Could be the NAT on your router or his/her router. try disabling or opening the NAT.
Depends on the type of router you have. Google "How to open NAT setting on a [Enter router type here]". You should find your answer there.
It depends on your router. You can find the answer on your router manufacturer's website.
You need to access the settings on your router.
A router passes traffic between networks to reach other computers or servers. A router also does NAT. Nat masquerades traffic behind the router with private IP(Non-internet route able) with the Public IP (Internet route able)
you don't
you need a router to fix it sorrymarian4
65536 virtual ports. Port number is a 16 bit number, so there are 2^16 (65536) ports for a NAT router.
debug ip nat
You have to change your NAT type through your router. Call your internet provider for instructions
A router can improve network security if it includes the use of NAT (network address translation) and/or a firewall.
Configure your router with a DMZ (demilitarized zone). This sets one of the computers as the computer that all traffic goes to if it isn't on the NAT. You will need to have some type of hardware or software firewall running on this computer, since it will be exposed to the internet without the protection that a router provides. How you do this depends on what router you have. Look up DMZs in your router's manual, or call tech support.