Larscom Incorporated — 2 prefixes (MA-L)

Larscom Incorporated was a Santa Clara / Milpitas, California WAN access-equipment manufacturer that holds two IEEE MA-L OUI blocks: 00-20-C8 (registry address 4600 Patrick Henry Drive, Santa Clara, CA 95054) and 00-60-AB (1845 McCandless Drive, Milpitas, CA 95035). The company built T1 and fractional-T1 network-access hardware — CSU/DSU units combined with multiplexers — its best-known line being the "Access-T" series that sat at the WAN edge of carrier, ISP, and enterprise premises through the late 1990s and early 2000s. That its first MA-L block was exhausted and a second allocated is itself corroborating evidence of a real, shipping hardware business rather than a bare paper registration. Larscom merged with VINA Technologies in 2003 and the combined entity was subsequently acquired in a 2004 merger involving Verilink Corporation, so the standalone brand is no longer active; Access-T units still surface today on the surplus and refurbished-telecom market. Because this is legacy DSU/CSU gear that largely predates the CVE/NVD program and has no evident modern internet-facing footprint, no Larscom-specific security advisory or CVE was found — a sourced null, not a claim of verified safety. Note that IEEE publishes no assignment dates for these OUIs, so no registration date is asserted here.

IEEE assignment

2 MA-L prefixes → LARSCOM INCORPORATED [Confirmed] — IEEE MA-L (:37809)

Prefix 00-20-C8

LARSCOM INCORPORATED, 4600 Patrick Henry Drive, Santa Clara, CA 95054, US [Confirmed] — IEEE MA-L

Prefix 00-60-AB

LARSCOM INCORPORATED, 1845 McCandless Drive, Milpitas, CA 95035, US [Confirmed] — IEEE MA-L

Registry / block size

MA-L (24-bit OUI) for both assignments; no MA-M or MA-S records exist for this vendor (no matches in the IEEE MA-M registry or the IEEE MA-S registry) [Confirmed] — IEEE registries (the cached registry snapshots)

HQ / country

Santa Clara / Milpitas, CA, US (two registry addresses) [Confirmed] — IEEE MA-L

Company status

inactive — merged with VINA Technologies (2003), combined entity acquired via a 2004 merger involving Verilink Corporation [Likely] — https://www.cbinsights.com/company/larscom, https://pitchbook.com/profiles/company/51216-85, https://www.crunchbase.com/organization/larscom

Device types

T1 / fractional-T1 WAN access equipment — CSU/DSU units with integrated multiplexer [Confirmed] — https://cybarcode.com/larscom/network_controllers/csu_dsu/access-t

Notable products

"Access-T" line (T1/fractional-T1 DSU/CSU + mux for WAN-edge network access) [Confirmed] — https://cybarcode.com/larscom/network_controllers/csu_dsu/access-t, https://www.hardwarejet.com/larscom-access-t-211.html

Security context

no Larscom-specific CVE or vendor advisory found; legacy DSU/CSU class largely predates the CVE/NVD program (est. 1999) with no evident internet-facing footprint [Unknown] — sourced null; no advisory located

IEEE assignment date

none published. IEEE public OUI data (the IEEE MA-L registry columns: Registry, Assignment, Organization Name, Organization Address) contains NO registration date; any "date registered" on third-party lookup tools is a database artifact, not an IEEE fact.

[Confirmed] — IEEE the IEEE MA-L registry schema

IANA Reference

blank / not applicable — OUIs are administered by IEEE, not IANA; no IANA RFC reference exists for this entry [Confirmed] — IEEE registry authority

Analyst note

A Larscom OUI on a captured MAC reliably identifies vintage Larscom WAN-access hardware; given the brand's ~2003–2004 wind-down, seeing one today most likely indicates legacy or surplus telecom gear rather than a current product.