ShenZhen C&D Electronics CO.Ltd. — assigned MAC prefixes; device unknown

A MAC address beginning with one of these prefixes matches an IEEE registry assignment to ShenZhen C&D Electronics CO.Ltd.; the assignment alone does not identify a device or prove who deployed it. The company describes itself as an intelligent control product solutions provider, established in August 2004, with products spanning remote controls, HVAC, medical, smart home, furniture, and consumer electronics applications.

The two MA-L prefixes cover 24 initial bits, leaving 24 suffix bits (16,777,216 possible values each). The three MA-M prefixes cover 28 bits, leaving 20 suffix bits (1,048,576 possible values each). These are possible suffix values, not device or shipment counts. All five prefixes have Group and Local bits set to zero.

RFC 7042 says these two bits have special significance in MAC addresses and that assigned OUIs and longer MAC prefixes have the Local bit set to zero and the Group bit unspecified.

Changing either bit changes the prefix.

A match establishes only that the captured address begins with a listed assigned prefix. It does not establish a particular product, operating system, current vendor identity, traffic prevalence, or security status. For the /28 entries, compare the first 28 bits, including the leading nibble of the fourth octet.

Device identification

Unknown; the registry records do not map these prefixes to a device category. [Unknown] — https://standards-oui.ieee.org/oui/oui.csv

Company context

Intelligent control product solutions provider; established August 2004. [Confirmed] — https://en.cn-cdrc.com/Company_Introduction.html

Registry types

MA-L and MA-M, as shown in the IEEE assignment records. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv; https://standards-oui.ieee.org/oui28/mam.csv

Prefixes

48:EA:A9, E8:B4:AE, DC:E5:33:3/28, 34:D7:F5:1/28, 20:B3:7F:A/28, listed in the IEEE MA-L and MA-M assignment records. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv; https://standards-oui.ieee.org/oui28/mam.csv

Country

China, indicated by the IEEE assignment records. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv

Registry organization name

ShenZhen C&D Electronics CO.Ltd. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv

Device types

Unknown; no source maps a device category to these exact prefixes. [Unknown] — https://standards-oui.ieee.org/oui/oui.csv

Notable products

Remote controls; heating, ventilation, and air conditioning products; smart office; medical aesthetics; smart home; furniture electrification. [Confirmed] — https://en.cn-cdrc.com/Company_Introduction.html

Industry

Intelligent control product solutions and electronics manufacturing. [Confirmed] — https://en.cn-cdrc.com/Company_Introduction.html

Website

https://en.cn-cdrc.com/Company_Introduction.html [Confirmed] — https://en.cn-cdrc.com/Company_Introduction.html

Assignment date

Assignment dates are unavailable in these IEEE CSV records. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv

Prefix interpretation

The /24 entries match 24 initial bits and the /28 entries match 28; the remaining bits are suffix bits. Calculated from the five listed prefixes, each has Group bit 0 and Local bit 0; changing either bit produces a different prefix. [Confirmed] — https://standards-oui.ieee.org/oui/oui.csv; https://standards-oui.ieee.org/oui28/mam.csv; https://www.rfc-editor.org/rfc/rfc7042.txt