AS517

AS517 is a RIPE-registered autonomous system currently held by GTT Communications, Inc., but it is not GTT's active operational network — that role belongs to AS3257, GTT's Tier-1 global backbone ASN. RIPE RDAP records the autnum's top-level registration event as 2002-08-01, with a last-changed timestamp of 2022-10-31, and the object is maintained under RIPE-NCC-LEGACY-MNT, marking it as a legacy allocation that predates the modern RIR framework and traces back to the ARIN-attributed AS1–AS1876 block. Historical routing-registry context (a 1997 NANOG CIDR Report archive) associates AS517 with Xlink, a pioneering German ISP founded in 1984 and a founding RIPE member in 1989, suggesting AS517 reached GTT through one or more acquisitions of European carrier assets rather than direct original allocation to GTT. Operationally, AS517 has been invisible in the global BGP table since March 1, 2021: RIPEstat shows 0 of 327 IPv4 and 0 of 321 IPv6 RIS peers currently observing it, and CAIDA AS Rank places it at 79,459 with a singleton customer cone (1 ASN, 0 prefixes, 0 addresses) and zero customer/peer/provider degree. No public abuse, hijack, or blocklist signal specific to AS517 was found as of 2026-07-10.

AS name

UNSPECIFIED (no descriptive AS-name set in the RDAP record) [Confirmed] — https://rdap.db.ripe.net/autnum/517

RIR / status

RIPE NCC, legacy allocation maintained under RIPE-NCC-LEGACY-MNT; registry-level status "active" (a valid, non-revoked record) even though routing is dormant [Confirmed] — https://rdap.db.ripe.net/autnum/517

Allocated

2002-08-01 — the autnum object's own top-level RDAP "registration" event (RIPE), not a nested entity/org date [Confirmed]; last changed 2022-10-31 [Confirmed] — https://rdap.db.ripe.net/autnum/517

Country / geo footprint

Germany, per both the RIPE registrant address and the last observed BGP announcement origin; GTT Communications Inc. itself is US-headquartered — flagged range: one aggregator (ipinfo.io) separately labels country "United States," but RIPE RDAP (first-party) is authoritative and says Germany [Confirmed for RIPE record; Likely for the US/DE dual reading] — https://rdap.db.ripe.net/autnum/517, https://bgp.he.net/AS517

Org status

GTT Communications, Inc. is an active, publicly-traded (historically) US telecom operator headquartered in the US, with the AS517 registrant org record (ORG-GCI2-RIPE) address in Neu-Isenburg, Germany [Confirmed] — https://rdap.db.ripe.net/autnum/517, https://www.gtt.net/us-en/about-us/

Website

https://www.gtt.net [Confirmed]

Security/abuse context (NEUTRAL, DATED)

no notable public abuse, hijack, or blocklist signal found for AS517 specifically as of 2026-07-10 — absent from Spamhaus ASN-DROP (plaintext and JSON, live-checked) and no NANOG/seclists thread naming AS517 for misconduct. A separately-documented 2020 BGP route-leak incident (Rostelecom hijack propagation, April 2020) involves GTT Communications' network generally; sources describing that incident do not specify AS517 as the propagating ASN, and given AS517's near-zero routing footprint it should not be attributed to AS517 without a source that names it directly [Likely for the "no AS517-specific signal" finding; the 2020 incident is noted for context only, not attributed to AS517] — https://www.spamhaus.org/drop/asndrop.json, https://seclists.org/nanog/1997/Feb/360, https://manrs.org/2020/04/not-just-another-bgp-hijack/

Network & routing

Network type / operator relationship

legacy/inactive ASN administratively folded under GTT's primary network and maintainer infrastructure (AS3257-NET-MNT, AS3257-ROOT-MNT); GTT's own site describes its live backbone (AS3257) as a Tier-1 global IP network with 400+ PoPs and 300+ Tbps IP edge capacity — that description applies to AS3257, not to the dormant AS517

[Confirmed] — https://www.gtt.net/us-en/about-us/, https://www.peeringdb.com/net/14

Routing status

not visible in the global BGP table since March 1, 2021; 0 of 327 IPv4 / 0 of 321 IPv6 RIS peers currently observe it; historically originated approximately two IPv4 /24s (192.129.32.0/24, 192.129.33.0/24, both now flagged as bogons) [Confirmed for current 0; Likely for the historical prefix count/blocks, sourced via secondary aggregator] — https://stat.ripe.net/data/routing-status/data.json?resource=517, https://bgp.he.net/AS517

Peering policy

AS517 has no independent PeeringDB record (peeringdb.com/asn/517 returns 404) and is not separately listed as an active peering ASN, so no policy is attributable to it directly; GTT's corporate policy (associated with active ASN AS3257) is published as settlement-free subject to geographic/technical/NDA requirements, while PeeringDB separately tags GTT's network "Restrictive" with a ratio requirement [Likely, and explicitly not confirmed to apply to AS517 itself] — https://www.gtt.net/peering/, https://www.peeringdb.com/net/14, https://www.peeringdb.com/asn/517

RPKI

not evaluable — zero prefixes currently announced, so there is nothing to validate against ROAs [Confirmed] — https://stat.ripe.net/data/routing-status/data.json?resource=517

ASN / registrant

AS517, registered to GTT Communications Inc. (RIPE org handle ORG-GCI2-RIPE), Frankfurter Strasse 227, 63263 Neu-Isenburg, Germany; abuse contact abuse@gtt.net [Confirmed] — https://rdap.db.ripe.net/autnum/517

Historical block lineage

sits inside IANA's pre-RIR centrally-assigned AS1–AS1876 block, originally attributed to ARIN before the RIR system split geographically [Confirmed] — https://stat.ripe.net/data/as-overview/data.json?resource=517

Historical original holder

Xlink (eXtended Local Informatics Network Karlsruhe), a German ISP founded 1984 and a founding RIPE member (1989); AS-KPN IRR as-set membership and a historical AS286 (KPN International) peering relationship both point toward a KPN Eurorings/International lineage, plausibly absorbed into GTT via GTT's 2016 acquisition of KPN International — RDAP itself does not state this chain explicitly

[Likely] — https://bgp.he.net/irr/as-set/AS-KPN, https://en.wikipedia.org/wiki/XLINK_(Internet_service_provider)

Ranking / cone

CAIDA AS Rank 79,459; singleton customer cone (1 ASN, 0 prefixes, 0 addresses); AS degree customer 0 / peer 0 / provider 0 [Confirmed] — https://asrank.caida.org/asns/517

Peers (historical, not live)

AS286 / KPN International B.V., surfaced via AS-KPN IRR as-set membership; no relationship has been live since the ASN went dark [Likely] — https://bgp.he.net/AS517

Analyst note

AS517 is best understood as a dormant legacy ASN carried in GTT's portfolio (likely via a KPN-lineage acquisition) rather than an operationally distinct network; all live-routing questions about GTT should point to AS3257, not AS517.