January 2026 - NANOG - lists.nanog.org

Seeking Microsoft AS8075 contact
by John Stitt 05 Jan '26

05 Jan '26

Could someone from Microsoft AS8075 reach out to us off list? We've been having a number of customers complaining because their Xbox is saying it "Can't get a Teredo IP address". Seems to be related to the DNS response the client gets, as we've been able to work around the issue by trying different DNS providers. One of our network admins has been battling this while I've been out on vacation the past two weeks. Some of the customers are able to replicate the issue when using their cell provider, so it's not limited to just our network having this issue. We have some packet captures we can share, and an employee who is able to replicate the issue at their house for further testing. Attempting to contact Microsoft via other routes hasn't gotten him anywhere. Thanks, John Stitt HES energynet

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Important Network and Datacenter Papers Everyone Should Read
by Ryan Hamel 03 Jan '26

03 Jan '26

Hey y'all, A collaborative Google Doc was started by Daniel Goulding on "Important Network and Datacenter Papers Everyone Should Read" (https://docs.google.com/document/d/1twMAtoCTx_6AcuD2aocrokLLuCQZMI9Fv9kFJ6Y…) If you have any suggestions, please add them as comments to the document. You can also share them here, and also provide feedback. I have also mentioned this in the Discord (https://discord.nanog.org) for any real-time discussions. Kind regards, Ryan Hamel

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Weekly Global IPv4 Routing Table Report
by Routing Table Analysis Role Account 02 Jan '26

02 Jan '26

This is an automated weekly mailing describing the state of the Global IPv4 Routing Table as seen from APNIC's router in Japan. The posting is sent to APOPS, NANOG, AfNOG, SANOG, PacNOG, SAFNOG UKNOF, TZNOG, MENOG, BJNOG, SDNOG, CMNOG, LACNOG and the RIPE Routing WG. Daily listings are sent to bgp-stats(a)lists.apnic.net. For historical data, please see https://thyme.apnic.net. If you have any comments please contact Philip Smith <pfsinoz(a)gmail.com>. IPv4 Routing Table Report 04:00 +10GMT Sat 03 Jan, 2026 IPv4 BGP Table (Global) as seen at Japan. Report Website: https://thyme.apnic.net Detailed Analysis: https://thyme.apnic.net/current/ Analysis Summary ---------------- BGP routing table entries examined: 1025059 Prefixes after maximum aggregation (per Origin AS): 394695 Deaggregation factor: 2.60 Unique aggregates announced (without unneeded subnets): 506094 Number of IPv4 prefixes with a valid ROA: 604856 Number of IPv4 prefixes with an invalid ROA: 1542 Number of IPv4 prefixes with no ROA: 418661 Total ASes present in the Internet Routing Table: 77699 Prefixes per ASN: 13.19 Origin-only ASes present in the Internet Routing Table: 66776 Origin ASes announcing only one prefix: 27122 Transit ASes present in the Internet Routing Table: 10923 Transit-only ASes present in the Internet Routing Table: 548 Average AS path length visible in the Internet Routing Table: 4.7 Max AS path length visible: 69 Max AS path prepend of ASN (269326) 61 Prefixes from unregistered ASNs in the Routing Table: 958 Number of instances of unregistered ASNs: 996 Number of 32-bit ASNs allocated by the RIRs: 48311 Number of 32-bit ASNs visible in the Routing Table: 39551 Prefixes from 32-bit ASNs in the Routing Table: 219847 Number of bogon 32-bit ASNs visible in the Routing Table: 109 Special use prefixes present in the Routing Table: 1 Prefixes being announced from unallocated address space: 600 Number of addresses announced to Internet: 3105877632 Equivalent to 185 /8s, 31 /16s and 238 /24s Percentage of available address space announced: 83.9 Percentage of allocated address space announced: 83.9 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: 335192 APNIC Region Analysis Summary ----------------------------- Prefixes being announced by APNIC Region ASes: 278371 Total APNIC prefixes after maximum aggregation: 81521 APNIC Deaggregation factor: 3.41 Prefixes being announced from the APNIC address blocks: 264996 Unique aggregates announced from the APNIC address blocks: 106445 APNIC Region origin ASes present in the Internet Routing Table: 14973 APNIC Prefixes per ASN: 17.70 APNIC Region origin ASes announcing only one prefix: 4560 APNIC Region transit ASes present in the Internet Routing Table: 1976 Average APNIC Region AS path length visible: 4.7 Max APNIC Region AS path length visible: 34 Number of APNIC region 32-bit ASNs visible in the Routing Table: 10529 Number of APNIC addresses announced to Internet: 754145792 Equivalent to 44 /8s, 243 /16s and 90 /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: 300437 Total ARIN prefixes after maximum aggregation: 134975 ARIN Deaggregation factor: 2.23 Prefixes being announced from the ARIN address blocks: 300635 Unique aggregates announced from the ARIN address blocks: 145718 ARIN Region origin ASes present in the Internet Routing Table: 19383 ARIN Prefixes per ASN: 15.51 ARIN Region origin ASes announcing only one prefix: 7058 ARIN Region transit ASes present in the Internet Routing Table: 1933 Average ARIN Region AS path length visible: 4.3 Max ARIN Region AS path length visible: 28 Number of ARIN region 32-bit ASNs visible in the Routing Table: 5423 Number of ARIN addresses announced to Internet: 1342584064 Equivalent to 80 /8s, 6 /16s and 53 /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: 282998 Total RIPE prefixes after maximum aggregation: 139948 RIPE Deaggregation factor: 2.02 Prefixes being announced from the RIPE address blocks: 284047 Unique aggregates announced from the RIPE address blocks: 184144 RIPE Region origin ASes present in the Internet Routing Table: 29125 RIPE Prefixes per ASN: 9.75 RIPE Region origin ASes announcing only one prefix: 12079 RIPE Region transit ASes present in the Internet Routing Table: 3945 Average RIPE Region AS path length visible: 4.8 Max RIPE Region AS path length visible: 31 Number of RIPE region 32-bit ASNs visible in the Routing Table: 12896 Number of RIPE addresses announced to Internet: 735129984 Equivalent to 43 /8s, 209 /16s and 49 /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: 126129 Total LACNIC prefixes after maximum aggregation: 30662 LACNIC Deaggregation factor: 4.11 Prefixes being announced from the LACNIC address blocks: 121935 Unique aggregates announced from the LACNIC address blocks: 49792 LACNIC Region origin ASes present in the Internet Routing Table: 11342 LACNIC Prefixes per ASN: 10.75 LACNIC Region origin ASes announcing only one prefix: 2691 LACNIC Region transit ASes present in the Internet Routing Table: 2529 Average LACNIC Region AS path length visible: 5.4 Max LACNIC Region AS path length visible: 69 Number of LACNIC region 32-bit ASNs visible in the Routing Table: 9337 Number of LACNIC addresses announced to Internet: 170540800 Equivalent to 10 /8s, 42 /16s and 63 /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: 36166 Total AfriNIC prefixes after maximum aggregation: 6939 AfriNIC Deaggregation factor: 5.21 Prefixes being announced from the AfriNIC address blocks: 52846 Unique aggregates announced from the AfriNIC address blocks: 19531 AfriNIC Region origin ASes present in the Internet Routing Table: 2003 AfriNIC Prefixes per ASN: 26.38 AfriNIC Region origin ASes announcing only one prefix: 734 AfriNIC Region transit ASes present in the Internet Routing Table: 384 Average AfriNIC Region AS path length visible: 5.3 Max AfriNIC Region AS path length visible: 44 Number of AfriNIC region 32-bit ASNs visible in the Routing Table: 1366 Number of AfriNIC addresses announced to Internet: 103171072 Equivalent to 6 /8s, 38 /16s and 68 /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 9808 13471 8945 105 CHINAMOBILE-CN China Mobile Communication 7545 6037 834 581 TPG-INTERNET-AP TPG Telecom Limited, AU 4538 5023 4193 77 ERX-CERNET-BKB China Education and Resear 9498 4669 542 335 BBIL-AP BHARTI Airtel Ltd., IN 7552 4056 1332 29 VIETEL-AS-AP Viettel Group, VN 7713 3732 1044 65 TELKOMNET-AS-AP PT Telekomunikasi Indones 56046 3398 831 184 CMNET-JIANGSU-AP China Mobile communicati 45899 3332 1868 98 VNPT-AS-VN VNPT Corp, VN 17561 3120 196 617 LCS-AS-AP LARUS Limited, HK 24560 2962 865 500 AIRTELBROADBAND-AS-AP Bharti Airtel Ltd., Complete listing at https://thyme.apnic.net/current/data-ASnet-APNIC ARIN Region per AS prefix count summary --------------------------------------- ASN No of nets /20 equiv MaxAgg Description 16509 14035 38462 5430 AMAZON-02, US 22773 4750 3116 377 ASN-CXA-ALL-CCI-22773-RDC, US 11492 4691 311 946 CABLEONE, US 7155 3861 286 85 VIASAT-SP-BACKBONE, US 6327 3690 1320 82 SHAW, CA 396982 3318 4867 492 GOOGLE-CLOUD-PLATFORM, US 749 3143 54729 2394 DNIC-AS-00749, US 174 3065 8770 862 COGENT-174, US 16625 2855 1221 2136 AKAMAI-AS, US 36352 2705 222 888 AS-COLOCROSSING, US Complete listing at https://thyme.apnic.net/current/data-ASnet-ARIN RIPE Region per AS prefix count summary --------------------------------------- ASN No of nets /20 equiv MaxAgg Description 12479 7278 1711 149 UNI2-AS, ES 39891 4969 306 72 ALJAWWALSTC-AS, SA 9009 3947 368 2270 M247, RO 20940 3830 3393 111 AKAMAI-ASN1, NL 12389 3175 2317 871 ROSTELECOM-AS PJSC Rostelecom. Technical 212238 2561 182 1860 CDNEXT, GB 34984 2421 371 574 TELLCOM-AS, TR 8452 1702 1852 14 TE-AS TE-AS, EG 203020 1615 242 783 HOSTROYALE, IN 13188 1607 100 27 TRIOLAN, UA Complete listing at https://thyme.apnic.net/current/data-ASnet-RIPE LACNIC Region per AS prefix count summary ----------------------------------------- ASN No of nets /20 equiv MaxAgg Description 8151 12648 3293 592 UNINET, MX 10620 3434 457 1108 Telmex Colombia S.A., CO 13999 2480 506 350 Mega Cable, S.A. de C.V., MX 11830 1992 369 65 Instituto Costarricense de Electricidad y 11664 1372 278 33 Techtel LMDS Comunicaciones Interactivas 28573 1370 2430 270 Claro NXT Telecomunicacoes Ltda, BR 3816 1339 770 213 COLOMBIA TELECOMUNICACIONES S.A. ESP BIC, 6147 1260 371 22 Telefonica del Peru S.A.A., PE 22884 1057 67 359 TOTAL PLAY TELECOMUNICACIONES SA DE CV, M 26615 1013 2486 56 TIM SA, BR Complete listing at https://thyme.apnic.net/current/data-ASnet-LACNIC AfriNIC Region per AS prefix count summary ------------------------------------------ ASN No of nets /20 equiv MaxAgg Description 24835 1982 638 33 RAYA-AS, EG 36992 1847 1534 341 ETISALAT-MISR, EG 24863 1267 389 16 LINKdotNET-AS, EG 36903 1232 555 98 MT-MPLS, MA 36935 1109 523 46 Vodafone-, EG 37069 1100 1096 13 MOBINIL, EG 29571 1072 94 22 ORANGE-COTE-IVOIRE, CI 20011 580 154 212 NTT-DATA-Inc, ZA 36914 556 82 3 KENET-AS, KE 328608 554 48 161 Africa-on-Cloud-AS, ZA Complete listing at https://thyme.apnic.net/current/data-ASnet-AFRINIC Global Per AS prefix count summary ---------------------------------- ASN No of nets /20 equiv MaxAgg Description 16509 14035 38462 5430 AMAZON-02, US 9808 13471 8945 105 CHINAMOBILE-CN China Mobile Communication 8151 12648 3293 592 UNINET, MX 12479 7278 1711 149 UNI2-AS, ES 7545 6037 834 581 TPG-INTERNET-AP TPG Telecom Limited, AU 4538 5023 4193 77 ERX-CERNET-BKB China Education and Resear 39891 4969 306 72 ALJAWWALSTC-AS, SA 22773 4750 3116 377 ASN-CXA-ALL-CCI-22773-RDC, US 11492 4691 311 946 CABLEONE, US 9498 4669 542 335 BBIL-AP BHARTI Airtel Ltd., IN Complete listing at https://thyme.apnic.net/current/data-ASnet Global Per AS Maximum Aggregation summary ----------------------------------------- ASN No of nets Net Savings Description 9808 13471 13366 CHINAMOBILE-CN China Mobile Communications Grou 8151 12648 12056 UNINET, MX 12479 7278 7129 UNI2-AS, ES 7545 6037 5456 TPG-INTERNET-AP TPG Telecom Limited, AU 4538 5023 4946 ERX-CERNET-BKB China Education and Research Net 39891 4969 4897 ALJAWWALSTC-AS, SA 22773 4750 4373 ASN-CXA-ALL-CCI-22773-RDC, US 9498 4669 4334 BBIL-AP BHARTI Airtel Ltd., IN 7552 4056 4027 VIETEL-AS-AP Viettel Group, VN 7155 3861 3776 VIASAT-SP-BACKBONE, US Complete listing at https://thyme.apnic.net/current/data-CIDRnet List of Unregistered Origin ASNs (Global) ----------------------------------------- Bad AS Designation Net Originated Transit AS Transit AS Name 393266 UNALLOCATED 8.23.52.0/24 46887 CROWNCASTLE-AS46887, US 396894 UNALLOCATED 8.28.201.0/24 3356 LEVEL3, US 394936 UNALLOCATED 8.33.224.0/24 22442 HOU-PHONOSCOPE, US 395195 UNALLOCATED 8.38.115.0/24 3356 LEVEL3, US 1782 UNALLOCATED 8.42.19.0/24 3356 LEVEL3, US 54739 UNALLOCATED 8.44.198.0/23 13335 CLOUDFLARENET, US 13342 UNALLOCATED 12.17.5.0/24 174 COGENT-174, US 26345 UNALLOCATED 12.21.93.0/24 40264 TWC-40264-WI-MN-UPPERMI 396831 UNALLOCATED 12.23.198.0/24 7018 ATT-INTERNET4, US 21861 UNALLOCATED 12.37.59.0/24 7018 ATT-INTERNET4, US Complete listing at https://thyme.apnic.net/current/data-badAS Prefixes from the Special Purpose Address Registry (Global) ----------------------------------------------------------- Prefix Origin AS Description 192.88.99.0/24 6939 HURRICANE, US Complete listing at https://thyme.apnic.net/current/data-spar Advertised Unallocated Addresses -------------------------------- Unassigned Network ASN Information AS Name 23.137.48.0/24 Origin: 16904 ARVIG-16904, US 23.137.48.0/24 Transit: 3257 GTT-BACKBONE GTT, US 23.137.200.0/24 Origin: 16276 OVH, FR 23.137.200.0/24 Transit: 2516 KDDI KDDI CORPORATION, JP 23.140.216.0/24 Origin: 27176 DATAWAGON, US 23.140.216.0/24 Transit: 20278 NEXEON, US 23.141.0.0/24 Origin: 395350 RESERVED, ZZ 23.141.0.0/24 Transit: 11426 TWC-11426-CAROLINAS, US 23.142.24.0/24 Origin: 62164 HEYMMAN-2, CA 23.142.24.0/24 Transit: 64236 UNREAL-SERVERS, US Complete listing at https://thyme.apnic.net/current/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 /8:16 /9:14 /10:41 /11:93 /12:299 /13:579 /14:1198 /15:2093 /16:13718 /17:8313 /18:13597 /19:25081 /20:45674 /21:52631 /22:113558 /23:106093 /24:641364 /25:697 /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 8151 6852 12648 UNINET, MX 12479 6209 7278 UNI2-AS, ES 39891 3655 4969 ALJAWWALSTC-AS, SA 11492 3536 4691 CABLEONE, US 6327 3478 3690 SHAW, CA 22773 3054 4750 ASN-CXA-ALL-CCI-22773-RDC, US 7155 2820 3861 VIASAT-SP-BACKBONE, US 16509 2466 14035 AMAZON-02, US 30036 2306 2649 MEDIACOM-ENTERPRISE-BUSINESS, US 10620 2214 3434 Telmex Colombia S.A., CO Complete listing at https://thyme.apnic.net/current/data-sXXas-nos Number of /24s announced per /8 block (Global) ---------------------------------------------- 1:1807 2:1526 3:980 4:10 5:4933 6:187 7:6 8:1528 9:14 11:172 12:1234 13:611 14:2666 15:418 16:275 17:383 18:914 20:591 21:4 22:188 23:8085 24:2562 25:2 27:2743 29:19 31:3390 32:32 33:1 34:81 35:290 36:4634 37:4526 38:9909 39:1225 40:434 41:4489 42:964 43:2885 44:411 45:19631 46:5050 47:398 49:2150 50:2051 51:599 52:1251 54:229 55:1127 56:11 57:310 58:2216 59:1421 60:1172 61:3063 62:3099 63:1770 64:6111 65:2130 66:6019 67:3261 68:1505 69:4221 70:1029 71:619 72:3085 74:2960 75:1518 76:603 77:2757 78:1926 79:1783 80:2316 81:2089 82:3938 83:1472 84:2032 85:3670 86:1101 87:2352 88:1362 89:4631 90:833 91:8432 92:2830 93:3014 94:4277 95:4562 96:1447 97:313 98:957 99:789 100:68 101:1263 102:4333 103:32298 104:5471 105:769 106:922 107:2815 108:1224 109:4257 110:2306 111:4066 112:2883 113:1692 114:2101 115:2241 116:2160 117:3248 118:2487 119:2101 120:2455 121:1568 122:2965 123:2292 124:1677 125:2972 126:125 128:1582 129:967 130:1556 131:2266 132:763 133:462 134:1630 135:539 136:1495 137:1278 138:2983 139:1595 140:1833 141:1562 142:2433 143:2133 144:1401 145:627 146:2195 147:2142 148:2778 149:2923 150:1318 151:2590 152:2262 153:844 154:9523 155:2305 156:4566 157:2238 158:1483 159:2734 160:3642 161:1994 162:4003 163:2328 164:1960 165:2641 166:1311 167:2198 168:3927 169:812 170:5466 171:1117 172:4519 173:3426 174:903 175:1344 176:3788 177:4779 178:4310 179:2297 180:2847 181:4358 182:3868 183:2470 184:2052 185:21707 186:5504 187:4781 188:4604 189:4480 190:9672 191:1580 192:11449 193:9519 194:7872 195:5657 196:3266 197:3194 198:6241 199:6115 200:8186 201:6387 202:10769 203:10523 204:4700 205:3768 206:4423 207:3987 208:4364 209:5506 210:4980 211:2774 212:4950 213:4039 214:1062 215:54 216:7125 217:3460 218:1670 219:581 220:2190 221:1299 222:917 223:3263 End of report

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