AS6453

AS6453 is the global Tier-1 transit backbone of Tata Communications, registered under ARIN to the company's America entity and operated as a worldwide settlement-free network. It is the descendant of Teleglobe's international carrier business: Tata's VSNL acquired Teleglobe in 2005–2006 and rebranded the combined operator as Tata Communications in 2008, with AS6453 carried forward as the global AS with worldwide reach. In CAIDA AS Rank it sits at #7 globally, with a customer cone of roughly 21,929 ASNs, ~536,952 prefixes, and ~1.11 billion addresses, and an AS degree near 665 (about 599 customers, 66 peers, and zero providers at the global level). Analysts should distinguish this global backbone from its India-facing sibling AS4755 (Tata Communications / formerly VSNL, registered through APNIC), which serves Indian access/enterprise customers, ranks around CAIDA #34, and announces a couple thousand prefixes; AS6453 and AS4755 are top mutual peers but play different roles. As a transit backbone, AS6453 originates very little end-user space, so it appears in AS paths as upstream and any abuse signal belongs to the downstream customer rather than to Tata.

Operator

Tata Communications (America) Inc. / Tata Communications Ltd (ARIN OrgId TCA-51) [Confirmed] — ARIN RDAP/WHOIS

Country / RIR

US (America entity for the global backbone ASN), ARIN [Confirmed] — ARIN RDAP

Allocated

1996-04-18 (ARIN ASN RegDate; ASHandle AS6453, updated 2014-04-22) [Confirmed] — ARIN RDAP

Org status

renamed lineage — VSNL acquired Teleglobe (announced 2005-07-25, ~$4.50/share, closed Feb 2006); VSNL renamed Tata Communications in 2008; AS6453 remains the global AS — en.wikipedia.org/wiki/Tata_Communications, sec.gov

Security/abuse context

Tier-1 transit; abuse attaches to downstream customers, not the backbone. Some IPs carry anycast/crawler tags from third parties. No notable public abuse signal attributable to the backbone itself as of 2026-06-04 — ipinfo.io

Network & routing

Network type

transit-backbone (Tier-1) [Confirmed] — CAIDA + PeeringDB

Size

CAIDA AS Rank #7 globally — customer cone ~21,929 ASNs / ~536,952 prefixes / ~1,114,259,485 addresses; AS degree ~665 global (~599 customers, ~66 peers, 0 providers; transit degree ~660); originated prefixes per current snapshots ~121 IPv4 / ~12 IPv6 (bgp.tools), higher counts in some historical views — asrank.caida.org/asns/6453, bgp.he.net/AS6453, bgp.tools/as/6453 (2026-06)

Routing/peering

functionally transit-free Tier-1 at the global level (bgp.tools also lists ~14 upstreams in some views); ~689 peers — bgp.tools, peeringdb.com/net/437

Notable usage

global Tier-1 transit backbone (ex-Teleglobe), worldwide reach — tatacommunications.com

Related ASNs

AS4755 (Tata Communications / formerly VSNL, India-facing; CAIDA #34; as-set AS-VSNL-IN)

Analyst note

Global transit backbone (ex-Teleglobe); appears in AS paths as upstream. Distinguish the global AS6453 from the India-facing AS4755.