asn.dev

Autonomous system

AS39135 FIBER1

Unclassified RIPE

IPv4 addresses 9.98K 4 prefixes
IPv6 prefixes 0 counted as prefixes, not addresses
Countries 1 mostly BG
Exchanges 0 recorded by PCH
Upstreams 2 0 downstream
Flagged prefixes 0 none

Summary

Fiber 1

Bulgaria · AI-generated

residential isp bg

The AS handle FIBER1 is operated by Fiber 1 Ltd.

What it's used for

  • The address space carries residential and business internet traffic, evidenced by reverse DNS entries such as ip-77.238.87.254.fiber1.bg and 212-5-129-64.ip.btc-net.bg.
  • The network announces 9,984 IPv4 addresses across 4 prefixes and maintains 2 observed neighbours, a ratio indicative of an access or eyeball network rather than a transit provider.
  • As a subscription-based service provider in Sofia, the traffic consists primarily of subscriber internet access and associated media delivery.

Notable

  • Registrants for the majority of prefixes align with the announcer, specifically Fiber 1 Ltd. for 77.238.64.0/19 and 185.73.56.0/22, while 212.5.129.0/24 is registered to Vivacom Bulgaria EAD.
  • The address inventory is composed of four distinct IPv4 blocks, with the largest being 77.238.64.0/19, and no IPv6 prefixes are currently announced.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.

Interconnection

Peering at a glance

Full topology · Graph

Internet exchanges

No exchange port on file. Many exchanges publish no participant list, so this is not proof of absence.

Transit providers

2 upstream, 0 downstream and 2 adjacent networks observed; most-used upstreams first.

ASNetworkPaths seen
AS57344Telehouse EAD239
AS31287IPACCT CABLE Ltd9

Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-11, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.

Address space

Summary

Shape and geography

IPv4 4 prefixes · 9.98K addresses IPv6 0 prefixes

CountryNamePrefixes
BGBulgaria4

Registry

Allocation record

RIPE · via Atlas (registry + RDAP)
Registry
RIPE
Handle
AS39135
Registry name
FIBER1BG
Registrant
FIBER1-MNT
Abuse contact
manager@fiber1.bg
Registered
2005-12-16
Last changed
2018-09-04
Allocation
allocated

Routing security

RPKI and IRR

Full detail
RPKI
100% valid · 4 valid, 0 with no ROA
ROAs
5 authorising AS39135
ASPA
no ASPA record
IRR
100% registered · 4 of 4 announcements
Route objects
7 naming AS39135

Reputation

Classification and threat

Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.

Spamhaus DROP

Not on ASN-DROP The network as a whole is not listed.

No DROP prefixes None of its announced space is on the DROP prefix list.

Spamhaus DROP ("Don't Route Or Peer") lists space and networks run by, or hijacked for, spam and cybercrime operations: 432 networks and 1,768 prefixes, as published 2026-10-12. A short, high-confidence list, so a match is worth taking seriously, and absence from it says little on its own.

FBI IC3

No IC3 indicators Nothing from the FBI IC3 feed.

IC3 threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.

Elsewhere

Cross-check