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Yes they all support punching holes, in fact, I’m punching holes right now, otherwise I won’t be able to reply. But if you don’t punch, then there’s no hole. Y

Yes they all support punching holes, in fact, I’m punching holes right now, otherwise I won’t be able to reply. But if you don’t punch, then there’s no hole. Your TCP stack is unlikely to accidentally punch port 3398 when you’re browsing hn.

dfawcus 2y ago
The nature of an EIM/EIF NAT is that the hole exists without punching, as soon as the device behind the NAT connects to anywhere public. That action creates a public side mapping on the NAT, being Proto/IP/Port - Proto generally being TCP or UDP. While that mapping exists, any packet within that protocol, from any source address or port in the whole IPv4 Internet can be directed at that mapping, and received by the client computer. Generally TCP syn's will be dropped by the client (unless they explicitly opened a fixed mapping, and are hence running a TCP server), but any UDP packet for an open UDP mapping will be received. AFAIK, the various gaming programs tend to run over UDP... The punching per-se is to coordinate between two clients, each behind NATs, and/or each behind actual firewalls (as opposed to the NAT filtering function).
throw0101a 2y ago
> Yes they all support punching holes, in fact, I’m punching holes right now, otherwise I won’t be able to reply. But if you don’t punch, then there’s no hole. That is not what is meant by "hole punching": > Networked devices with public or globally accessible IP addresses can create connections between one another easily. Clients with private addresses may also easily connect to public servers, as long as the client behind a router or firewall initiates the connection. However, hole punching (or some other form of NAT traversal) is required to establish a direct connection between two clients that both reside behind different firewalls or routers that use network address translation (NAT). * https://en.wikipedia.org/wiki/Hole_punching_(networking) https://en.wikipedia.org/wiki/Hole_punching_(networking) * https://en.wikipedia.org/wiki/Port_Control_Protocol https://en.wikipedia.org/wiki/Port_Control_Protocol * https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protocol https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protoc...

dfawcus 2y ago

The nature of an EIM/EIF NAT is that the hole exists without punching, as soon as the device behind the NAT connects to anywhere public. That action creates a public side mapping on the NAT, being Proto/IP/Port - Proto generally being TCP or UDP. While that mapping exists, any packet within that protocol, from any source address or port in the whole IPv4 Internet can be directed at that mapping, and received by the client computer. Generally TCP syn's will be dropped by the client (unless they explicitly opened a fixed mapping, and are hence running a TCP server), but any UDP packet for an open UDP mapping will be received. AFAIK, the various gaming programs tend to run over UDP... The punching per-se is to coordinate between two clients, each behind NATs, and/or each behind actual firewalls (as opposed to the NAT filtering function).

throw0101a 2y ago

> Yes they all support punching holes, in fact, I’m punching holes right now, otherwise I won’t be able to reply. But if you don’t punch, then there’s no hole. That is not what is meant by "hole punching": > Networked devices with public or globally accessible IP addresses can create connections between one another easily. Clients with private addresses may also easily connect to public servers, as long as the client behind a router or firewall initiates the connection. However, hole punching (or some other form of NAT traversal) is required to establish a direct connection between two clients that both reside behind different firewalls or routers that use network address translation (NAT). * https://en.wikipedia.org/wiki/Hole_punching_(networking) https://en.wikipedia.org/wiki/Hole_punching_(networking) * https://en.wikipedia.org/wiki/Port_Control_Protocol https://en.wikipedia.org/wiki/Port_Control_Protocol * https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protocol https://en.wikipedia.org/wiki/Internet_Gateway_Device_Protoc...