NAT Bypass via SMS IP Exchange

Solution Overview

Problem

Devices behind NAT routers cannot act as servers accessible from the WAN due to limitations in port forwarding configurations, which require public IP addresses and may pose security risks, and cloud-based services are costly and not suitable for secure communications.

Innovation Solution

A method involving SMS messaging to transmit IP addresses between devices, allowing a client to access a service provided by a host connected to a WAN through a NAT router by determining the host's IP address and establishing a dynamic route for communication, bypassing traditional port forwarding requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If port forwarding is configured to allow devices behind NAT routers to act as servers, then accessibility from WAN is improved, but security risks increase and public IP addresses are required

Engineering Contradiction:

ImproveaccessibilityVSAvoidsecurity risks

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent introduces a cloud-based intermediary service that mediates communication between devices behind NAT routers and external clients. Instead of directly exposing devices through port forwarding, the cloud service acts as a mediator that receives client requests, establishes connections to the target devices, and forwards communications bidirectionally, thereby maintaining security while enabling accessibility

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent inverts the traditional client-server model by allowing devices behind NAT routers to initiate outbound connections to cloud servers, which then enable inbound communication. Instead of opening ports to allow external connections in (traditional port forwarding), the system establishes outbound connections that are then used to enable inbound traffic, effectively reversing the direction of the initial connection establishment

Inventive Principle:

Principle #13The other way round (Inversion)

2Ease of operation

If cloud-based services are used to enable communication behind NAT, then accessibility is improved, but cost increases

Engineering Contradiction:

ImproveaccessibilityVSAvoidcost

Core Design Contradiction:

Ease of operationVSLoss of energy

Solution Approach 1:

The patent implements a self-service mechanism where devices behind NAT routers autonomously establish outbound connections to cloud servers and register their presence. The system uses existing communication protocols (SMS, email, or IP-based communication) that devices already possess, eliminating the need for paid cloud service subscriptions while maintaining accessibility functionality

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent creates a universal communication mechanism that can operate across multiple platforms and networks using existing infrastructure (SMS gates, email servers, or direct IP communication). This multi-functional approach allows the system to adapt to different network environments and avoid proprietary cloud service fees by utilizing freely available communication channels

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Productivity

If traditional port forwarding is used, then direct communication is enabled, but it requires public IP addresses and port configuration complexity

Engineering Contradiction:

Improvecommunication efficiencyVSAvoidconfiguration complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent introduces a cloud-based intermediary service that mediates communication between devices behind NAT routers and external clients. Instead of directly exposing devices through port forwarding, the cloud service acts as a mediator that receives client requests, establishes connections to the target devices, and forwards communications bidirectionally, thereby maintaining security while enabling accessibility

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent inverts the traditional client-server model by allowing devices behind NAT routers to initiate outbound connections to cloud servers, which then enable inbound communication. Instead of opening ports to allow external connections in (traditional port forwarding), the system establishes outbound connections that are then used to enable inbound traffic, effectively reversing the direction of the initial connection establishment

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS10805260B2Method for transmitting at least one IP data packet, related system and computer program product

Publication Date: 2020.10.13 STMICROELECTRONICS SRL

AI summary

A method for transmitting an Internet Protocol (IP) data packet from a first device to a second device, includes: transmitting a message from the first device to a telephone number associated with the second device; receiving the message at the second device and, in response to the message, determining a first IP address of the first device and transmitting a first IP packet from the second device to the first IP address; receiving the first IP packet at the first device and determining a source IP address of the first IP packet; and transmitting a second IP packet from the first device to the source IP address of the first IP packet.