Communications & Power Industries (CPI) — 3 prefixes (MA-L)

A MAC address starting with 00:0B:4E, 00:0C:0D, or 00:16:3B belongs to Communications & Power Industries (CPI), a manufacturer of vacuum electron devices, solid-state RF amplifiers, and satellite-communications equipment headquartered in Palo Alto, California — typically seen on satcom traveling-wave-tube amplifiers (TWTAs) and other RF/microwave gear that exposes a network-connected monitor-and-control interface.

CPI holds three separate full MA-L (/24) registrations, each tied to a different facility: 00:16:3B to State College, PA; 00:0C:0D to the Palo Alto, CA Satcom Division; and 00:0B:4E to Plano, TX. All three are full OUI assignments, not sub-allocations under a shared IEEE base, so each independently and reliably identifies CPI hardware.

CPI's flagship satcom amplifiers — the Ka-band TL07KO-A1 and Ku-band T07UO-A1 TWTAs among them — ship with an integrated Ethernet interface, embedded web server, and SNMP v1/v2/v3 support for remote monitor-and-control, which is the plausible device context for equipment carrying a MAC under these blocks. CPI's broader catalog also spans klystrons, magnetrons, radar/electronic-warfare subsystems, antenna systems, and medical x-ray generators.

Two caveats apply. Third-party lookup sites show "initial registration" dates for these prefixes (2002–2005), but IEEE's own registry publishes no date field at all, so no registration date should be attributed to IEEE here. Separately, the registry also carries an unrelated row for the bare abbreviation "CPI" (EC:7D:9D) at a Malvern, PA address with no confirmed tie to Communications & Power Industries — it is not part of this vendor's prefix set.

IEEE assignment

3 prefixes → Communications & Power Industries, MA-L [Confirmed] — the IEEE MA-L registry 00163B, the IEEE MA-L registry 000C0D, the IEEE MA-L registry 000B4E

Registry / block size

MA-L (24-bit OUI); 3 separate full /24 blocks, no MA-M or 36-bit registrations found [Confirmed] — the IEEE MA-L registry, the IEEE MA-M registry, the IEEE MA-S registry

HQ / addresses

811 Hansen Way MS S-600, Palo Alto, CA 94303, US (Satcom Division, registrant of 00:0C:0D); also Suite, 60 Decibel Road, State College, PA 16801, US (00:16:3B); and 1000 Klein Road, Plano, TX 75074, US (00:0B:4E) [Confirmed] — the IEEE MA-L registry

Company status

active [Confirmed] — https://www.cpii.com/

Device types

satcom TWTAs, vacuum electron devices, solid-state amplifiers, radar/electronic-warfare subsystems, antenna systems, medical x-ray generators [Confirmed] — https://www.cpii.com/

Notable products

TL07KO-A1 (Ka-band TWTA), T07UO-A1 (Ku-band TWTA) [Confirmed] — https://www.cpii.com/docs/datasheets/819/MKT-603%20TL07KO-A1%20750%20W%20Ka-Band%20TWTA.pdf, https://esatcom.com/twtas/623-cpi-t07uo-a1.html

Verified sample prefixes (all MA-L, Communications & Power Industries)

00:0B:4E, 00:0C:0D, 00:16:3B [Confirmed] — the IEEE MA-L registry

Corporate history

CPI formed 1995 from the acquisition of Varian Associates' microwave/electron-device business (Varian's klystron work traces to 1948); no verified separate OUI held by Varian Associates was found [Likely] — https://en.wikipedia.org/wiki/CPI_International, https://www.cpii.com/history/

Special note

Third-party lookup tools (e.g. maclookup.app) show "initial registration" dates of 2002–2005 for these three prefixes; IEEE's public OUI data carries no date field, so no registration date is attributable to IEEE. Also, the IEEE MA-L registry row EC7D9D (bare "CPI", Malvern, PA) is a separate, unverified registrant not included in this vendor's prefix set.

[Confirmed] — the IEEE MA-L registry

Related vendors

Varian Associates (predecessor microwave/electron-device business; no verified independent OUI) [Likely] — https://en.wikipedia.org/wiki/CPI_International

Analyst note

Each of the three blocks is a full IEEE registration to CPI, not a sub-allocation under a shared base, so a MAC starting with any of them reliably indicates CPI-manufactured equipment — most plausibly a satcom TWTA or related RF/microwave device with a network M&C interface — though it does not pin down a specific model. No CVE naming Communications & Power Industries or its TWTA line was found in general web/CVE-adjacent search as of an August 2026 search; this is a sourced negative, not an exhaustive database clearance.

[Likely] — https://www.cisa.gov/news-events/ics-advisories