IPv4 R&E Routing Table Report 22:20 GMT Sat 28 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: 18777 Prefixes after maximum aggregation (per Origin AS): 10218 Deaggregation factor: 1.84 Unique aggregates announced (without unneeded subnets): 11346 Number of IPv4 prefixes with a valid ROA: 8146 Number of IPv4 prefixes with an invalid ROA: 1 Number of IPv4 prefixes with no ROA: 10630 Total ASes present in the Internet Routing Table: 2641 Prefixes per ASN: 7.11 Origin-only ASes present in the Internet Routing Table: 2295 Origin ASes announcing only one prefix: 1024 Transit ASes present in the Internet Routing Table: 346 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: 48897 Number of 32-bit ASNs visible in the Routing Table: 676 Prefixes from 32-bit ASNs in the Routing Table: 1874 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: 166498816 Equivalent to 9 /8s, 236 /16s and 146 /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: 2137 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 4576 Total APNIC prefixes after maximum aggregation: 2251 APNIC Deaggregation factor: 2.03 Prefixes being announced from the APNIC address blocks: 4575 Unique aggregates announced from the APNIC address blocks: 2513 APNIC Region origin ASes present in the Internet Routing Table: 568 APNIC Prefixes per ASN: 8.05 APNIC Region origin ASes announcing only one prefix: 239 APNIC Region transit ASes present in the Internet Routing Table: 49 Average APNIC Region AS path length visible: 3.8 Max APNIC Region AS path length visible: 12 Number of APNIC region 32-bit ASNs visible in the Routing Table: 228 Number of APNIC addresses announced to Internet: 35647744 Equivalent to 2 /8s, 31 /16s and 241 /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: 8461 Total ARIN prefixes after maximum aggregation: 4638 ARIN Deaggregation factor: 1.82 Prefixes being announced from the ARIN address blocks: 8483 Unique aggregates announced from the ARIN address blocks: 5175 ARIN Region origin ASes present in the Internet Routing Table: 1263 ARIN Prefixes per ASN: 6.72 ARIN Region origin ASes announcing only one prefix: 444 ARIN Region transit ASes present in the Internet Routing Table: 154 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: 71689216 Equivalent to 4 /8s, 69 /16s and 228 /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: 3344 Total RIPE prefixes after maximum aggregation: 2671 RIPE Deaggregation factor: 1.25 Prefixes being announced from the RIPE address blocks: 3330 Unique aggregates announced from the RIPE address blocks: 2750 RIPE Region origin ASes present in the Internet Routing Table: 603 RIPE Prefixes per ASN: 5.52 RIPE Region origin ASes announcing only one prefix: 276 RIPE Region transit ASes present in the Internet Routing Table: 101 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: 152 Number of RIPE addresses announced to Internet: 52847360 Equivalent to 3 /8s, 38 /16s and 99 /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: 1181 Total LACNIC prefixes after maximum aggregation: 456 LACNIC Deaggregation factor: 2.59 Prefixes being announced from the LACNIC address blocks: 1180 Unique aggregates announced from the LACNIC address blocks: 626 LACNIC Region origin ASes present in the Internet Routing Table: 115 LACNIC Prefixes per ASN: 10.26 LACNIC Region origin ASes announcing only one prefix: 45 LACNIC Region transit ASes present in the Internet Routing Table: 21 Average LACNIC Region AS path length visible: 4.4 Max LACNIC Region AS path length visible: 9 Number of LACNIC region 32-bit ASNs visible in the Routing Table: 50 Number of LACNIC addresses announced to Internet: 3847680 Equivalent to 0 /8s, 58 /16s and 182 /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: 1203 Total AfriNIC prefixes after maximum aggregation: 198 AfriNIC Deaggregation factor: 6.08 Prefixes being announced from the AfriNIC address blocks: 1206 Unique aggregates announced from the AfriNIC address blocks: 279 AfriNIC Region origin ASes present in the Internet Routing Table: 42 AfriNIC Prefixes per ASN: 28.71 AfriNIC Region origin ASes announcing only one prefix: 20 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: 2464256 Equivalent to 0 /8s, 37 /16s and 154 /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 458 SINET-AS Research Organization of Informa 7497 454 180 23 CSTNET-AS-AP Computer Network Information 1237 199 72 153 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 163 281 110 AARNET-AS-AP Australian Academic and Rese 55824 153 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 681 492 98 CENIC-2152 - CENIC, US 2920 227 44 49 LACOE - Los Angeles County Office of Educ 376 197 162 151 RISQ-AS - Reseau dInformations Scientifiq 5786 190 16 1 UPRENET - University of Puerto Rico, PR 18558 141 18 5 NETBLK-RCOEK - Riverside County Office of 81 115 455 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 786 209 1731 188 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 204 177 41 Rede Nacional de Ensino e Pesquisa, BR 28391 161 10 72 Universidad Juarez Autonoma de Tabasco, M 11340 110 25 49 Red Universitaria Nacional, CL 3596 66 8 4 Universidad Autonoma Metropolitana, MX 271640 66 8 1 UNIVERSIDADE FEDERAL DE VICOSA, BR 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 37 31 26 FUNDACAO DE AMPARO A PESQUISA DO ESTADO S 21612 27 16 1 FUNDACAO INSTITUTO OSWALDO CRUZ, BR 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 542 82 3 KENET-AS, KE 2018 375 318 69 TENET-1, ZA 2561 68 4 34 EUN, EG 8094 46 48 21 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 37182 10 8 1 TERNET, TZ 37654 9 1 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 681 492 98 CENIC-2152 - CENIC, US 2907 598 2168 458 SINET-AS Research Organization of Informa 36914 542 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 227 44 49 LACOE - Los Angeles County Office of Educ 786 209 1731 188 JANET Jisc Services Limited, GB 1916 204 177 41 Rede Nacional de Ensino e Pesquisa, BR 1237 199 72 153 KREONET-AS-KR KISTI, KR 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 542 539 KENET-AS, KE 7497 454 431 CSTNET-AS-AP Computer Network Information Cente 2018 375 306 TENET-1, ZA 5786 190 189 UPRENET - University of Puerto Rico, PR 58647 182 180 KAGAWAU-AS Kagawa University, JP 2920 227 178 LACOE - Los Angeles County Office of Education, 1916 204 163 Rede Nacional de Ensino e Pesquisa, BR 2907 598 140 SINET-AS Research Organization of Information a 18558 141 136 NETBLK-RCOEK - Riverside County Office of Educa 55824 153 132 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 /16:1905 /17:413 /18:442 /19:593 /20:818 /21:849 /22:1392 /23:1559 /24:10660 /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 518 542 KENET-AS, KE 8895 100 103 ISU Internet Services Unit ISU, SA 2152 77 681 CENIC-2152 - CENIC, US 31638 48 48 ASN-LEPIDA, IT 37215 38 44 MAREN, MW 46115 32 35 LUTHER - Luther College, US 200521 32 54 SEAP-AGE, ES 25977 30 44 HCCS - HOUSTON COMMUNITY COLLEGE SYSTEM, US 27609 29 45 USC-UNIVERSITY-HOSPITAL - USC-University Hospital, US 40326 29 33 ECKERD-COLLEGE - Eckerd College, 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 41:228 42:16 44:5 45:34 46:4 47:1 49:13 50:5 58:14 59:20 60:6 61:3 62:4 63:32 64:47 65:21 66:56 67:44 68:18 69:18 70:2 72:6 74:55 76:37 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 98:2 101:3 102:4 103:338 104:75 108:8 109:8 111:3 113:2 114:24 116:7 117:5 118:32 119:23 121:16 122:8 123:8 124:42 125:3 128:57 129:46 130:103 131:65 132:64 133:156 134:112 136:193 137:120 138:9 139:5 140:33 141:4 142:29 143:27 144:10 145:13 146:135 147:66 148:234 149:11 150:36 151:11 152:114 153:15 154:40 155:86 156:124 157:26 158:25 159:118 160:33 161:34 162:28 163:76 164:9 165:43 166:2 167:27 168:103 169:7 170:19 171:1 172:1 173:6 174:1 175:15 177:6 179:12 180:16 182:11 184:1 185:41 186:3 187:7 188:22 190:16 191:13 192:1408 193:300 194:97 195:89 196:149 197:339 198:554 199:248 200:289 201:5 202:577 203:428 204:411 205:182 206:196 207:351 208:36 209:151 210:222 211:5 212:138 213:4 216:86 217:22 218:19 219:6 220:16 222:4 223:6 End of report