IPv4 R&E Routing Table Report 22:20 GMT Sat 13 Dec, 2025 IPv4 BGP Table (R&E) as seen at ESnet. Report Website: https://bgp.nsrc.org/REN Detailed Analysis: https://bgp.nsrc.org/REN/ESnet/ Analysis Summary ---------------- BGP routing table entries examined: 18890 Prefixes after maximum aggregation (per Origin AS): 10226 Deaggregation factor: 1.85 Unique aggregates announced (without unneeded subnets): 11371 Number of IPv4 prefixes with a valid ROA: 8036 Number of IPv4 prefixes with an invalid ROA: 30 Number of IPv4 prefixes with no ROA: 10824 Total ASes present in the Internet Routing Table: 2660 Prefixes per ASN: 7.10 Origin-only ASes present in the Internet Routing Table: 2311 Origin ASes announcing only one prefix: 1040 Transit ASes present in the Internet Routing Table: 349 Transit-only ASes present in the Internet Routing Table: 44 Paths with bogon ASNs present in the IPv4 Routing Table: 0 Average AS path length visible in the Internet Routing Table: 3.9 Max AS path length visible: 16 Max AS path prepend of ASN (395156) 12 Prefixes from unregistered ASNs in the Routing Table: 12 Number of instances of unregistered ASNs: 12 Number of 32-bit ASNs allocated by the RIRs: 48196 Number of 32-bit ASNs visible in the Routing Table: 687 Prefixes from 32-bit ASNs in the Routing Table: 1889 Number of bogon 32-bit ASNs visible in the Routing Table: 0 Special use prefixes present in the Routing Table: 0 Prefixes being announced from unallocated address space: 3 Number of addresses announced to Internet: 167052544 Equivalent to 9 /8s, 245 /16s and 5 /24s Percentage of available address space announced: 4.5 Percentage of allocated address space announced: 4.5 Percentage of available address space allocated: 100.0 Percentage of address space in use by end-sites: 99.6 Total number of prefixes smaller than registry allocations: 2177 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 4605 Total APNIC prefixes after maximum aggregation: 2264 APNIC Deaggregation factor: 2.03 Prefixes being announced from the APNIC address blocks: 4604 Unique aggregates announced from the APNIC address blocks: 2543 APNIC Region origin ASes present in the Internet Routing Table: 575 APNIC Prefixes per ASN: 8.01 APNIC Region origin ASes announcing only one prefix: 237 APNIC Region transit ASes present in the Internet Routing Table: 51 Average APNIC Region AS path length visible: 3.6 Max APNIC Region AS path length visible: 12 Number of APNIC region 32-bit ASNs visible in the Routing Table: 232 Number of APNIC addresses announced to Internet: 35699712 Equivalent to 2 /8s, 32 /16s and 188 /24s APNIC AS Blocks 4608-4864, 7467-7722, 9216-10239, 17408-18431 (pre-ERX allocations) 23552-24575, 37888-38911, 45056-46079, 55296-56319, 58368-59391, 63488-64098, 64297-64395, 131072-155961 APNIC Address Blocks 1/8, 14/8, 27/8, 36/8, 39/8, 42/8, 43/8, 49/8, 58/8, 59/8, 60/8, 61/8, 101/8, 103/8, 106/8, 110/8, 111/8, 112/8, 113/8, 114/8, 115/8, 116/8, 117/8, 118/8, 119/8, 120/8, 121/8, 122/8, 123/8, 124/8, 125/8, 126/8, 133/8, 150/8, 153/8, 163/8, 171/8, 175/8, 180/8, 182/8, 183/8, 202/8, 203/8, 210/8, 211/8, 218/8, 219/8, 220/8, 221/8, 222/8, 223/8, ARIN Region Analysis Summary ---------------------------- Prefixes being announced by ARIN Region ASes: 8532 Total ARIN prefixes after maximum aggregation: 4663 ARIN Deaggregation factor: 1.83 Prefixes being announced from the ARIN address blocks: 8553 Unique aggregates announced from the ARIN address blocks: 5193 ARIN Region origin ASes present in the Internet Routing Table: 1271 ARIN Prefixes per ASN: 6.73 ARIN Region origin ASes announcing only one prefix: 453 ARIN Region transit ASes present in the Internet Routing Table: 153 Average ARIN Region AS path length visible: 4.0 Max ARIN Region AS path length visible: 16 Number of ARIN region 32-bit ASNs visible in the Routing Table: 227 Number of ARIN addresses announced to Internet: 72098816 Equivalent to 4 /8s, 76 /16s and 36 /24s ARIN AS Blocks 1-1876, 1902-2042, 2044-2046, 2048-2106 (pre-ERX allocations) 2138-2584, 2615-2772, 2823-2829, 2880-3153 3354-4607, 4865-5119, 5632-6655, 6912-7466 7723-8191, 10240-12287, 13312-15359, 16384-17407 18432-20479, 21504-23551, 25600-26591, 26624-27647, 29696-30719, 31744-33791 35840-36863, 39936-40959, 46080-47103 53248-55295, 62464-63487, 64198-64296, 393216-402332 ARIN Address Blocks 3/8, 4/8, 6/8, 7/8, 8/8, 9/8, 11/8, 12/8, 13/8, 15/8, 16/8, 17/8, 18/8, 19/8, 20/8, 21/8, 22/8, 23/8, 24/8, 26/8, 28/8, 29/8, 30/8, 32/8, 33/8, 34/8, 35/8, 38/8, 40/8, 44/8, 45/8, 47/8, 48/8, 50/8, 52/8, 54/8, 55/8, 56/8, 63/8, 64/8, 65/8, 66/8, 67/8, 68/8, 69/8, 70/8, 71/8, 72/8, 73/8, 74/8, 75/8, 76/8, 96/8, 97/8, 98/8, 99/8, 100/8, 104/8, 107/8, 108/8, 128/8, 129/8, 130/8, 131/8, 132/8, 134/8, 135/8, 136/8, 137/8, 138/8, 139/8, 140/8, 142/8, 143/8, 144/8, 146/8, 147/8, 148/8, 149/8, 152/8, 155/8, 156/8, 157/8, 158/8, 159/8, 160/8, 161/8, 162/8, 164/8, 165/8, 166/8, 167/8, 168/8, 169/8, 170/8, 172/8, 173/8, 174/8, 184/8, 192/8, 198/8, 199/8, 204/8, 205/8, 206/8, 207/8, 208/8, 209/8, 214/8, 215/8, 216/8, RIPE Region Analysis Summary ---------------------------- Prefixes being announced by RIPE Region ASes: 3294 Total RIPE prefixes after maximum aggregation: 2630 RIPE Deaggregation factor: 1.25 Prefixes being announced from the RIPE address blocks: 3285 Unique aggregates announced from the RIPE address blocks: 2715 RIPE Region origin ASes present in the Internet Routing Table: 599 RIPE Prefixes per ASN: 5.48 RIPE Region origin ASes announcing only one prefix: 276 RIPE Region transit ASes present in the Internet Routing Table: 102 Average RIPE Region AS path length visible: 3.6 Max RIPE Region AS path length visible: 13 Number of RIPE region 32-bit ASNs visible in the Routing Table: 148 Number of RIPE addresses announced to Internet: 52903424 Equivalent to 3 /8s, 39 /16s and 62 /24s RIPE AS Blocks 1877-1901, 2043, 2047, 2107-2136, 2585-2614 (pre-ERX allocations) 2773-2822, 2830-2879, 3154-3353, 5377-5631 6656-6911, 8192-9215, 12288-13311, 15360-16383 20480-21503, 24576-25599, 28672-29695 30720-31743, 33792-35839, 38912-39935 40960-45055, 47104-52223, 56320-58367 59392-61439, 61952-62463, 64396-64495 196608-216475 RIPE Address Blocks 2/8, 5/8, 25/8, 31/8, 37/8, 46/8, 51/8, 53/8, 57/8, 62/8, 77/8, 78/8, 79/8, 80/8, 81/8, 82/8, 83/8, 84/8, 85/8, 86/8, 87/8, 88/8, 89/8, 90/8, 91/8, 92/8, 93/8, 94/8, 95/8, 109/8, 141/8, 145/8, 151/8, 176/8, 178/8, 185/8, 188/8, 193/8, 194/8, 195/8, 212/8, 213/8, 217/8, LACNIC Region Analysis Summary ------------------------------ Prefixes being announced by LACNIC Region ASes: 1231 Total LACNIC prefixes after maximum aggregation: 463 LACNIC Deaggregation factor: 2.66 Prefixes being announced from the LACNIC address blocks: 1230 Unique aggregates announced from the LACNIC address blocks: 633 LACNIC Region origin ASes present in the Internet Routing Table: 117 LACNIC Prefixes per ASN: 10.51 LACNIC Region origin ASes announcing only one prefix: 46 LACNIC Region transit ASes present in the Internet Routing Table: 22 Average LACNIC Region AS path length visible: 4.4 Max LACNIC Region AS path length visible: 12 Number of LACNIC region 32-bit ASNs visible in the Routing Table: 52 Number of LACNIC addresses announced to Internet: 3858176 Equivalent to 0 /8s, 58 /16s and 223 /24s LACNIC AS Blocks 26592-26623, 27648-28671, 52224-53247, 61440-61951, 64099-64197, 262144-274844 + ERX transfers LACNIC Address Blocks 177/8, 179/8, 181/8, 186/8, 187/8, 189/8, 190/8, 191/8, 200/8, 201/8, AfriNIC Region Analysis Summary ------------------------------- Prefixes being announced by AfriNIC Region ASes: 1216 Total AfriNIC prefixes after maximum aggregation: 202 AfriNIC Deaggregation factor: 6.02 Prefixes being announced from the AfriNIC address blocks: 1215 Unique aggregates announced from the AfriNIC address blocks: 284 AfriNIC Region origin ASes present in the Internet Routing Table: 50 AfriNIC Prefixes per ASN: 24.30 AfriNIC Region origin ASes announcing only one prefix: 28 AfriNIC Region transit ASes present in the Internet Routing Table: 11 Average AfriNIC Region AS path length visible: 4.8 Max AfriNIC Region AS path length visible: 9 Number of AfriNIC region 32-bit ASNs visible in the Routing Table: 28 Number of AfriNIC addresses announced to Internet: 2489856 Equivalent to 0 /8s, 37 /16s and 254 /24s AfriNIC AS Blocks 36864-37887, 327680-329727 & ERX transfers AfriNIC Address Blocks 41/8, 102/8, 105/8, 154/8, 196/8, 197/8, APNIC Region per AS prefix count summary ---------------------------------------- ASN No of nets /20 equiv MaxAgg Description 2907 584 2166 455 SINET-AS Research Organization of Informa 7497 453 180 23 CSTNET-AS-AP Computer Network Information 1237 196 72 151 KREONET-AS-KR KISTI, KR 58647 182 18 2 KAGAWAU-AS Kagawa University, JP 4538 166 2403 80 ERX-CERNET-BKB China Education and Resear 7575 161 281 108 AARNET-AS-AP Australian Academic and Rese 55824 150 19 20 NKN-CORE-NW NKN Core Network, IN 4762 75 4 1 MAHIDOL-BORDER-AS Mahidol University, Tha 6262 63 134 56 CSIRO Commonwealth Scientific and Industr 1659 57 458 32 ERX-TANET-ASN1 Taiwan Academic Network TA Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet-APNIC ARIN Region per AS prefix count summary --------------------------------------- ASN No of nets /20 equiv MaxAgg Description 2152 660 492 100 CENIC-2152, US 2920 229 44 49 LACOE, US 376 200 162 150 RISQ-AS, CA 5786 198 16 1 UPRENET, PR 18558 139 18 5 NETBLK-RCOEK, US 81 114 455 35 NCREN, US 21976 88 34 14 NJEDGE-NET, US 237 84 542 49 MERIT-AS-14, US 1736 79 16 1 MU-AS, US 3477 79 79 37 NOAA-NWAVE, US Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet-ARIN RIPE Region per AS prefix count summary --------------------------------------- ASN No of nets /20 equiv MaxAgg Description 680 282 1883 249 DFN Verein zur Foerderung eines Deutschen 786 209 1738 187 JANET Jisc Services Limited, GB 559 115 533 105 SWITCH Switch, Swiss Academic and Researc 8895 102 24 5 ISU Internet Services Unit ISU, SA 1103 98 1247 83 SURFNET-NL SURFnet, The Netherlands, NL 2614 88 26 68 ROEDUNET, RO 137 82 677 77 ASGARR Consortium GARR, IT 1930 77 88 72 RCCN Fundacao para a Ciencia e a Tecnolog 553 75 366 75 BELWUE BelWue-Koordination, DE 2200 65 630 60 FR-RENATER Reseau National de telecommuni Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet-RIPE LACNIC Region per AS prefix count summary ----------------------------------------- ASN No of nets /20 equiv MaxAgg Description 1916 205 177 41 Rede Nacional de Ensino e Pesquisa, BR 28391 160 10 72 Universidad Juarez Autonoma de Tabasco, M 11340 111 25 50 Red Universitaria Nacional, CL 271640 68 8 1 UNIVERSIDADE FEDERAL DE VICOSA, BR 3596 66 8 4 Universidad Autonoma Metropolitana, MX 19611 53 17 2 Associacao Antonio Vieira - Unisinos, BR 61468 51 3 21 CEDIA, EC 2715 49 84 36 Fundacao Carlos Chagas Filho de Amparo a 1251 42 35 27 FUNDACAO DE AMPARO A PESQUISA DO ESTADO S 28614 38 2 2 Fundacao Universidade Regional de Blumena Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet-LACNIC AfriNIC Region per AS prefix count summary ------------------------------------------ ASN No of nets /20 equiv MaxAgg Description 36914 555 82 3 KENET-AS, KE 2018 375 318 69 TENET-1, ZA 2561 68 4 34 EUN, EG 8094 47 48 18 PUKNET, ZA 37215 44 8 1 MAREN, MW 6879 24 2 9 ENSTINET-, EG 37501 11 49 6 UOFS, ZA 327700 11 16 1 MoRENet, MZ 37654 10 1 6 RwEdNet-AS, RW 36982 8 33 8 UCT, ZA Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet-AFRINIC Global Per AS prefix count summary ---------------------------------- ASN No of nets /20 equiv MaxAgg Description 2152 660 492 100 CENIC-2152, US 2907 584 2166 455 SINET-AS Research Organization of Informa 36914 555 82 3 KENET-AS, KE 7497 453 180 23 CSTNET-AS-AP Computer Network Information 2018 375 318 69 TENET-1, ZA 680 282 1883 249 DFN Verein zur Foerderung eines Deutschen 2920 229 44 49 LACOE, US 786 209 1738 187 JANET Jisc Services Limited, GB 1916 205 177 41 Rede Nacional de Ensino e Pesquisa, BR 376 200 162 150 RISQ-AS, CA Complete listing at https://bgp.nsrc.org/REN/ESnet/data-ASnet Global Per AS Maximum Aggregation summary ----------------------------------------- ASN No of nets Net Savings Description 36914 555 552 KENET-AS, KE 7497 453 430 CSTNET-AS-AP Computer Network Information Cente 2018 375 306 TENET-1, ZA 5786 198 197 UPRENET, PR 2920 229 180 LACOE, US 58647 182 180 KAGAWAU-AS Kagawa University, JP 1916 205 164 Rede Nacional de Ensino e Pesquisa, BR 18558 139 134 NETBLK-RCOEK, US 55824 150 130 NKN-CORE-NW NKN Core Network, IN 2907 584 129 SINET-AS Research Organization of Information a Complete listing at https://bgp.nsrc.org/REN/ESnet/data-CIDRnet List of Unregistered Origin ASNs (Global) ----------------------------------------- Bad AS Designation Net Originated Transit AS Transit AS Name 26971 UNALLOCATED 129.111.0.0/16 276 OTS-AS-276, US 64011 UNALLOCATED 130.215.0.0/16 10326 WPI, US 396334 UNALLOCATED 205.143.136.0/21 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.136.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.137.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.138.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.139.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.140.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.141.0/24 5078 ONENET-AS-1, US 396334 UNALLOCATED 205.143.142.0/24 5078 ONENET-AS-1, US Complete listing at https://bgp.nsrc.org/REN/ESnet/data-badAS Advertised Unallocated Addresses -------------------------------- Unassigned Network ASN Information AS Name 162.212.34.0/24 Origin: 54048 CVIN, US 162.212.34.0/24 Transit: 2152 CENIC-2152, US 164.160.192.0/21 Origin: 37661 NRaE1-AS, NG 164.160.192.0/21 Transit: 37288 WACREN, SN 203.9.156.0/24 Origin: 1851 ADELAIDE-UNIVERSITY-AS-AP Adelaide Unive 203.9.156.0/24 Transit: 7575 AARNET-AS-AP Australian Academic and Res Complete listing at https://bgp.nsrc.org/REN/ESnet/data-add-IANA Number of prefixes announced per prefix length (Global) ------------------------------------------------------- /1:0 /2:0 /3:0 /4:0 /5:0 /6:0 /7:0 /8:0 /9:0 /10:0 /11:0 /12:0 /13:0 /14:33 /15:114 /16:1916 /17:415 /18:445 /19:580 /20:827 /21:858 /22:1423 /23:1564 /24:10715 /25:0 /26:0 /27:0 /28:0 /29:0 /30:0 /31:0 /32:0 Advertised prefixes smaller than registry allocations ----------------------------------------------------- ASN No of nets Total ann. Description 36914 531 555 KENET-AS, KE 8895 99 102 ISU Internet Services Unit ISU, SA 2152 73 660 CENIC-2152, US 31638 48 48 ASN-LEPIDA, IT 37215 38 44 MAREN, MW 200521 34 58 SEAP-AGE, ES 28614 32 38 Fundacao Universidade Regional de Blumenau, BR 46115 32 35 LUTHER, US 25977 30 44 HCCS, US 27609 29 45 USC-UNIVERSITY-HOSPITAL, US Complete listing at https://bgp.nsrc.org/REN/ESnet/data-sXXas-nos Number of /24s announced per /8 block (Global) ---------------------------------------------- 1:2 5:16 8:2 12:1 14:94 18:39 23:9 24:3 31:1 35:5 37:26 38:13 40:1 41:224 42:17 44:5 45:35 46:4 47:1 49:13 50:5 52:1 58:14 59:20 60:6 61:3 62:4 63:32 64:49 65:21 66:57 67:43 68:18 69:19 70:2 71:1 72:6 74:54 76:28 77:7 78:3 79:9 80:6 81:27 82:3 83:6 84:5 85:26 86:1 87:1 89:16 91:37 93:13 94:2 95:2 96:5 97:1 98:2 101:3 102:7 103:342 104:74 108:8 109:10 111:7 113:2 114:21 116:7 117:5 118:32 119:30 121:17 122:8 123:8 124:42 125:3 128:58 129:45 130:99 131:62 132:64 133:157 134:114 136:199 137:115 138:9 139:4 140:33 141:9 142:30 143:26 144:45 145:3 146:137 147:66 148:232 149:11 150:36 151:10 152:113 153:14 154:38 155:86 156:127 157:23 158:28 159:118 160:32 161:31 162:29 163:66 164:9 165:43 166:1 167:27 168:103 169:6 170:19 171:1 172:1 173:6 174:1 175:15 177:5 179:12 180:16 182:11 184:10 185:43 186:3 187:23 188:20 190:16 191:13 192:1398 193:291 194:94 195:87 196:148 197:345 198:552 199:250 200:295 201:20 202:585 203:431 204:408 205:183 206:200 207:349 208:38 209:149 210:222 211:4 212:137 213:4 216:88 217:22 218:19 219:5 220:16 222:4 223:6 End of report