Ascend Communications, Inc. — 2 prefixes (MA-L)

Ascend Communications was an Alameda, California WAN and remote-access equipment maker that held two distinct MA-L OUI blocks — 00:C0:7B and 00:D0:52 — both registered to "ASCEND COMMUNICATIONS, INC." at 1701 Harbor Bay Parkway, Alameda, CA. Founded in 1988 and public from 1994, the company built the Pipeline series of ISDN bridge/routers for small offices and the MAX 4000 and MAX TNT WAN access concentrators that large ISPs (AOL, EarthLink, UUNET, Demon Internet) used to terminate mass dial-up and ISDN lines during the 1990s internet build-out. It acquired Cascade Communications (1997) and Stratus Computer (1998) before being acquired by Lucent Technologies in a roughly $24 billion merger in 1999. The two separate MA-L allocations are consistent with a real, growing hardware manufacturer that needed additional address space over time — not a one-off shell registration. Both product lines are now long obsolete; a MAC in either block reliably identifies legacy Ascend/Lucent-era access gear rather than any current-production device.

IEEE assignment

2 MA-L prefixes → ASCEND COMMUNICATIONS, INC., 1701 Harbor Bay Parkway, Alameda, CA, US 94502 [Confirmed] — IEEE MA-L (: 00-C0-7B, 00-D0-52)

Registry / block size

MA-L (24-bit OUI); two blocks assigned [Confirmed] — the IEEE MA-L registry. No MA-M (the IEEE MA-M registry) or MA-S (the IEEE MA-S registry) entry exists for this org [Confirmed] — direct grep of cached registries

Verified prefixes (both MA-L, ASCEND COMMUNICATIONS, INC.)

00:C0:7B, 00:D0:52 [Confirmed] — the IEEE MA-L registry

HQ / country

1701 Harbor Bay Parkway, Alameda, CA 94502, US (registry address) [Confirmed] — IEEE MA-L

Company status

defunct — acquired by Lucent Technologies in 1999 (~$24B merger) [Confirmed] — en.wikipedia.org/wiki/Ascend_Communications, lightwaveonline.com

Device types

ISDN bridge/routers (Pipeline series), WAN access switches / dial-up concentrators (MAX 4000, MAX TNT) [Confirmed] — trinityos.com/ISDN/ascend.html, networking.ringofsaturn.com

Notable products

Pipeline 25/50/75/130 ISDN routers; MAX 4000 and MAX TNT dial/ISDN access concentrators [Confirmed] — trinityos.com, recycledgoods.com resale listing

Corporate history

founded 1988; IPO 1994; acquired Cascade Communications 1997 and Stratus Computer 1998; acquired by Lucent 1999 [Confirmed] — fundinguniverse.com, referenceforbusiness.com

No IEEE registration date

IEEE publishes NO assignment/registration date for OUI/MA-L blocks; third-party "date registered" values (e.g. maclookup.app's 1998-04-22 for 00:C0:7B, 2000-11-09 for 00:D0:52) are database artifacts, not IEEE facts

[Confirmed] — IEEE the IEEE MA-L registry columns are Registry/Assignment/Org Name/Org Address only

Related / not-a-match

"Ascend Networks, Inc." (OUI 00:18:2C, Taipei, TW) is a different legal entity, not this company [Confirmed] — the IEEE MA-L registry

Security / abuse context

Unknown — no sourced CVE, botnet, or abuse reporting tied to these OUIs or the legacy Pipeline/MAX lines was located; devices are obsolete since the 1999 acquisition [Unknown] — no evidence found in this pass

Analyst note

A MAC in 00:C0:7B or 00:D0:52 identifies legacy 1990s Ascend/Lucent-era WAN access hardware; both blocks predate MAC randomization concerns (globally-administered, wired/dial gear)