The slug resolves to "Siemens Industrial Automation Products Ltd., Chengdu," a Siemens factory-automation subsidiary (the Siemens Electronics Works Chengdu, SEWC) at Tianyuan Road 99, High Tech Zone West, Chengdu, Sichuan 611731, China. The IEEE registry lists four MA-L (24-bit OUI) blocks under this exact org name — E0:DC:A0, 10:D6:57, 4C:E7:05, and 8C:F3:19 — each spanning ~16.7 million addresses. This is a distinct registrant from Siemens AG's much larger German OUI footprint, so consolidating these four Chengdu blocks into one vendor entry is more useful than minting four near-identical per-prefix pages. The hardware behind these allocations is SIMATIC-family industrial automation gear: programmable logic controllers (the S7-1200 and S7-1500 lines), human-machine interfaces, and industrial PCs, built at the Chengdu plant for both the Chinese and global markets. These devices speak PROFINET — Siemens' industrial Ethernet standard — and the broader SIMATIC ecosystem (ET 200 distributed I/O, SCALANCE switches) sits on the same networks. The practical signal for a network analyst: one of these OUIs on a network is a strong indicator of an operational-technology / industrial control system (ICS) environment rather than office IT, which carries a specific security posture. Siemens PROFINET and S7 devices have a well-documented ICS vulnerability history (multiple CISA advisories), and S7 PLCs are a recurring internet-exposure and reconnaissance target. The standard OUI caveat applies on both ends: a globally-administered Siemens OUI identifies genuine Chengdu-built hardware, but its absence does not prove "not Siemens," and OUI alone is not a basis for inventory or access control. IEEE publishes no registration date for any of these blocks, so no date is asserted here.
- IEEE assignment
- 4 prefixes → Siemens Industrial Automation Products Ltd., Chengdu, registered Chengdu, Sichuan, CN [Confirmed] — IEEE OUI registry (local oui.csv, rows 341 / 7333 / 8268 / 16909)
- Registry / block size
- MA-L (24-bit OUI) for all four; ~16.7M addresses each [Confirmed] — IEEE oui.csv. NOTE: IEEE's public OUI data publishes NO assignment/registration date (oui.csv columns are only Registry, Assignment, Organization Name, Organization Address); any "date registered" on third-party tools is a database artifact, not an IEEE fact.
- HQ / country
- Tianyuan Road 99 (No.99), High Tech Zone West, Chengdu, Sichuan 611731, CN (China) [Confirmed] — IEEE oui.csv; corroborated siemens.com China operating-companies page
- Company status
- active Siemens subsidiary (Siemens Electronics Works Chengdu / SEWC), factory-automation focus [Confirmed] — siemens.com/en-us/company/operating-companies-china/, automationinside.com
- Verified prefixes (all MA-L)
- E0:DC:A0, 10:D6:57, 4C:E7:05, 8C:F3:19 [Confirmed registry; E0:DC:A0 and 4C:E7:05 additionally corroborated by public MAC-lookup tools] — IEEE oui.csv; cleancss.com, macvendorlookup.com, hwaddress.com
- Device types
- SIMATIC PLCs (S7-1200 / S7-1500), HMIs, industrial PCs (IPCs); part of the PROFINET / ET 200 / SCALANCE ecosystem [Confirmed] — siemens.com SIMATIC pages, manufacturing.net (Chengdu digital factory)
- Primary protocol
- PROFINET (industrial Ethernet); S7 / ISO-TSAP on TCP/102 [Confirmed] — siemens.com/products/profinet/, Forescout research
- Registration date
- none published — IEEE publishes no OUI registration dates; third-party "date registered" values are database artifacts, not IEEE facts [Confirmed null] — en.wikipedia.org/wiki/Organizationally_unique_identifier
- IANA reference
- not applicable — OUI assignments are administered by the IEEE Registration Authority, not IANA; no RFC reference applies [Confirmed null] — en.wikipedia.org/wiki/Organizationally_unique_identifier
- MA-M / MA-S (OUI-36) entries
- none found under this exact org name [Confirmed] — IEEE mam.csv, oui36.csv (local)
- Related registrant
- Siemens AG (separate, much larger German OUI footprint — distinct legal entity from this Chengdu registrant)
- Security context
- Siemens PROFINET / SIMATIC devices carry a documented ICS/OT vulnerability profile, e.g. CVE-2019-13946 and CVE-2019-10936 (PROFINET resource-exhaustion DoS, CISA ICSA-19-283-02), CVE-2017-2680/2681 & CVE-2018-4843 (crafted PROFINET DCP packets → DoS on the local L2 segment, CISA ICSA-17-129-01/02 & ICSA-18-079-02), and CVE-2022-38465 (global private-key extraction on S7-1500 → firmware-install/takeover). Many DCP vectors require attacker presence on the same Ethernet segment; internet-exposed S7 on TCP/102 is the higher-risk surface (~6,500 S7 PLCs Shodan-visible as of Jan 2024). [Confirmed] — cisa.gov ICS advisories, forescout.com, entro.security
- Analyst note
- One of these OUIs on a network strongly indicates an ICS/OT environment (factory automation, process control, critical infrastructure). OUI-based SIMATIC fingerprinting is a documented ICS-recon step (Nmap s7-info.nse). A globally-administered Siemens OUI = genuine hardware; absence ≠ "not Siemens"; don't rely on OUI alone for inventory or MAC-based access control.