Method of digital information for penetrating NAT/FW and the system

Abstract

A method and system for digital information penetration through NAT / FW related to telecommunication technology. An internal client communicates with a verification server system on the public network through its own port for monitoring data flow, and obtains the information of the internal client monitoring data flow. The external network address and port number corresponding to the internal network address and port number, and notify the content server system; the content server system transmits the external network address and port number according to the obtained external network address and port number Data flow, the internal network address and port number are mapped out by NAT / FW, so that the data flow is transparently transmitted to the internal client. The present invention solves the contradiction between data exchange and network security in the prior art, making it unnecessary to modify Under the condition of NAT / FW configuration, digital information can pass through NAT / FW.

Description

Technical field [0001] The present invention relates to electrical communication technology, in particular to a method and system for NAT / FW penetration of digital information. Background technique [0002] Network Address Translation NAT, or Network Address Translation, is a standard method used to map an address domain (such as a private Intranet) to another address domain (such as the Internet). NAT allows hosts in an organization's private intranet to transparently connect to the public The host in the domain does not need the internal host to have a registered public IP address. All internal network data packets going out through NAT will be translated at the NAT, usually the source IP address / port of these packets is converted to the outside of the NAT At the same time, NAT adds a record in its mapping table so that when the response packet of this packet comes back, it can determine which host on the internal network to send. The packet whose source address / port is changed...

AI Technical Summary

Problems solved by technology

This creates a dilemma: in order to establish a data connection, the client must always monitor incoming calls, while NAT / FW usually prevents any unsolicited data packets from passing through, even if the network administrator opens a firewall / NAT. port to receive call setup data packets, for example, the default port of H.323 call signaling is port 1720, and the default port of SIP call is port 5060, but the IP voice / video communication protocol also requires many other ports to be opened to receive call control information. Establish voice and video channels, these port numbers are allocated dynamically, which means that network managers will have to open all ports on the firewall in order to allow voice / video communication, so that NAT / FW will lose its meaning of existence, For reasons of network security, few network managers allow their network NAT / FW to be so open

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