$ query “AS1221” --type=asn → 1 result(s)
AS1221 — ASN-TELSTRA
Telstra Limited
AS1221 is a major transit provider operated by Telstra Limited, based in Australia. The network announces a whopping 13.4 million IPv4 addresses (0.36% of routable IPv4 space), including a /11. Supports IPv6.
- Top 5% — Top 5% of all autonomous systems by reach and degree
- Space Overlord — Over 10 million IPv4 addresses
- #84 by Reach — Top 100 by customer cone size
- #1 in Australia — Top 10 by reach within country
Basic Information
- Country
- 🇦🇺 Australia
- Category
- Internet Service Provider
- Network Role
- Major Transit
- Data Origin
- Authoritative — Metadata from authoritative RIR registry (ARIN, RIPE, APNIC, etc.)
- Last Changed
- March 04, 2026
- Last Seen
- March 04, 2026
Prefix Summary
- IPv4 Prefixes (raw / aggregated)
- 288 / 240
- IPv6 Prefixes (raw / aggregated)
- 2 / 2
- IPv4 Addresses
- 13 402 112
- Largest IPv4 Prefix
- /11 (2 097 152 addresses)
- Largest IPv6 Prefix
- /20
- Geolocated Countries
- 🇦🇺 AU (225 IPs), 🇵🇬 PG (2 IPs), 🇺🇸 US (12 IPs), 🇳🇿 NZ, 🇨🇭 CH
- Prefix Changed
- March 04, 2026
Reputation
- Reputation
- Good — 139 flagged IPs out of 13 402 112 total (0.00%)
Connectivity Summary
- Upstream Providers
- 1 upstream autonomous systems providing transit
- Peers
- 18 autonomous systems exchanging traffic without transit fees
- Downstream Customers
- 284 downstream autonomous systems buying transit
- Degree
- 303 unique BGP neighbors (providers + customers + peers)
- Reach
- 37 175 — customer cone size measuring network influence
- Degree Rank
- #430
- Reach Rank
- #84
- Country Rank
- #1
Upstream Providers (1)
- AS4637 — ASN-TELSTRA-GLOBAL
Prefix Lists
IPv4 Prefixes (288 total)
- 1.128.0.0/11 (2 097 152 addresses)
- 101.160.0.0/11 (2 097 152 addresses)
- 58.160.0.0/12 (1 048 576 addresses)
- 121.208.0.0/12 (1 048 576 addresses)
- 124.176.0.0/12 (1 048 576 addresses)
- 1.120.0.0/13 (524 288 addresses)
- 60.224.0.0/13 (524 288 addresses)
- 110.144.0.0/13 (524 288 addresses)
- 120.144.0.0/13 (524 288 addresses)
- 203.40.0.0/13 (524 288 addresses)
- 110.140.0.0/14 (262 144 addresses)
- 120.152.0.0/14 (262 144 addresses)
- 144.132.0.0/14 (262 144 addresses)
- 203.36.0.0/14 (262 144 addresses)
- 203.48.0.0/14 (262 144 addresses)
- 120.156.0.0/15 (131 072 addresses)
- 123.210.0.0/15 (131 072 addresses)
- 144.136.0.0/15 (131 072 addresses)
- 203.52.0.0/15 (131 072 addresses)
- 101.103.0.0/16 (65 536 addresses)
- 120.158.0.0/16 (65 536 addresses)
- 123.209.0.0/16 (65 536 addresses)
- 125.255.0.0/16 (65 536 addresses)
- 137.147.0.0/16 (65 536 addresses)
- 138.130.0.0/16 (65 536 addresses)
- 138.217.0.0/16 (65 536 addresses)
- 139.130.0.0/16 (65 536 addresses)
- 139.134.0.0/16 (65 536 addresses)
- 139.168.0.0/16 (65 536 addresses)
- 143.238.0.0/16 (65 536 addresses)
- 144.131.0.0/16 (65 536 addresses)
- 144.139.0.0/16 (65 536 addresses)
- 144.140.0.0/16 (65 536 addresses)
- 147.69.0.0/16 (65 536 addresses)
- 149.135.0.0/16 (65 536 addresses)
- 165.228.0.0/16 (65 536 addresses)
- 203.35.0.0/16 (65 536 addresses)
- 203.54.0.0/16 (65 536 addresses)
- 61.9.128.0/17 (32 768 addresses)
- 144.130.0.0/17 (32 768 addresses)
- 203.58.128.0/17 (32 768 addresses)
- 144.130.192.0/18 (16 384 addresses)
- 202.12.128.0/18 (16 384 addresses)
- 203.27.128.0/18 (16 384 addresses)
- 203.58.64.0/18 (16 384 addresses)
- 203.143.192.0/18 (16 384 addresses)
- 61.8.0.0/19 (8 192 addresses)
- 144.130.160.0/19 (8 192 addresses)
- 192.74.160.0/19 (8 192 addresses)
- 192.148.128.0/19 (8 192 addresses)
IPv6 Prefixes (2 total)
- 2001:8000::/20
- 2401:a480::/48