AS63

AS63 is a legacy allocation registered under ARIN to the Massachusetts Institute of Technology, specifically its Lincoln Laboratory sub-org in Lexington, MA (org MIT-Z, address "Lincoln Laboratory"). RFC 1020 (1987) lists AS63 as "LL-MI," confirming this is the genuine MIT Lincoln Laboratory ASN — distinct from AS40 (MIT-TEST) and AS3 (MIT-GATEWAYS, the main campus network). MIT Lincoln Laboratory is a federally funded research and development center at Hanscom AFB, Lexington, MA, established in 1951 to develop a U.S. air-defense system (the SAGE program). It is actively announcing: as of June 2026 about six IPv4 prefixes and no IPv6 (~67,584 addresses), with upstream Unitas Global (AS13789) and peers including Harvard University (AS10578); its prefixes appear as unauthenticated IRR (no valid ROA observed). The ARIN ASN RegDate is 1986-02-24 (the MIT-Z org RegDate of 2023-11-30 is a registry refresh). For triage this is a clean institutional/FFRDC network, actively routed and distinct from MIT's main AS3. No notable public abuse signal was found as of June 2026.

Operator

Massachusetts Institute of Technology — Lincoln Laboratory (ARIN OrgId MIT-Z, Lexington, MA 02173) [Confirmed] — ARIN RDAP

Country / RIR

US, ARIN [Confirmed]

Allocated

ARIN ASN RegDate 1986-02-24 (updated 2023-12-04; org MIT-Z RegDate 2023-11-30 is a registry refresh) [Confirmed]

Org status

active — ll.mit.edu

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-08; clean institutional/FFRDC network — bgp.tools

Network & routing

Network type

FFRDC / research-defense [Confirmed]

Size

~6 IPv4 prefixes, 0 IPv6 (~67,584 addrs) — bgp.tools / bgpview.io (2026-06)

Routing/peering

actively announcing; upstream Unitas Global (AS13789), peers incl. Harvard (AS10578); RPKI unauthenticated IRR (no valid ROA observed) — bgp.tools

Notable usage

[historical, RFC 1020 + ARIN] AS63 "LL-MI" = the genuine MIT Lincoln Laboratory ASN (FFRDC, Lexington MA; established 1951 for the SAGE air-defense program), distinct from AS40 (MIT-TEST) and AS3 (MIT-GATEWAYS) — ll.mit.edu

Related ASNs

AS3 (MIT-GATEWAYS, main MIT campus), AS40 (MIT-TEST) [Confirmed]

Analyst note

The genuine MIT Lincoln Laboratory ASN (not the plain MIT-TEST AS40); actively routed, low-risk FFRDC network.