123.203.72.0/21 CIDR Lookup — 2.0K IPs Owned…

Reputation · trust score

A transparent 0–100 signal. Every entity starts at a neutral baseline of 65; threat-intel blocklists, exposure, reverse-DNS, routing and allocation each adjust it up or down. Higher is more trustworthy.

76/100

Moderate

How this score is built

Baseline (neutral) 65
Long-established allocation (20y) +6
Has a reverse-DNS (PTR) record +5
Trust score 76 / 100

Experimental · trust-vectors model v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →

Geolocation

First 256 of 2,048 IP addresses in 123.203.72.0/21

123.203.72.0 123.203.72.1 123.203.72.2 123.203.72.3 123.203.72.4 123.203.72.5 123.203.72.6 123.203.72.7 123.203.72.8 123.203.72.9 123.203.72.10 123.203.72.11 123.203.72.12 123.203.72.13 123.203.72.14 123.203.72.15 123.203.72.16 123.203.72.17 123.203.72.18 123.203.72.19 123.203.72.20 123.203.72.21 123.203.72.22 123.203.72.23 123.203.72.24 123.203.72.25 123.203.72.26 123.203.72.27 123.203.72.28 123.203.72.29 123.203.72.30 123.203.72.31 123.203.72.32 123.203.72.33 123.203.72.34 123.203.72.35 123.203.72.36 123.203.72.37 123.203.72.38 123.203.72.39 123.203.72.40 123.203.72.41 123.203.72.42 123.203.72.43 123.203.72.44 123.203.72.45 123.203.72.46 123.203.72.47 123.203.72.48 123.203.72.49 123.203.72.50 123.203.72.51 123.203.72.52 123.203.72.53 123.203.72.54 123.203.72.55 123.203.72.56 123.203.72.57 123.203.72.58 123.203.72.59 123.203.72.60 123.203.72.61 123.203.72.62 123.203.72.63 123.203.72.64 123.203.72.65 123.203.72.66 123.203.72.67 123.203.72.68 123.203.72.69 123.203.72.70 123.203.72.71 123.203.72.72 123.203.72.73 123.203.72.74 123.203.72.75 123.203.72.76 123.203.72.77 123.203.72.78 123.203.72.79 123.203.72.80 123.203.72.81 123.203.72.82 123.203.72.83 123.203.72.84 123.203.72.85 123.203.72.86 123.203.72.87 123.203.72.88 123.203.72.89 123.203.72.90 123.203.72.91 123.203.72.92 123.203.72.93 123.203.72.94 123.203.72.95 123.203.72.96 123.203.72.97 123.203.72.98 123.203.72.99 123.203.72.100 123.203.72.101 123.203.72.102 123.203.72.103 123.203.72.104 123.203.72.105 123.203.72.106 123.203.72.107 123.203.72.108 123.203.72.109 123.203.72.110 123.203.72.111 123.203.72.112 123.203.72.113 123.203.72.114 123.203.72.115 123.203.72.116 123.203.72.117 123.203.72.118 123.203.72.119 123.203.72.120 123.203.72.121 123.203.72.122 123.203.72.123 123.203.72.124 123.203.72.125 123.203.72.126 123.203.72.127 123.203.72.128 123.203.72.129 123.203.72.130 123.203.72.131 123.203.72.132 123.203.72.133 123.203.72.134 123.203.72.135 123.203.72.136 123.203.72.137 123.203.72.138 123.203.72.139 123.203.72.140 123.203.72.141 123.203.72.142 123.203.72.143 123.203.72.144 123.203.72.145 123.203.72.146 123.203.72.147 123.203.72.148 123.203.72.149 123.203.72.150 123.203.72.151 123.203.72.152 123.203.72.153 123.203.72.154 123.203.72.155 123.203.72.156 123.203.72.157 123.203.72.158 123.203.72.159 123.203.72.160 123.203.72.161 123.203.72.162 123.203.72.163 123.203.72.164 123.203.72.165 123.203.72.166 123.203.72.167 123.203.72.168 123.203.72.169 123.203.72.170 123.203.72.171 123.203.72.172 123.203.72.173 123.203.72.174 123.203.72.175 123.203.72.176 123.203.72.177 123.203.72.178 123.203.72.179 123.203.72.180 123.203.72.181 123.203.72.182 123.203.72.183 123.203.72.184 123.203.72.185 123.203.72.186 123.203.72.187 123.203.72.188 123.203.72.189 123.203.72.190 123.203.72.191 123.203.72.192 123.203.72.193 123.203.72.194 123.203.72.195 123.203.72.196 123.203.72.197 123.203.72.198 123.203.72.199 123.203.72.200 123.203.72.201 123.203.72.202 123.203.72.203 123.203.72.204 123.203.72.205 123.203.72.206 123.203.72.207 123.203.72.208 123.203.72.209 123.203.72.210 123.203.72.211 123.203.72.212 123.203.72.213 123.203.72.214 123.203.72.215 123.203.72.216 123.203.72.217 123.203.72.218 123.203.72.219 123.203.72.220 123.203.72.221 123.203.72.222 123.203.72.223 123.203.72.224 123.203.72.225 123.203.72.226 123.203.72.227 123.203.72.228 123.203.72.229 123.203.72.230 123.203.72.231 123.203.72.232 123.203.72.233 123.203.72.234 123.203.72.235 123.203.72.236 123.203.72.237 123.203.72.238 123.203.72.239 123.203.72.240 123.203.72.241 123.203.72.242 123.203.72.243 123.203.72.244 123.203.72.245 123.203.72.246 123.203.72.247 123.203.72.248 123.203.72.249 123.203.72.250 123.203.72.251 123.203.72.252 123.203.72.253 123.203.72.254 123.203.72.255 + 1.8K more (range too large to list inline)

BGP Routing

Live BGP anomalies →

Not announced as an exact prefix — covered by the announced supernet 123.203.64.0/18.

Announced prefix

123.203.64.0/18

Origin AS

AS9269

Announcement samples

4,779

Last seen

2026-07-18 11:59:44

Frequently Asked Questions

What is 123.203.72.0/21?

123.203.72.0/21 is a CIDR network block containing 2,048 IPv4 addresses (from 123.203.72.0 to 123.203.79.255). CIDR notation combines an IP address with a prefix length to define a range of addresses.

Who owns the 123.203.72.0/21 network?

The 123.203.72.0/21 range is allocated to Hong Kong Broadband Network Ltd. and announced via AS9269 from Hong Kong.