Interphone Service is a Polish electronics contract manufacturer (EMS) based in Mielec, in the EURO-PARK MIELEC Special Economic Zone, holding the IEEE MA-L block FC:58:DF registered to "Interphone Service" at Inwestorow 8, Mielec 39-300, Poland. Founded in 2009, the company became a wholly-owned subsidiary of Cyfrowy Polsat S.A. (the Polsat Plus Group) in April 2015, when Cyfrowy Polsat acquired it for PLN 35 million and made it the group's primary in-house set-top box manufacturing facility. Devices bearing this OUI are predominantly satellite TV decoders (set-top boxes) and GSM/home-internet modems distributed to Polsat Box / Polsat Plus pay-TV subscribers across Poland, alongside the company's broader contract electronics manufacturing for telecommunications and consumer-electronics clients. In practical terms, an FC:58:DF address on a network most likely identifies a Polsat Box satellite decoder or a home-internet modem owned by a Polish subscriber. No public CVEs or vendor-specific security advisories were found for Interphone Service hardware; the risk profile is consistent with the consumer STB/modem class, where devices receive operator-managed IPTV/content streams and attach to home networks. Note that a separate MA-S entry exists for the unrelated "TOKYO INTERPHONE CO.,LTD." — a different organization that does not belong to this vendor entry.
- IEEE assignment
- FC:58:DF → "Interphone Service", registered Mielec, Poland [Confirmed] — IEEE MA-L (enrichment/registries/oui.csv)
- Registry / block size
- MA-L (24-bit OUI; ~16.7M addresses) [Confirmed] — maclookup.app, uic.io. NOTE: IEEE publishes NO assignment/registration date for OUI blocks; the "2021-04-17" date shown on maclookup.app and uic.io is a third-party database artifact, not an IEEE fact, and must not be presented as an IEEE registration date.
- Registered address / country
- Inwestorow 8, Mielec 39-300, Poland (PL) [Confirmed] — IEEE MA-L, maclookup.app
- Full legal name
- Interphone Service Sp. z o.o. [Confirmed] — interphone.com.pl, maclookup.app, uic.io
- Company status
- active [Confirmed] — interphone.com.pl
- Company founded
- 2009 (April 30, 2009); operating in EURO-PARK MIELEC Special Economic Zone since 2010 [Confirmed] — LinkedIn company page, grupapolsatplus.pl
- Parent company
- Cyfrowy Polsat S.A. (Polsat Plus Group); acquired April 2015 for PLN 35 million; serves as Cyfrowy Polsat's in-house set-top box manufacturing facility [Confirmed] — grupapolsatplus.pl press release
- Device types
- satellite TV set-top boxes (decoders) and GSM/home-internet modems, primarily for Cyfrowy Polsat (Polsat Box / Polsat Plus); also general contract electronics manufacturing (EMS) [Confirmed] — grupapolsatplus.pl, LinkedIn, ep.com.pl
- Certifications
- ISO 9001:2015 (quality) and ISO 14001:2015 (environmental) [Confirmed] — aleo.com company listing
- Website
- https://www.interphone.com.pl/en/ [Confirmed] — interphone.com.pl
- Related / not-to-confuse
- a separate MA-S block (8C:1F:64:65:2x) is registered to the unrelated "TOKYO INTERPHONE CO.,LTD." — different org, not this vendor [Confirmed] — IEEE MA-S (oui36.csv)
- Security note
- consumer-facing STBs/broadband modems in subscriber homes; operator-managed (Cyfrowy Polsat); no public CVEs or vendor-specific advisories found; no evidence of enterprise or critical-infrastructure use [Likely] — grupapolsatplus.pl, interphone.com.pl
- Analyst note
- an FC:58:DF address most likely indicates a Polsat Box satellite decoder or home-internet modem owned by a Polish subscriber.