Which company owns MAC address prefix 70:E8:43?

MAC address prefix 70:E8:43 is registered to Beijing C&W Optical Communication Technology Co.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 70:E8:43 has a network interface built by Beijing C&W Optical Communication Technology Co.,Ltd..

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 70:E8:43:00:00:00 that is 70:E8:43 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.

Beijing C&W Optical Communication Technology Co.,Ltd.

MAC address prefix 70:E8:43 is registered to Beijing C&W Optical Communication Technology Co.,Ltd. in the IEEE OUI registry. Any device whose MAC address begins with 70:E8:43 has a network interface built by Beijing C&W Optical Communication Technology Co.,Ltd.. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address — it covers every MAC from 70:E8:43:00:00:00 to 70:E8:43:FF:FF:FF.

OUI prefix: 70:E8:43
Hyphen form: 70-E8-43
MAC range: 70:E8:43:00:00:00 – 70:E8:43:FF:FF:FF
Addresses in block: 16,777,216
Organization: Beijing C&W Optical Communication Technology Co.,Ltd.
Address: 2/F Yufa Plaza, No.19 Xiaoying Beilu, Chaoyang District, Beijing CN 100101
Source: IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.

Assignment history (2)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2016-07-29Assigned to "Beijing C&W Optical Communication Technology Co.,Ltd."
archived source →
2026-07-17Assigned to "Beijing C&W Optical Communication Technology Co.,Ltd."

Nearby in the registry

The prefixes assigned immediately before and after 70:E8:43:

FAQ

Which company owns MAC address prefix 70:E8:43?: MAC address prefix 70:E8:43 is registered to Beijing C&W Optical Communication Technology Co.,Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 70:E8:43 has a network interface built by Beijing C&W Optical Communication Technology Co.,Ltd..
What is the OUI 70:E8:43?: 70:E8:43 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Beijing C&W Optical Communication Technology Co.,Ltd.. It covers every address from 70:E8:43:00:00:00 to 70:E8:43:FF:FF:FF, or 16,777,216 addresses in total. It is also written 70-E8-43.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 70:E8:43:00:00:00 that is 70:E8:43 — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.
Where is Beijing C&W Optical Communication Technology Co.,Ltd. located?: Beijing C&W Optical Communication Technology Co.,Ltd. is listed at 2/F Yufa Plaza, No.19 Xiaoying Beilu, Chaoyang District, Beijing CN 100101 in the IEEE OUI registry entry for 70:E8:43. This is the address the organization registered with the IEEE, which may differ from its current operating address.