The OUI prefix E4:29:3D is registered to Shenzhen Sy-Fiber Optical Communication Technology Co., Ltd., a Guangdong-based manufacturer of fiber-to-the-home (FTTH/FTTx) access gear. The block is a standard 24-bit MA-L (MAC Address Block Large) assignment carrying the registry address 11/F, Manjinghua Yingshuo Commercial Building, Songgang Street, Baoan District, Shenzhen. The company markets a full PON access portfolio: GPON/EPON/XPON OLTs on the ISP side, ONUs/ONTs and Wi-Fi 6 routers as customer-premises equipment, plus switches, SFP transceivers, PLC splitters, and ODF enclosures. In practice a device carrying this OUI is almost always a consumer- or ISP-grade fiber endpoint deployed in a fiber-to-the-home network rather than enterprise infrastructure. No SY-Fiber-specific CVEs were found, but the device class — GPON ONUs/OLTs and FTTH routers — is a well-documented risk category: default credentials, WAN-side management exposure, and Mirai-style botnet recruitment are recurring problems across GPON CPE vendors broadly (e.g. CVE-2018-10561/10562 on DASAN GPON, CVE-2020-8958 on V-SOL ONUs). Treat E4:29:3D hardware as a generic GPON CPE risk profile until device-specific research surfaces. As with all OUI data, IEEE publishes no assignment date; any "date registered" on third-party lookup tools (e.g. the 2021-07-21 seen on maclookup.app) is a database artifact, not an IEEE fact, and is not recorded here.
- IEEE assignment
- E4:29:3D → Shenzhen Sy-Fiber Optical Communication Technology.Co.,Ltd [Confirmed] — IEEE MA-L (enrichment/registries/oui.csv, line 843); cross-confirmed via maclookup.app API (https://api.maclookup.app/v2/macs/E4293D)
- Registry / block size
- MA-L (24-bit OUI, ~16.7M addresses) [Confirmed] — IEEE oui.csv; not present in mam.csv (MA-M) or oui36.csv (MA-S)
- HQ / country
- 11/F, Manjinghua Yingshuo Commercial Building, Songgang Street, Baoan District, Shenzhen City, Guangdong Province, CN 518105 [Confirmed] — IEEE MA-L (oui.csv). NOTE: raw registry data contains a typo ("Provicne"); normalized to "Province" here.
- Country
- CN (China) [Confirmed] — IEEE oui.csv; corroborated by maclookup.app and LinkedIn
- Assignment date
- not published — IEEE publishes NO assignment/registration date for OUI/MA-L blocks. A "2021-07-21" appears on third-party tools but is a database artifact, not an IEEE fact; not recorded. [Unknown] — maclookup.app (artifact only)
- Company status / website
- http://www.sy-fiber.com/ is the company's official site (serves a self-signed certificate; content not fully fetchable) [Likely] — LinkedIn company profile
- Device types
- FTTH/FTTx access equipment — GPON/EPON/XPON OLTs, ONUs/ONTs, Wi-Fi 6/AX3000 routers, switches, SFP transceivers, fiber optic cables, PLC splitters, ODF enclosures [Confirmed] — LinkedIn, sy-fiber.com
- Industry segment
- telecommunications — passive optical network (PON) access equipment; ISP-side OLT hardware and CPE [Confirmed] — LinkedIn company profile
- Company size
- 51–200 employees (self-reported) [Likely] — LinkedIn company profile (single-source, self-reported)
- Security context
- no SY-Fiber-specific CVEs found. Device class (GPON ONU/OLT, FTTH routers) carries class-wide risks — default credentials, WAN-side management exposure, Mirai-style botnet recruitment; documented broadly across GPON CPE (CVE-2018-10561/10562 DASAN, CVE-2020-8958 V-SOL). No evidence these specific CVEs apply to SY-Fiber hardware; treat as generic GPON CPE risk profile. [Likely] — pierrekim.github.io GPON FTTH analysis, threatdown.com, vsolcn.com
- Analyst note
- a device with this OUI on a globally-administered address is genuine SY-Fiber hardware, almost certainly a fiber endpoint (ONU/ONT/OLT/FTTH router). OUI alone does not indicate firmware version or patch state — combine with device fingerprinting for any access-control decision.