specific port are forwarded to a specific machine within you LAN, with a private IP address.
This could be a solution for you if you can overcome two hinders:
1-I don't know how the node in the Internet will send a message to the callback server. If it uses the IP address from which it received the request, there is not problem. If it receives a callback-IP address, then you have to figure out how to find out the public IP address of you NAT (maybe router/Access Point) and send out that IP address.
2-Your service behind a NAT needs to open a client port, or ephemeral port, to communicate with the service outside the NAT. If the second sends the message to the client port from which it received the message, you have to find a way to determine the client port you want to open (must be the same you configured in port forwarding). Will it listen in port 808 by default?
I hope this helps.
Check with URI "net.tcp://0.0.0.0:8000", this will ensure that the service will accept connection from any inbound IP address. At server side, the IP address mentioned in the URI & address from which the connection is accepted differs so the server is dropping the connection.
In a website I need to store visitor's IP address for security logging. I m not sure about IP address and its details just have an idea there are different types of IP addresses like user, internet provider, LAN IP, WAN IP etc.
I am even not sure which IP address I should store in database for security I have searched and came to know about Request.UserHostAddress that it returns The IP address of the remote client.
Can you please guide and confirm if I am sotring correct IP and using correct code to retrive IP ?
Edit
I am not certain why IP address is stored but know just as a good practice to do it. My guess is IP need to be stored to identify user, just in case if something wrong happens, with stored IP address it can be traced out who did it or from what area this request came.
Is there some other use of IP, please direct me as well.
Cheers
IP stands for Internet Protocol, which is the protocol underlying HTTP, which is what clients use to connect to web servers. Every machine on an IP network has a unique IP address.
UserHostAddress is the correct property for identifying the client's IP address. It does not matter whether the client is coming from the LAN or WAN, nor does it matter who their internet provider is. Internet providers (and I'm simplifying here) help route traffic to your website, but don't actually participate as an endpoint; the ISP's servers will not show up in the UserHostAddress, only the actual client who initiates the connection, which is typically the user.
Note that I say typically. IP addresses can be spoofed, or they can be hidden behind a proxy (like TunnelBear) or other obfuscation system (like Tor). There's no way to guarantee that you have the "real" IP address of the "real" user, but the aforementioned property is the closest you're going to be able to get.
I need to assign a unique IP address (local) for a device we will be connecting into our system via. USB. The actually assigning I will do over RS232 (don't ask!) by telling the device what it's IP is.
I would like to somehow find a usable address relative to the local PC in order to tell the device which to use. Is there a way of enumerating or finding a usable address in C#? I don't want to simply use a fixed one in case of possible clashes with other devices.
I've done a search here and there's lots of people wanting to find the current IP, or the IP of an already existing device, but I can't find much about generating a usable, unique one.
Thanks for any assistance you can give me.
Assigning static IP addresses (even if you ping them) is a bad idea.
What happens if the IP address you've assigned is to a device that happens to be offline right now?
Use DHCP if you can, and consider prompting the user if you can not retrieve an IP address from DHCP as to what it should be assigned to.
I am not ware of a native C# library for DHCP client's, but using pinvoke will get you what you're after. Example code (not tested) here, http://www.ianatkinson.net/computing/dhcpcsharp.htm
From http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol
The Dynamic Host Configuration Protocol (DHCP) is a network
configuration protocol for hosts on Internet Protocol (IP) networks.
Computers that are connected to IP networks must be configured before
they can communicate with other hosts. The most essential information
needed is an IP address, and a default route and routing prefix. DHCP
eliminates the manual task by a network administrator. It also
provides a central database of devices that are connected to the
network and eliminates duplicate resource assignments. In addition to
IP addresses, DHCP also provides other configuration information,
particularly the IP addresses of local Domain Name Server (DNS),
network boot servers, or other service hosts. DHCP is used for IPv4 as
well as IPv6. While both versions serve much the same purpose, the
details of the protocol for IPv4 and IPv6 are sufficiently different
that they may be considered separate protocols.[1] Hosts that do not
use DHCP for address configuration may still use it to obtain other
configuration information. Alternatively, IPv6 hosts may use stateless
address autoconfiguration. IPv4 hosts may use link-local addressing to
achieve limited local connectivity.
Ok, not really sophisticated or anything, but why don't you just try to ping the ips, starting by the lowest, and pick the first one which doesn't respond?
I wanted to learn how networking in c# works, so I learned how to use TCP server and clients.
The only problem is that it's working only if both computers are connected to the same network..
How can I make them communicate even if they aren't?
TCP/IP sockets should work between any two end points as long as there is a route between them. If there is no route between them then you are talking about a case where there are two separate disconnected networks. In that case you will need something to bridge the two networks.
If you are using TCP/IP server/client communication and the computers are on different networks that has a route connecting them and they cannot communicate then you should look at firewall settings and other network settings to make sure TCP/IP packets from one network are able to reach the other network.
Make sure you are using the correct IP address when the client tries to connect to the server. If you have a server at IP address 10.0.0.5 listening on port 4823 try to telnet to that IP address from the client using the server IP address 10.0.0.5 and port 4823. If it connects that usually means that you have things set up right.
From a command prompt: telnet 10.0.0.5 4823
Communication in TCP is done with IP addresses. So even if the client and the server are not on the same network if you specify the IP address of the server, the client will be able to communicate with it (assuming of course the network that the client resides on is configured properly and knows how to reach the server's network). You could also use the DNS service and provide the FQDN of the server instead of an IP address. The DNS server on the client network will resolve the server's FQDN to an IP address.
Is it true that, if I want to make an IP spoofing program, I need only a program that can change my machine IP address?
If true how can I use System.Net - IPAddress Class to set the ip address?
No, it is not true. Changing your machine's IP address is not IP spoofing. IP spoofing is when you create network packets that have a source IP address that does not match the actual IP address of the source machine.
http://en.wikipedia.org/wiki/IP_address_spoofing
This could be achieved using RAW sockets or WinPCap using SharpPCap to interop to WinPCap
http://www.tamirgal.com/blog/page/SharpPcap.aspx
Your machine IP address is simply the IP address given to your machine to be used internally by devices within your home network. This is how routers, switches and other client devices can deliver and exchange packets.
You cannot spoof your external-facing IP in this manner. Using proxies will make the proxy's IP appear to be your external-facing IP.
I do not suggest changing your internal IP unless you know what you are doing and actually have a need for it to be static. For example, I forward ports on my router so I can run services. The router knows to point that traffic directly to my internal IP. Because DHCP can change your IP (due to lease expiration and what not), it's best that I make my internal IP static.
Also, depending on your network configuration, your internal IP has a certain format, like 192.168.1.X.
The best way to http://www.change-ip-proxy.com>change your ip address is through a proxy. In my search for a proxy, I found that having a reliable company behind the proxy is very important. Everything you do is sent through the company’s proxy, so you want to be sure that you can trust them to not read or steal your personal information. Or else there's no point in having a proxy.