IPv4 R&E Routing Table Report 22:05 GMT Mon 23 Mar, 2026 IPv4 BGP Table (R&E) as seen at CENIC. Report Website: https://bgp.nsrc.org/REN Detailed Analysis: https://bgp.nsrc.org/REN/CENIC/ Analysis Summary ---------------- BGP routing table entries examined: 20059 Prefixes after maximum aggregation (per Origin AS): 11621 Deaggregation factor: 1.73 Unique aggregates announced (without unneeded subnets): 12977 Number of IPv4 prefixes with a valid ROA: 9423 Number of IPv4 prefixes with an invalid ROA: 13 Number of IPv4 prefixes with no ROA: 10623 Total ASes present in the Internet Routing Table: 2763 Prefixes per ASN: 7.26 Origin-only ASes present in the Internet Routing Table: 2392 Origin ASes announcing only one prefix: 1067 Transit ASes present in the Internet Routing Table: 371 Transit-only ASes present in the Internet Routing Table: 59 Paths with bogon ASNs present in the IPv4 Routing Table: 5 Average AS path length visible in the Internet Routing Table: 4.0 Max AS path length visible: 15 Max AS path prepend of ASN (395156) 12 Prefixes from unregistered ASNs in the Routing Table: 6 Number of instances of unregistered ASNs: 6 Number of 32-bit ASNs allocated by the RIRs: 49057 Number of 32-bit ASNs visible in the Routing Table: 709 Prefixes from 32-bit ASNs in the Routing Table: 1953 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: 268841728 Equivalent to 16 /8s, 6 /16s and 51 /24s Percentage of available address space announced: 7.3 Percentage of allocated address space announced: 7.3 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: 2336 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 4814 Total APNIC prefixes after maximum aggregation: 2373 APNIC Deaggregation factor: 2.03 Prefixes being announced from the APNIC address blocks: 4910 Unique aggregates announced from the APNIC address blocks: 2714 APNIC Region origin ASes present in the Internet Routing Table: 612 APNIC Prefixes per ASN: 8.02 APNIC Region origin ASes announcing only one prefix: 263 APNIC Region transit ASes present in the Internet Routing Table: 53 Average APNIC Region AS path length visible: 4.1 Max APNIC Region AS path length visible: 12 Number of APNIC region 32-bit ASNs visible in the Routing Table: 253 Number of APNIC addresses announced to Internet: 47142400 Equivalent to 2 /8s, 207 /16s and 86 /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: 9457 Total ARIN prefixes after maximum aggregation: 5881 ARIN Deaggregation factor: 1.61 Prefixes being announced from the ARIN address blocks: 8984 Unique aggregates announced from the ARIN address blocks: 6183 ARIN Region origin ASes present in the Internet Routing Table: 1318 ARIN Prefixes per ASN: 6.82 ARIN Region origin ASes announcing only one prefix: 458 ARIN Region transit ASes present in the Internet Routing Table: 167 Average ARIN Region AS path length visible: 3.6 Max ARIN Region AS path length visible: 15 Number of ARIN region 32-bit ASNs visible in the Routing Table: 226 Number of ARIN addresses announced to Internet: 134934272 Equivalent to 8 /8s, 10 /16s and 239 /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: 3360 Total RIPE prefixes after maximum aggregation: 2682 RIPE Deaggregation factor: 1.25 Prefixes being announced from the RIPE address blocks: 3733 Unique aggregates announced from the RIPE address blocks: 3136 RIPE Region origin ASes present in the Internet Routing Table: 597 RIPE Prefixes per ASN: 6.25 RIPE Region origin ASes announcing only one prefix: 269 RIPE Region transit ASes present in the Internet Routing Table: 101 Average RIPE Region AS path length visible: 4.6 Max RIPE Region AS path length visible: 14 Number of RIPE region 32-bit ASNs visible in the Routing Table: 151 Number of RIPE addresses announced to Internet: 79712256 Equivalent to 4 /8s, 192 /16s and 80 /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: 1205 Total LACNIC prefixes after maximum aggregation: 479 LACNIC Deaggregation factor: 2.52 Prefixes being announced from the LACNIC address blocks: 1208 Unique aggregates announced from the LACNIC address blocks: 657 LACNIC Region origin ASes present in the Internet Routing Table: 131 LACNIC Prefixes per ASN: 9.22 LACNIC Region origin ASes announcing only one prefix: 58 LACNIC Region transit ASes present in the Internet Routing Table: 26 Average LACNIC Region AS path length visible: 5.0 Max LACNIC Region AS path length visible: 13 Number of LACNIC region 32-bit ASNs visible in the Routing Table: 59 Number of LACNIC addresses announced to Internet: 4454912 Equivalent to 0 /8s, 67 /16s and 250 /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: 1217 Total AfriNIC prefixes after maximum aggregation: 200 AfriNIC Deaggregation factor: 6.08 Prefixes being announced from the AfriNIC address blocks: 1221 Unique aggregates announced from the AfriNIC address blocks: 284 AfriNIC Region origin ASes present in the Internet Routing Table: 42 AfriNIC Prefixes per ASN: 29.07 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: 3.2 Max AfriNIC Region AS path length visible: 6 Number of AfriNIC region 32-bit ASNs visible in the Routing Table: 20 Number of AfriNIC addresses announced to Internet: 2595328 Equivalent to 0 /8s, 39 /16s and 154 /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 606 2153 464 SINET-AS Research Organization of Informa 7497 454 180 23 CSTNET-AS-AP Computer Network Information 1237 199 72 154 KREONET-AS-KR KISTI, KR 4538 184 4192 72 ERX-CERNET-BKB China Education and Resear 58647 182 18 2 KAGAWAU-AS Kagawa University, JP 7575 165 281 112 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 61 1466 35 ERX-TANET-ASN1 Taiwan Academic Network TA Complete listing at https://bgp.nsrc.org/REN/CENIC/data-ASnet-APNIC ARIN Region per AS prefix count summary --------------------------------------- ASN No of nets /20 equiv MaxAgg Description 8075 953 16037 779 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft C 376 197 162 151 RISQ-AS - Reseau dInformations Scientifiq 5786 197 16 1 UPRENET - University of Puerto Rico, PR 668 185 595 158 DNIC-AS-00668 - United States Department 2920 173 34 7 LACOE - Los Angeles County Office of Educ 2152 146 491 96 CENIC-2152 - CENIC, US 270 142 517 94 AS270 - National Aeronautics and Space Ad 18558 140 18 4 NETBLK-RCOEK - Riverside County Office of 81 115 455 35 NCREN - MCNC, US 21976 92 34 16 NJEDGE-NET - NJEDge.Net, Inc., US Complete listing at https://bgp.nsrc.org/REN/CENIC/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 100 1759 85 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/CENIC/data-ASnet-RIPE LACNIC Region per AS prefix count summary ----------------------------------------- ASN No of nets /20 equiv MaxAgg Description 1916 204 161 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 66 8 1 UNIVERSIDADE FEDERAL DE VICOSA, BR 2715 57 84 39 Fundacao Carlos Chagas Filho de Amparo a 19611 53 17 2 Associacao Antonio Vieira - Unisinos, BR 61468 52 3 21 CEDIA, EC 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/CENIC/data-ASnet-LACNIC AfriNIC Region per AS prefix count summary ------------------------------------------ ASN No of nets /20 equiv MaxAgg Description 36914 558 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 37501 11 49 6 UOFS, ZA 327700 11 16 1 MoRENet, MZ 37182 10 8 1 TERNET, TZ 37654 9 1 5 RwEdNet-AS, RW Complete listing at https://bgp.nsrc.org/REN/CENIC/data-ASnet-AFRINIC Global Per AS prefix count summary ---------------------------------- ASN No of nets /20 equiv MaxAgg Description 8075 953 16037 779 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft C 2907 606 2153 464 SINET-AS Research Organization of Informa 36914 558 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 786 209 1731 188 JANET Jisc Services Limited, GB 1916 204 161 40 Rede Nacional de Ensino e Pesquisa, BR 1237 199 72 154 KREONET-AS-KR KISTI, KR 376 197 162 151 RISQ-AS - Reseau dInformations Scientifiq Complete listing at https://bgp.nsrc.org/REN/CENIC/data-ASnet Global Per AS Maximum Aggregation summary ----------------------------------------- ASN No of nets Net Savings Description 36914 558 555 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 58647 182 180 KAGAWAU-AS Kagawa University, JP 2920 173 166 LACOE - Los Angeles County Office of Education, 1916 204 164 Rede Nacional de Ensino e Pesquisa, BR 2907 606 142 SINET-AS Research Organization of Information a 18558 140 136 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/CENIC/data-CIDRnet List of Unregistered Origin ASNs (Global) ----------------------------------------- Bad AS Designation Net Originated Transit AS Transit AS Name 65208 PRIVATE 63.225.1.0/24 11570 AS11570 - Eastern New M 26971 UNALLOCATED 129.111.0.0/16 276 OTS-AS-276 - University 64011 UNALLOCATED 130.215.0.0/16 10326 WPI - Worcester Polytec 65208 PRIVATE 206.206.156.0/22 11570 AS11570 - Eastern New M 65208 PRIVATE 216.161.32.0/23 11570 AS11570 - Eastern New M 401367 UNALLOCATED 216.186.25.0/24 10430 WA-K20 - Washington Sta Complete listing at https://bgp.nsrc.org/REN/CENIC/data-badAS Advertised Unallocated Addresses -------------------------------- Unassigned Network ASN Information AS Name 164.160.192.0/21 Origin: 37661 NRaE1-AS, NG 164.160.192.0/21 Transit: 37288 WACREN, SN 202.14.117.0/24 Origin: 17827 STOU-AS-TH Sukhothai Thammathirat Open U 202.14.117.0/24 Transit: 4621 UNINET-AS-AP UNINET-, TH 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/CENIC/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 /9:1 /10:3 /11:7 /12:25 /13:31 /14:61 /15:152 /16:2182 /17:448 /18:476 /19:613 /20:845 /21:903 /22:1461 /23:1599 /24:11252 /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 534 558 KENET-AS, KE 8075 196 953 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US 8895 100 103 ISU Internet Services Unit ISU, SA 31638 48 48 ASN-LEPIDA, IT 37215 38 44 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/CENIC/data-sXXas-nos Number of /24s announced per /8 block (Global) ---------------------------------------------- 1:2 2:1 4:2 5:20 6:5 8:13 12:2 13:33 14:96 20:21 23:12 24:2 31:4 35:10 37:28 38:12 40:2 41:235 42:17 44:6 45:41 46:5 47:1 49:13 50:7 52:5 58:14 59:20 60:6 61:3 62:14 63:34 64:56 65:6 66:75 67:47 68:17 69:31 70:4 72:6 74:61 76:36 77:4 78:3 79:6 80:8 81:28 82:3 83:7 84:5 85:26 86:4 87:1 89:18 91:44 92:3 93:14 94:9 95:2 96:5 97:2 98:5 101:5 102:8 103:373 104:82 108:11 109:10 111:8 113:6 114:24 115:1 116:9 117:6 118:33 119:24 121:17 122:8 123:8 124:42 125:4 128:61 129:48 130:104 131:74 132:64 133:157 134:122 135:6 136:200 137:68 138:18 139:5 140:35 141:7 142:39 143:29 144:14 145:13 146:138 147:72 148:235 149:11 150:42 151:21 152:129 153:17 154:39 155:99 156:124 157:29 158:31 159:116 160:36 161:49 162:33 163:80 164:17 165:61 166:3 167:39 168:81 169:7 170:33 171:1 172:1 173:7 175:15 176:1 177:6 178:4 179:12 180:16 181:1 182:11 184:6 185:78 186:4 187:8 188:25 190:17 191:13 192:1583 193:310 194:118 195:100 196:149 197:345 198:498 199:321 200:293 201:7 202:604 203:458 204:401 205:132 206:214 207:218 208:59 209:106 210:231 211:15 212:144 213:9 214:8 216:106 217:25 218:21 219:7 220:16 222:4 223:17 End of report