David & Akash, this configuration should not be necessary on a properly configured NAT device. NAT inherently handles this type of translation so packets sent out are encapsulated and viewed by the destination as from a single source IP but when the packets are returned the NAT device removes the encapsulation and sends the packets to the correct internal address. What you have listed below is known as PAT (port address translation) and would be used primarily to direct ALL inbound traffic to a certain port. For example if you had a web browser at internal IP 10.0.0.5 you could add a static PAT entry on your NAT device that routes all inbound port 80 traffic to IP 10.0.0.5. For video games and other applications that actually initiate the session to the remote server the NAT device itself is capable of handling the routing of packets to the correct host. This avoids you having to configure your game to run on a single port also.
I personally do this at home with a game called Everquest and am able to run multiple sessions of the game from a single real world IP. Any of my four PC's can run the game from their internal non-routable IP, through the NAT device. Friends do the same for games such as Quake, Unreal, DAoC and many others with no problem. If you have a complicated network setup that does policy routing for TCP & UDP through different types of connections you may have some problems with various video games and applications. The only case of this I have seen is a friend who had a DSL line what handled all TCP traffic and a Cable Modem connection where all UDP traffic was routed. When a game using both protocols would try to reach the host it would fail because it would have multiple IP's listed for the host. This type of configuration is very rare in a home user network, but worth mentioning. Tim -----Original Message----- From: David Rowe [mailto:[EMAIL PROTECTED]] Sent: Friday, September 13, 2002 4:26 PM To: 'Akash Malhotra'; [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: RE: NAT Help I just set this up for a friend who wanted to play Warcraft3. Configure NAT to route to each internal IP via ports. Each game has a setting where you type in a port. webgame | | NAT | ------------ | | 10.0.0.1 10.0.0.2 user1 user2 port 6112 port 6113 set NAT to route packets with port 6112 to 10.0.0.1 set NAT to route packets with port 6113 to 10.0.0.2 -----Original Message----- From: Akash Malhotra [mailto:[EMAIL PROTECTED]] Sent: Friday, September 13, 2002 8:10 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: NAT Help Hi I just want to know how NAT wokrs in general.Any help is appreciated. The reason me asking help abt NAT is i want to know how NAt will behave when two users are behind NAT is contatcting same applictaion.For Eg If two users want to play multiuser game and both of them are behind NAT than how NAT is gonna know who is what??? and how is NAT gonna response to different packet. situation can be described below Website -> Game Application | (Multi User Game) | NAT | ------ | | user1 user2 ( both are playing with each other) ANy suggestion on this issue ?? I Want to know the behaviour of NAT -Akash ------------------------------------------------------------------------ ---- --_ Akash Malhotra MEnet EMAIL: PHONE: [EMAIL PROTECTED] Off: (612)626-9800 [EMAIL PROTECTED] Apt: (612)623-9193
