IPv4 R&E Routing Table Report 22:20 GMT Mon 02 Feb, 2026 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: 18691 Prefixes after maximum aggregation (per Origin AS): 10121 Deaggregation factor: 1.85 Unique aggregates announced (without unneeded subnets): 11241 Number of IPv4 prefixes with a valid ROA: 8003 Number of IPv4 prefixes with an invalid ROA: 1 Number of IPv4 prefixes with no ROA: 10687 Total ASes present in the Internet Routing Table: 2604 Prefixes per ASN: 7.18 Origin-only ASes present in the Internet Routing Table: 2259 Origin ASes announcing only one prefix: 1011 Transit ASes present in the Internet Routing Table: 345 Transit-only ASes present in the Internet Routing Table: 46 Paths with bogon ASNs present in the IPv4 Routing Table: 0 Average AS path length visible in the Internet Routing Table: 4.0 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: 48552 Number of 32-bit ASNs visible in the Routing Table: 646 Prefixes from 32-bit ASNs in the Routing Table: 1813 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: 166637056 Equivalent to 9 /8s, 238 /16s and 174 /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: 2194 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 4465 Total APNIC prefixes after maximum aggregation: 2193 APNIC Deaggregation factor: 2.04 Prefixes being announced from the APNIC address blocks: 4464 Unique aggregates announced from the APNIC address blocks: 2432 APNIC Region origin ASes present in the Internet Routing Table: 530 APNIC Prefixes per ASN: 8.42 APNIC Region origin ASes announcing only one prefix: 227 APNIC Region transit ASes present in the Internet Routing Table: 49 Average APNIC Region AS path length visible: 3.7 Max APNIC Region AS path length visible: 13 Number of APNIC region 32-bit ASNs visible in the Routing Table: 197 Number of APNIC addresses announced to Internet: 35612160 Equivalent to 2 /8s, 31 /16s and 102 /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: 8415 Total ARIN prefixes after maximum aggregation: 4611 ARIN Deaggregation factor: 1.82 Prefixes being announced from the ARIN address blocks: 8437 Unique aggregates announced from the ARIN address blocks: 5151 ARIN Region origin ASes present in the Internet Routing Table: 1265 ARIN Prefixes per ASN: 6.67 ARIN Region origin ASes announcing only one prefix: 445 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: 226 Number of ARIN addresses announced to Internet: 71857920 Equivalent to 4 /8s, 72 /16s and 119 /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: 3354 Total RIPE prefixes after maximum aggregation: 2660 RIPE Deaggregation factor: 1.26 Prefixes being announced from the RIPE address blocks: 3344 Unique aggregates announced from the RIPE address blocks: 2751 RIPE Region origin ASes present in the Internet Routing Table: 601 RIPE Prefixes per ASN: 5.56 RIPE Region origin ASes announcing only one prefix: 275 RIPE Region transit ASes present in the Internet Routing Table: 100 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: 151 Number of RIPE addresses announced to Internet: 52914432 Equivalent to 3 /8s, 39 /16s and 105 /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: 1222 Total LACNIC prefixes after maximum aggregation: 458 LACNIC Deaggregation factor: 2.67 Prefixes being announced from the LACNIC address blocks: 1221 Unique aggregates announced from the LACNIC address blocks: 628 LACNIC Region origin ASes present in the Internet Routing Table: 116 LACNIC Prefixes per ASN: 10.53 LACNIC Region origin ASes announcing only one prefix: 45 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: 3777792 Equivalent to 0 /8s, 57 /16s and 165 /24s LACNIC AS Blocks 26592-26623, 27648-28671, 52224-53247, 61440-61951, 64099-64197, 262144-275868 + 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: 1223 Total AfriNIC prefixes after maximum aggregation: 195 AfriNIC Deaggregation factor: 6.27 Prefixes being announced from the AfriNIC address blocks: 1222 Unique aggregates announced from the AfriNIC address blocks: 276 AfriNIC Region origin ASes present in the Internet Routing Table: 42 AfriNIC Prefixes per ASN: 29.10 AfriNIC Region origin ASes announcing only one prefix: 19 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: 20 Number of AfriNIC addresses announced to Internet: 2472192 Equivalent to 0 /8s, 37 /16s and 185 /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 598 2168 460 SINET-AS Research Organization of Informa 7497 454 180 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 165 2403 80 ERX-CERNET-BKB China Education and Resear 7575 161 281 108 AARNET-AS-AP Australian Academic and Rese 55824 152 19 21 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 678 492 98 CENIC-2152 - CENIC, US 2920 229 44 49 LACOE - Los Angeles County Office of Educ 5786 197 16 1 UPRENET - University of Puerto Rico, PR 376 196 162 151 RISQ-AS - Reseau dInformations Scientifiq 18558 141 18 5 NETBLK-RCOEK - Riverside County Office of 81 117 455 35 NCREN - MCNC, US 21976 92 34 14 NJEDGE-NET - NJEDge.Net, Inc., US 237 83 542 49 MERIT-AS-14 - Merit Network Inc., US 1736 79 16 1 MU-AS - Marquette University, US 3477 78 79 37 NOAA-NWAVE - National Oceanic and Atmosph 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 680 291 1883 253 DFN Verein zur Foerderung eines Deutschen 786 210 1735 186 JANET Jisc Services Limited, GB 559 115 533 105 SWITCH Switch, Swiss Academic and Researc 8895 103 24 5 ISU Internet Services Unit ISU, SA 1103 98 1247 83 SURFNET-NL SURFnet, The Netherlands, NL 2614 87 26 67 ROEDUNET, RO 137 82 677 77 ASGARR Consortium GARR, IT 1930 78 88 73 RCCN Fundacao para a Ciencia e a Tecnolog 553 75 366 75 BELWUE BelWue-Koordination, DE 2200 64 630 59 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 161 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 28614 38 2 2 Fundacao Universidade Regional de Blumena 1251 37 31 26 FUNDACAO DE AMPARO A PESQUISA DO ESTADO S 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 570 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 327700 14 16 1 MoRENet, MZ 37501 11 49 6 UOFS, ZA 36982 8 33 8 UCT, ZA 37654 7 0 5 RwEdNet-AS, RW 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 678 492 98 CENIC-2152 - CENIC, US 2907 598 2168 460 SINET-AS Research Organization of Informa 36914 570 82 3 KENET-AS, KE 7497 454 180 23 CSTNET-AS-AP Computer Network Information 2018 375 318 69 TENET-1, ZA 680 291 1883 253 DFN Verein zur Foerderung eines Deutschen 2920 229 44 49 LACOE - Los Angeles County Office of Educ 786 210 1735 186 JANET Jisc Services Limited, GB 1916 205 177 41 Rede Nacional de Ensino e Pesquisa, BR 5786 197 16 1 UPRENET - University of Puerto Rico, PR 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 570 567 KENET-AS, KE 7497 454 431 CSTNET-AS-AP Computer Network Information Cente 2018 375 306 TENET-1, ZA 5786 197 196 UPRENET - University of Puerto Rico, PR 2920 229 180 LACOE - Los Angeles County Office of Education, 58647 182 180 KAGAWAU-AS Kagawa University, JP 1916 205 164 Rede Nacional de Ensino e Pesquisa, BR 2907 598 138 SINET-AS Research Organization of Information a 18558 141 136 NETBLK-RCOEK - Riverside County Office of Educa 55824 152 131 NKN-CORE-NW NKN Core Network, IN 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 - University 64011 UNALLOCATED 130.215.0.0/16 10326 WPI - Worcester Polytec 396334 UNALLOCATED 205.143.136.0/21 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.136.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.137.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.138.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.139.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.140.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.141.0/24 5078 ONENET-AS-1 - Oklahoma 396334 UNALLOCATED 205.143.142.0/24 5078 ONENET-AS-1 - Oklahoma 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 - Vast Networks, US 162.212.34.0/24 Transit: 2152 CENIC-2152 - CENIC, 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 /15:113 /16:1908 /17:414 /18:445 /19:591 /20:817 /21:850 /22:1367 /23:1536 /24:10617 /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 546 570 KENET-AS, KE 8895 100 103 ISU Internet Services Unit ISU, SA 2152 77 678 CENIC-2152 - CENIC, US 31638 48 48 ASN-LEPIDA, IT 37215 38 44 MAREN, MW 200521 34 59 SEAP-AGE, ES 28614 32 38 Fundacao Universidade Regional de Blumenau, BR 46115 32 35 LUTHER - Luther College, US 25977 30 44 HCCS - HOUSTON COMMUNITY COLLEGE SYSTEM, US 27609 29 45 USC-UNIVERSITY-HOSPITAL - 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 5:18 8:2 12:1 14:95 18:39 23:9 24:2 31:1 35:3 37:26 38:13 40:1 41:233 42:16 44:5 45:30 46:4 47:1 49:13 50:4 58:14 59:20 60:6 61:3 62:8 63:32 64:49 65:21 66:60 67:43 68:18 69:19 70:2 72:6 74:55 76:28 77:7 78:3 79:9 80:6 81:27 82:3 83:6 84:4 85:26 86:1 87:1 89:16 91:37 93:14 94:2 95:2 96:5 97:1 98:2 101:3 102:4 103:271 104:75 108:8 109:8 111:3 113:2 114:24 116:7 117:5 118:32 119:23 121:17 122:8 123:8 124:42 125:3 128:55 129:43 130:103 131:68 132:65 133:156 134:112 136:198 137:115 138:9 139:5 140:33 141:4 142:30 143:26 144:10 145:13 146:137 147:41 148:235 149:11 150:34 151:10 152:116 153:15 154:37 155:86 156:126 157:25 158:25 159:118 160:33 161:32 162:29 163:76 164:9 165:43 166:2 167:29 168:103 169:7 170:19 171:1 172:1 173:6 174:1 175:15 177:7 179:12 180:16 182:2 184:1 185:42 186:3 187:23 188:22 190:16 191:13 192:1414 193:297 194:101 195:86 196:149 197:354 198:554 199:251 200:292 201:20 202:581 203:419 204:411 205:183 206:195 207:349 208:36 209:152 210:224 211:4 212:139 213:4 216:89 217:22 218:19 219:5 220:16 222:4 223:6 End of report