MoCA Network Key Derivation Using Random Salt

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

MoCA networks face security vulnerabilities due to weak static keys derived from user-entered passwords, which can be compromised in brute-force or dictionary attacks, despite using the Advanced Encryption Standard (AES) for link privacy.

Innovation Solution

Generating a random Salt (SALT) by the Network Coordinator (NC) and combining it with the user's password to create stronger static keys, using processes like RFC 2898/PKCS #5, to derive dynamic keys for enhanced network security without increasing password length.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If static keys are derived from user-entered passwords using AES, then link privacy is enabled, but the keys are vulnerable to brute-force and dictionary attacks

Engineering Contradiction:

Improvelink privacyVSAvoidvulnerability to attacks

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies preliminary action by pre-generating a random SALT value that is distributed to all network nodes before the actual key derivation process. This SALT is combined with the user password during static key generation, creating a stronger derived key that is resistant to brute-force and dictionary attacks. The SALT is established in advance as part of the network setup, enabling secure key derivation without requiring users to remember longer or more complex passwords.

Inventive Principle:

Principle #10Preliminary action

2Strength

If password length is increased to strengthen keys, then key strength improves, but password management complexity increases

Engineering Contradiction:

Improvekey strengthVSAvoidpassword management

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The patent introduces an intermediary element - a random SALT value - that mediates between the user password and the final static key. Instead of requiring users to provide longer or more complex passwords directly, the SALT acts as an intermediate component that is combined with the password through a key derivation function. This intermediary SALT, which is managed by the network coordinator and distributed to nodes, provides the additional entropy needed for stronger keys without increasing the burden on users.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS10594672B2Secure node admission in a communication network

Publication Date: 2020.03.17 ENTROPIC COMM INC

AI summary

System and methods are provided for admission to networks that include at least one node providing network coordinator functions. A network coordinator may have a random number generator, with the network coordinator distributing a random number within a network that include at least a first node and a second node. The network coordinator may receive a request for a dynamic encryption key from the first node, with the request being encrypted using a static encryption key unique to the first node, and with the static encryption key being determined based on the distributed random number. The network coordinator may then send a dynamic encryption key to the first node, with the dynamic encryption key being encrypted using the static encryption key. The second node may then admit the first node into the network. The network may be a Multimedia over Coax Alliance (MoCA®) network.