What do think of SLDP. Layer-2 discovery for IPv4/IPv6

I built SLDP (Simple Layer-2 Discovery Protocol) to solve the manual MAC-to-IP mapping nightmare when integrating IPv6-only devices into legacy IPv4 networks (industrial IoT, substations, etc.).

How it works:

· Operates directly over Ethernet frames (EtherType 0x88B5).
· Requires zero IP stack initialization (no IP, DHCP, DNS, or sockets).
· Stateless broadcast/unicast handshake.
· Runs on-demand during commissioning, then goes silent in production.

What it is NOT:
It's not a replacement for ARP/NDP/LLDP, and not a runtime protocol. Just a targeted bootstrapping tool.

I've written a C implementation for Linux, a security blueprint (CLL Trust Oracle), and included a Wireshark dissector in the repo so you can easily inspect the frames.

The Ask: I'm looking for feedback from network engineers. Does this solve a real problem for you? Are there glaring architectural flaws?

Repo: https://github.com/cyberghost-2/Simple-L2-Discovery-protocol-SLDP-

Bug reports and critiques are very welcome. Thanks.

Impact

SLDP itself is a protocol proposal and implementation intended to simplify network commissioning in mixed IPv4/IPv6 environments. There is no indication of inherent vulnerabilities or exploitation in the provided information. The impact is primarily operational, potentially reducing manual configuration errors and improving integration efficiency. No security incidents or exploit code are known. The security blueprint aims to mitigate spoofing risks during commissioning.

Defensive guidance

No remediation or patch is applicable as SLDP is a newly introduced protocol and tool without reported vulnerabilities. Users should review the security blueprint (CLL Trust Oracle) included in the implementation to ensure appropriate protections against spoofing during commissioning. Since SLDP is designed to run only on demand and not in production, limiting its use to commissioning phases reduces exposure. Network engineers should evaluate the protocol carefully before deployment and monitor for any future advisories.

Summary

SLDP is a specialized Layer-2 discovery protocol designed to bridge IPv4-only and IPv6-only devices by performing an on-demand handshake over Ethernet frames (EtherType 0x88B5) without requiring IP stack initialization. It addresses operational challenges in hybrid network environments by automating MAC-to-IP mapping during commissioning phases. The protocol exchanges a broadcast DISCOVERY_REQ followed by a unicast DISCOVERY_RESP containing session and address information encoded uniformly. SLDP is explicitly not a runtime protocol and does not replace existing address resolution protocols. It includes a security design based on the CLL Trust Oracle to mitigate spoofing risks during discovery. The implementation is open source with a Wireshark dissector for traffic analysis. No vulnerabilities or active exploits are reported.

What do think of SLDP. Layer-2 discovery for IPv4/IPv6

Discussion

Links cited in the discussion

Impact

Defensive guidance

Summary

References

Community reviews

Discussion

Links cited in the discussion

AI analysisMachine-generated, updated 17 Sep 2026, 14:17 UTC

Technical details

References

Community reviews

Related threats