IPv4 R&E Routing Table Report 22:20 GMT Wed 29 Apr, 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: 18926 Prefixes after maximum aggregation (per Origin AS): 10329 Deaggregation factor: 1.83 Unique aggregates announced (without unneeded subnets): 11493 Number of IPv4 prefixes with a valid ROA: 8298 Number of IPv4 prefixes with an invalid ROA: 1 Number of IPv4 prefixes with no ROA: 10627 Total ASes present in the Internet Routing Table: 2643 Prefixes per ASN: 7.16 Origin-only ASes present in the Internet Routing Table: 2302 Origin ASes announcing only one prefix: 1006 Transit ASes present in the Internet Routing Table: 341 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: 3 Number of instances of unregistered ASNs: 3 Number of 32-bit ASNs allocated by the RIRs: 49533 Number of 32-bit ASNs visible in the Routing Table: 670 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: 1 Number of addresses announced to Internet: 166658048 Equivalent to 9 /8s, 239 /16s and 0 /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: 2167 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 4585 Total APNIC prefixes after maximum aggregation: 2256 APNIC Deaggregation factor: 2.03 Prefixes being announced from the APNIC address blocks: 4584 Unique aggregates announced from the APNIC address blocks: 2516 APNIC Region origin ASes present in the Internet Routing Table: 570 APNIC Prefixes per ASN: 8.04 APNIC Region origin ASes announcing only one prefix: 238 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: 229 Number of APNIC addresses announced to Internet: 35777536 Equivalent to 2 /8s, 33 /16s and 236 /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: 8600 Total ARIN prefixes after maximum aggregation: 4752 ARIN Deaggregation factor: 1.81 Prefixes being announced from the ARIN address blocks: 8614 Unique aggregates announced from the ARIN address blocks: 5333 ARIN Region origin ASes present in the Internet Routing Table: 1276 ARIN Prefixes per ASN: 6.75 ARIN Region origin ASes announcing only one prefix: 440 ARIN Region transit ASes present in the Internet Routing Table: 151 Average ARIN Region AS path length visible: 4.1 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: 71836160 Equivalent to 4 /8s, 72 /16s and 34 /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, 393216-404380 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: 3326 Total RIPE prefixes after maximum aggregation: 2663 RIPE Deaggregation factor: 1.25 Prefixes being announced from the RIPE address blocks: 3316 Unique aggregates announced from the RIPE address blocks: 2739 RIPE Region origin ASes present in the Internet Routing Table: 594 RIPE Prefixes per ASN: 5.58 RIPE Region origin ASes announcing only one prefix: 270 RIPE Region transit ASes present in the Internet Routing Table: 98 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: 52741888 Equivalent to 3 /8s, 36 /16s and 199 /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: 1211 Total LACNIC prefixes after maximum aggregation: 464 LACNIC Deaggregation factor: 2.61 Prefixes being announced from the LACNIC address blocks: 1210 Unique aggregates announced from the LACNIC address blocks: 633 LACNIC Region origin ASes present in the Internet Routing Table: 117 LACNIC Prefixes per ASN: 10.34 LACNIC Region origin ASes announcing only one prefix: 43 LACNIC Region transit ASes present in the Internet Routing Table: 23 Average LACNIC Region AS path length visible: 4.5 Max LACNIC Region AS path length visible: 12 Number of LACNIC region 32-bit ASNs visible in the Routing Table: 51 Number of LACNIC addresses announced to Internet: 3850240 Equivalent to 0 /8s, 58 /16s and 192 /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: 1201 Total AfriNIC prefixes after maximum aggregation: 191 AfriNIC Deaggregation factor: 6.29 Prefixes being announced from the AfriNIC address blocks: 1201 Unique aggregates announced from the AfriNIC address blocks: 271 AfriNIC Region origin ASes present in the Internet Routing Table: 37 AfriNIC Prefixes per ASN: 32.46 AfriNIC Region origin ASes announcing only one prefix: 15 AfriNIC Region transit ASes present in the Internet Routing Table: 9 Average AfriNIC Region AS path length visible: 5.1 Max AfriNIC Region AS path length visible: 10 Number of AfriNIC region 32-bit ASNs visible in the Routing Table: 16 Number of AfriNIC addresses announced to Internet: 2451968 Equivalent to 0 /8s, 37 /16s and 106 /24s AfriNIC AS Blocks 36864-37887, 327680-330751 & 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 2152 459 SINET-AS Research Organization of Informa 7497 459 212 24 CSTNET-AS-AP Computer Network Information 1237 195 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 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 686 492 98 CENIC-2152 - CENIC, US 2920 226 44 49 LACOE - Los Angeles County Office of Educ 5786 197 16 1 UPRENET - University of Puerto Rico, PR 376 196 162 150 RISQ-AS - Reseau dInformations Scientifiq 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 3477 84 79 42 NOAA-NWAVE - National Oceanic and Atmosph 237 83 542 49 MERIT-AS-14 - Merit Network Inc., US 1736 79 16 1 MU-AS - Marquette University, 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 680 291 1883 253 DFN Verein zur Foerderung eines Deutschen 786 211 1710 188 JANET Jisc Services Limited, GB 559 115 533 105 SWITCH Switch, Swiss Academic and Researc 8895 100 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 219 161 40 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 65 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 554 82 3 KENET-AS, KE 2018 372 318 69 TENET-1, ZA 2561 68 4 34 EUN, EG 8094 46 48 21 PUKNET, ZA 37215 45 8 1 MAREN, MW 6879 24 2 9 ENSTINET-, EG 37501 11 49 6 UOFS, ZA 37182 10 8 1 TERNET, TZ 327700 10 16 1 MoRENet, MZ 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 686 492 98 CENIC-2152 - CENIC, US 2907 598 2152 459 SINET-AS Research Organization of Informa 36914 554 82 3 KENET-AS, KE 7497 459 212 24 CSTNET-AS-AP Computer Network Information 2018 372 318 69 TENET-1, ZA 680 291 1883 253 DFN Verein zur Foerderung eines Deutschen 2920 226 44 49 LACOE - Los Angeles County Office of Educ 1916 219 161 40 Rede Nacional de Ensino e Pesquisa, BR 786 211 1710 188 JANET Jisc Services Limited, GB 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 554 551 KENET-AS, KE 7497 459 435 CSTNET-AS-AP Computer Network Information Cente 2018 372 303 TENET-1, ZA 5786 197 196 UPRENET - University of Puerto Rico, PR 58647 182 180 KAGAWAU-AS Kagawa University, JP 1916 219 179 Rede Nacional de Ensino e Pesquisa, BR 2920 226 177 LACOE - Los Angeles County Office of Education, 2907 598 139 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 22272 UNALLOCATED 206.208.24.0/21 6325 ILLINOIS-CENTURY - Illi 401367 UNALLOCATED 216.186.25.0/24 10430 WA-K20 - Washington Sta Complete listing at https://bgp.nsrc.org/REN/ESnet/data-badAS Advertised Unallocated Addresses -------------------------------- Unassigned Network ASN Information AS Name 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 /16:1900 /17:414 /18:453 /19:597 /20:828 /21:856 /22:1413 /23:1576 /24:10742 /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 530 554 KENET-AS, KE 8895 97 100 ISU Internet Services Unit ISU, SA 2152 84 686 CENIC-2152 - CENIC, US 31638 48 48 ASN-LEPIDA, IT 37215 39 45 MAREN, MW 200521 33 57 SEAP-AGE, ES 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 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 14:96 18:39 23:10 24:2 31:1 35:3 37:26 38:14 40:1 41:234 42:17 44:5 45:30 46:5 47:1 49:13 50:6 58:14 59:20 60:6 61:3 62:4 63:32 64:46 65:21 66:54 67:43 68:18 69:19 70:2 72:6 74:56 76:28 77:4 78:3 79:5 80:6 81:27 82:3 83:7 84:4 85:26 86:1 87:1 89:17 91:37 93:14 94:2 95:2 96:5 97:1 98:2 101:3 102:2 103:332 104:75 108:9 109:9 111:7 113:2 114:24 116:7 117:5 118:32 119:27 121:17 122:8 123:8 124:42 125:3 128:58 129:48 130:101 131:55 132:63 133:156 134:115 136:199 137:121 138:9 139:4 140:33 141:6 142:31 143:27 144:10 145:13 146:135 147:66 148:233 149:11 150:36 151:11 152:114 153:15 154:36 155:87 156:123 157:27 158:28 159:114 160:34 161:35 162:28 163:78 164:10 165:46 166:2 167:33 168:104 169:7 170:18 171:1 172:1 173:6 174:1 175:15 177:7 179:12 180:16 182:11 184:1 185:41 186:3 187:7 188:22 190:16 191:13 192:1419 193:290 194:101 195:87 196:148 197:342 198:571 199:249 200:310 201:5 202:591 203:408 204:415 205:179 206:202 207:354 208:36 209:165 210:226 211:6 212:136 213:4 216:95 217:22 218:19 219:6 220:16 222:4 223:6 End of report