MAC address vendor

SERNET (SUZHOU) TECHNOLOGIES CORPORATION — D8:21:DA (MA-L) + 12 MA-M blocks

Primary prefix
D8:21:DA
Block
MA-L
Status
Active

Summary

// what this is
Sernet is registered to MAC prefix D8:21:DA and 12 more in the IEEE OUI database. When a device's MAC address begins with D8:21:DA, that block was registered by Sernet — the OUI identifies the maker of the network hardware, which is not always the brand on the device.
// analyst note
Only D8:21:DA is confirmed in the local MA-L cache; broader ~15-prefix MA-L footprint claimed by third-party sites is Likely. Devices are OEM/ODM SOHO/consumer gear shipped under partner brands, so an in-the-wild MAC with these prefixes typically surfaces under a partner brand (e.g. NETGEAR/ARRIS), not the SERNET name.
[ 01 ] — Context

About this vendor.

Updated  ·  Confidence: Medium

The vendor-sernet slug resolves to SERNET (SUZHOU) TECHNOLOGIES CORPORATION, a Chinese OEM/ODM hardware manufacturer based in Suzhou Industrial Park, Jiangsu Province. In the local IEEE registry caches the organization holds one MA-L (24-bit) assignment, D8:21:DA, plus twelve MA-M (28-bit) blocks recorded in the IEEE MA-M registry; no MA-S (36-bit) assignment was found. Third-party MAC lookup sites attribute a larger MA-L footprint to the same registered name, but only D8:21:DA is confirmed in the local MA-L cache, so the broader count is treated as Likely rather than Confirmed. Trade records describe the company as a contract manufacturer of consumer and SOHO networking gear — wireless routers, modem-routers, USB Wi-Fi adapters, VoIP gateways, IP cameras, and NAS units — supplied under OEM contracts to brands including NETGEAR and ARRIS. The single most important caveat is disambiguation: this entity is entirely distinct from SerNet GmbH (sernet.de, Göttingen, Germany), an information-security software and managed-services firm that holds no MAC OUI registrations. The lone CVE found under the bare vendor string "sernet" (CVE-2021-36981, in the verinice governance software) belongs to the German company, not this OUI holder, and must not be attributed to SERNET Suzhou hardware. As with every OUI entry, IEEE publishes no registration date for these blocks; any "date registered" shown on third-party lookup tools is a database artifact, not an IEEE fact, and no date is recorded here.

IEEE assignment (MA-L)
D8:21:DA → SERNET (SUZHOU) TECHNOLOGIES CORPORATION [Confirmed] — local the IEEE MA-L registry (line 388)
IEEE assignments (MA-M, 28-bit)
C4:A5:59:E, 88:3C:C5:9, 38:1F:26:1, 50:A0:30:D, D0:96:86:0, 8C:51:09:A, 48:5E:0E:6, 04:C9:8B:0, B4:4D:43:7, 58:48:49:4, 8C:55:70:B, 7C:83:34:9 (12 blocks) [Confirmed] — local the IEEE MA-M registry
MA-S (36-bit)
none found [Confirmed] — local the IEEE MA-S registry
Registry / block sizes
one MA-L (24-bit OUI) plus twelve MA-M (28-bit) blocks [Confirmed] — local registry CSVs. NOTE: IEEE public OUI data publishes NO assignment/registration date; any "date registered" on third-party tools is a database artifact, not an IEEE fact.
Broader MA-L footprint
third-party lookup sites list ~15 MA-L prefixes (e.g. C0:9F:51, 04:71:53, 98:2C:C6, 7C:13:1D, D0:B6:6F, 74:06:35, 58:76:AC, F4:23:9C, E0:E8:05, A0:95:7F, 48:3E:5E, C4:0F:A6, 78:B3:9F, 0C:67:14) for the same registered name, but only D8:21:DA is confirmed in the local MA-L cache
[Likely] — maclookup.app/vendors/sernet-suzhou-technologies-corporation, udger.com
HQ / country
No. 8 Tangzhuang Road, Suzhou Industrial Park, Suzhou City, Jiangsu Province, China 215021; country CN [Confirmed] — local the IEEE MA-M registry (address consistent across all MA-M rows); corroborated by maclookup.app
Company status
active manufacturing/export entity (no public consumer-facing brand site located) [Likely] — panjiva.com/Sernet-Suzhou-Technologies-Corp/1280416
Device types
OEM/ODM consumer and SOHO networking hardware — wireless routers, modem-routers, USB Wi-Fi adapters, VoIP gateways, IP cameras (wired and Wi-Fi), NAS/network storage, ADSL routers, access points [Confirmed] — matchory.com/supplier/sernet-suzhou-technologies, panjiva.com
OEM customers
NETGEAR and ARRIS appear in trade records as receiving parties; Extreme Networks also appears [Likely] — panjiva.com, matchory.com (trade-record inference, single class of source)
Vendor website
none confirmed for this entity; trade data references www.sercomm.com, which is Sercomm Corporation (a distinct Taiwanese ODM), not this company [Likely] — panjiva.com
Security context
no CVEs or advisories attributed to SERNET Suzhou hardware in this research pass; the device categories it builds (IP cameras, SOHO routers, NAS) are a historically high-CVE segment, but no firmware CVE traced to SERNET Suzhou branding was found [Likely] — cve.report/vendor/sernet, nvd.nist.gov
Disambiguation (critical)
SerNet GmbH (sernet.de, Göttingen, Germany) is a separate information-security software/VAR firm with NO MAC OUI registrations; CVE-2021-36981 (verinice, insecure Java deserialization) belongs to SerNet GmbH, NOT this OUI holder [Confirmed] — sernet.de/en, cve.report/vendor/sernet
Allocated date
Unknown — IEEE publishes no registration dates for MAC/OUI assignments; third-party per-prefix "date registered" values are database artifacts [Confirmed] — IEEE OUI data schema (Registry, Assignment, Organization Name, Organization Address only)
[ 02 ] — OUI prefixes

Assignments by IEEE.

1 of 13
// registered prefixes1 of 13
  1. D8:21:DAMA-L
Listing 1 representative prefixes; this vendor holds 13 total assignments.
[ 03 ] — Related

Keep digging.