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Vlad Avramut
Vlad Avramut

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Understanding Encryption in LoRa & Meshtastic Networks

This is an excerpt.

Read the full technical analysis:
https://www.vladavramut.com/articles/lora-meshtastic-encryption.html


Encryption is often cited as a key strength of LoRa and Meshtastic networks — but understanding what encryption protects and what it does not is crucial for real-world deployments.

Too many guides treat encryption as a silver bullet. In reality, it is a necessary security layer, not an all-encompassing guarantee of confidentiality, integrity, or network resilience.

This excerpt breaks down how encryption functions in LoRa and Meshtastic and what engineers need to know before relying on it.


What Encryption Does in LoRa & Meshtastic

LoRa radios operate over unlicensed sub-GHz bands. The base physical layer does not include encryption by default. Encryption is added at higher layers:

• LoRaWAN uses AES-128 at the network and application layers

• Meshtastic uses application-level AES encryption of message payloads

This protects message content from casual over-the-air eavesdropping — but it does not hide metadata such as:

• packet timing

• frame size

• number of hops

• source/destination identifiers

Metadata can still reveal network behavior in traffic analysis attacks.


Encryption vs. Traffic Analysis

If an attacker can observe the channel, even encrypted traffic yields observable signals:

• packet bursts

• inter-packet intervals

• relay patterns

• hop counts

These signals can be used to infer:

• node density

• high-traffic nodes

• potential backbone nodes

• likely geographic clustering

Encryption does not prevent this metadata leakage — only payload confidentiality.


Key Management Is the Critical Weak Spot

Encryption is only as strong as its key handling.

In many Meshtastic deployments:

• keys are pre-shared

• key distribution is ad hoc

• key rotation is manual or nonexistent

A compromised node with access to shared keys can:

• decrypt payloads

• impersonate nodes

• inject malicious traffic

• disrupt routing topologies

Proper key management requires systemic planning, not default settings.


Encryption Alone Does Not Provide Integrity

Meshtastic and LoRa encryption protect payload secrecy, but they do not inherently:

• authenticate source identity

• validate routing behavior

• guard against replay attacks

• resist selective jamming

Real systems must consider these attack vectors at the protocol and topology levels.


Continue reading the full technical analysis:
https://www.vladavramut.com/articles/lora-meshtastic-encryption.html

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