51.138.12.91 - Ajax Whois

No reverse DNS
Not on blocklists

Network

cloud

Held by

MICROSOFT-MAINT

Range

51.138.0.0 - 51.138.255.255

CIDR

51.138.0.0/16

Type

LEGACY

Country

Registered on

2025-09-05

Last updated

2025-09-05

Status

active

Report abuse to

abuse@microsoft.com

Contacts

Administrative
Divya Quamara DH5439-RIPE
One Microsoft Way
Redmond, WA 98052
+1-425-882-8080
Holder
MICROSOFT-MAINT
Technical
Microsoft Routing, Peering, and DNS MRPA3-RIPE
One Microsoft Way
Redmond, WA 98052
Abuse
Microsoft Abuse Contact MAC274-RIPE
One Microsoft Way
Redmond, WA 98052
abuse@microsoft.com

Reverse DNS

Names: None

Network

Announced by: AS8075 Microsoft Corporation
Route: 51.138.0.0/16, carried by 3,294 of bgp.tools' BGP feeds
Kind: Content
Country: US
Tagged: Tor services, Server Hosting, Anycast, Internet Critical Infra, Tranco 10k Host, Validating RPKI ROV

Upstreams and peers

AS1299 Arelion (fka. Telia Carrier)331 paths
AS4755 TATA Communications (formerly VSNL)256 paths
AS6939 Hurricane Electric LLC241 paths
AS6762 Telecom Italia Sparkle (Seabone)206 paths
AS3356 Lumen (Level 3)192 paths
AS12956 Telxius (Telefonica Global)155 paths
AS174 Cogent Communications, LLC138 paths
AS6453 TATA Communications (America) Inc56 paths
AS9002 RETN Limited49 paths
AS34549 meerfarbig GmbH & Co. KG39 paths
AS3491 PCCW Global (HK) Ltd.31 paths
AS2914 NTT America, Inc.30 paths

And 107 more

Downstreams

AS8069 Microsoft Corporation898 paths
AS8068 Microsoft Corporation676 paths
AS8070 Microsoft Corporation312 paths
AS3598 Microsoft Corporation311 paths
AS5761 Microsoft Corporation305 paths
AS58593 Microsoft Azure China (Shanghai Blue Cloud)299 paths
AS62540 Drake Holdings LLC268 paths

From RIPEstat

Routes AS8075 announces

1,235 IPv4 prefixes covering 81,118,720 addresses, and 123 IPv6 prefixes

IPv4

And 1,185 more

IPv6

And 73 more

From bgp.tools

Peering

Name: Microsoft
Type: Content
Peering policy: Selective
Traffic ratio: Mostly Outbound
Scope: Global
AS-SET: AS-MICROSOFT
Website: http://www.microsoft.com

Internet exchanges

Exchange	Speed	Route servers
1-IX EU	200 Gbit/s over 2 ports	No
AKL-IX (Auckland NZ): AKL-IX	200 Gbit/s over 2 ports	No
AMS-IX	800 Gbit/s over 2 ports	No
AMS-IX Hyderabad	200 Gbit/s over 2 ports	No
AMS-IX Lagos: Main	40 Gbit/s over 2 ports	No
AMS-IX Mumbai	40 Gbit/s over 2 ports	No
Any2Chicago	200 Gbit/s over 2 ports	No
Any2Denver	200 Gbit/s over 2 ports	No
Any2East	200 Gbit/s over 2 ports	No
Any2West	200 Gbit/s over 2 ports	No
AR-IX Cabase - Argentina	200 Gbit/s over 2 ports	No
Asteroid Amsterdam: Asteroid Amsterdam Peering LAN	10 Gbit/s	No
Balcan-IX	200 Gbit/s over 2 ports	No
BBIX Hong Kong	200 Gbit/s over 2 ports	No
BBIX Manila	200 Gbit/s over 2 ports	No
BBIX Osaka	200 Gbit/s over 2 ports	No
BBIX Singapore	200 Gbit/s over 2 ports	No
BBIX Tokyo	400 Gbit/s over 2 ports	No
BCIX: BCIX Peering LAN	200 Gbit/s over 2 ports	No
BIX	200 Gbit/s over 2 ports	No
BIX.BG: Main	200 Gbit/s over 2 ports	No
BNIX	400 Gbit/s over 2 ports	No
Boston Internet Exchange	200 Gbit/s over 2 ports	No
CANIX Montreal	200 Gbit/s over 2 ports	No
CANIX Quebec City	200 Gbit/s over 2 ports	No
CATNIX	200 Gbit/s over 2 ports	No
center3 IX Jeddah: Main	20 Gbit/s over 2 ports	No
ChIX	200 Gbit/s over 2 ports	No
CINX: CINX Peering	200 Gbit/s over 2 ports	No
CitraIX Yogyakarta	100 Gbit/s	No
CIX	40 Gbit/s over 2 ports	No
CIX-ATL	200 Gbit/s over 2 ports	No
CIXP	10 Gbit/s	No
DE-CIX Athens	20 Gbit/s over 2 ports	No
DE-CIX Barcelona	20 Gbit/s over 2 ports	No
DE-CIX Chennai: DE-CIX Chennai Peering LAN	20 Gbit/s over 2 ports	No
DE-CIX Chicago	200 Gbit/s over 2 ports	No
DE-CIX Dallas: DE-CIX Dallas Peering LAN	100 Gbit/s	No
DE-CIX Delhi: DE-CIX Delhi Peering LAN	40 Gbit/s over 2 ports	No
DE-CIX Dusseldorf: DE-CIX Dusseldorf Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX Frankfurt: DE-CIX Frankfurt Peering LAN	1.2 Tbit/s over 2 ports	No
DE-CIX Hamburg: DE-CIX Hamburg Peering LAN	20 Gbit/s over 2 ports	No
DE-CIX Istanbul: DE-CIX Istanbul Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX Kuala Lumpur	10 Gbit/s	No
DE-CIX Lisbon: DE-CIX Lisbon Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX Mexico	200 Gbit/s over 2 ports	No
DE-CIX Mumbai: DE-CIX Mumbai Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX Munich: DE-CIX Munich Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX New York: DE-CIX New York Peering LAN	200 Gbit/s over 2 ports	No
DE-CIX Phoenix	200 Gbit/s over 2 ports	No

And 157 more

Facilities

Equinix DX1 - Dubai, Dubai, AE
Pacheco Datacenter EZE1 Argentina Buenos Aires, Buenos Aires, AR
Digital Realty VIE1/2 - Vienna, Vienna, AT
NTT Vienna1 Data Center (VIE1), Vienna, AT
NEXTDC B2, Fortitude Valley, AU
CDC Canberra FY1, Fyshwick, AU
CDC Canberra HU1, Hume, AU
Equinix ME1/ME2 - Melbourne, Melbourne, AU
NEXTDC M1, Melbourne, AU
NEXTDC P1, Málaga, AU
NEXTDC P2, Perth, AU
Equinix SY1/SY2 - Sydney, Sydney, AU
NEXTDC S1, Sydney, AU
Digital Realty BRU1 - Brussels, Brussels, BE
LCL Brussels (Diegem), Brussels, BE
Digital Realty BRU4 - Brussels, Zaventem, BE
TELEPOINT Sofia Centre, Sofia, BG
Equinix SP2 - São Paulo, Barueri, BR
Equinix SP4 - São Paulo, Barueri, BR
Ascenty CPS01 - Campinas, Campinas, BR
Tecto TFOR1/2 (ex Globenet CLS & Big Lobster), Fortaleza, BR
Cirion Rio de Janeiro - RIO1, Rio de Janeiro, BR
Equinix RJ2 - Rio de Janeiro, Rio de Janeiro, BR
TIVIT Sao Paulo, São Paulo, BR
Cologix MTL3, Montreal, CA
Cologix MTL7, Montreal, CA
Vantage Data Centers (QC2), Quebec, CA
Cologix TOR1, Toronto, CA
Telehouse Toronto (905 King Street West), Toronto, CA
Cologix VAN1, Vancouver, CA
Equinix GV2 - Geneva, West, Geneva, CH
Digital Realty Zurich ZUR1, Glattbrugg, CH
Equinix ZH5 - Zurich, South, Zurich, CH
Cirion Santiago de Chile - SAN1, Santiago, CL
EdgeConneX Santiago (EDCSCL01), Santiago, CL
Equinix BG1 - Bogota, Bogota, CO
CE Colo Prague, Prague, CZ
NTT Berlin 1 Data Center (BER1), Berlin, DE
Digital Realty Dusseldorf DUS1-3, Düsseldorf, DE
Digital Realty Frankfurt FRA1-27, Frankfurt, DE
Equinix FR7 - Frankfurt, Gutleutstrasse, Frankfurt, DE
EdgeConneX Munich (EDCMUC01), Munich, DE
Digital Realty Copenhagen CPH1-3, Copenhagen, DK
GlobalConnect Taastrup 1 (CPH1), Taastrup, DK
Regional Data Hub (RDH), Giza, EG
Equinix MD2 - Madrid, Alcobendas, ES
Equinix BA1 - Barcelona, Barcelona, ES
Digital Realty Madrid MAD1-2, Madrid, ES
Digital Realty Madrid MAD3, Madrid, ES
Equinix HE3 - Helsinki, Suvilahti, Helsinki, FI

And 117 more

From PeeringDB

Location

Location: Amsterdam, North Holland, The Netherlands
Accuracy: Within 20 km

Location from GeoLite2 data created by MaxMind

Blocklists

Spamhaus ZEN Not listed
SpamCop Not listed
Mailspike Not listed
PSBL Not listed