ASN AS45139 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS45139?

AS45139 is listed under Microsoft Singapore Pte. Ltd..

What do peers, upstreams, and downstreams mean in ASN data?

Peers are lateral network interconnections, upstreams are transit providers, and downstreams are customer networks receiving connectivity.

What are routes and IP ranges for an ASN?

Routes and IP ranges are the network prefixes announced by the ASN on the internet and show the address space it originates.

Why is WHOIS data shown for an ASN?

WHOIS data provides registration and contact context for ASN ownership, administration, and operational reference.

How can I access the full ASN tables?

The page shows a preview of large ASN datasets. Use the page controls to load more rows, and upgrade to a paid plan for complete access.

AS45139 Microsoft Singapore Pte. Ltd.

ASN Lookup Tool

Microsoft Singapore Pte. Ltd.

US 4 Routes

AS Data

AS45139

AS45139 – Microsoft Singapore Pte. Ltd.

AS Number	45139
AS Name	Microsoft Corp
Organization	Microsoft Singapore Pte. Ltd. (org-mspl4-ap)
Country	US
Number of IPv4 Routes	2
Number of IPv6 Routes	2
ASN type	BUSINESS
Registry	APNIC
Date Allocated	2008-03-07

ASN Intelligence API for production workflows

Use ASN data for AS45139 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
2404:f801:8020::/48	AS45139	Microsoft Singapore Pte. Ltd.	Microsoft Singapore Pte. Ltd.	~1×10²⁴
2404:f801:802c::/48	AS45139	Microsoft Singapore Pte. Ltd.	Microsoft Singapore Pte. Ltd.	~1×10²⁴
167.220.226.0/23	AS45139	Microsoft Singapore Pte. Ltd.	Microsoft Singapore Pte. Ltd.	512
167.220.227.0/24	AS45139	Microsoft Singapore Pte. Ltd.	Microsoft Singapore Pte. Ltd.	256

Raw Whois Response

[ JPNIC database provides information regarding IP address and ASN. Its use   ]
[ is restricted to network administration purposes. For further information,  ]
[ use 'whois -h whois.nic.ad.jp help'. To only display English output,        ]
[ add '/e' at the end of command, e.g. 'whois -h whois.nic.ad.jp xxx/e'.      ]

No match!!

Reference: WHOIS servers of RIRs
  APNIC WHOIS(whois.apnic.net)
  ARIN WHOIS(whois.arin.net)
  RIPE WHOIS(apps.db.ripe.net)
  LACNIC WHOIS(whois.lacnic.net)
  AfriNIC WHOIS(whois.afrinic.net)

% [whois.apnic.net]
% Whois data copyright terms    http://www.apnic.net/db/dbcopyright.html

% Information related to 'AS45056 - AS46079'

as-block:       AS45056 - AS46079
descr:          APNIC ASN block
remarks:        These AS numbers are further assigned by APNIC
remarks:        to APNIC members and end-users in the APNIC region
admin-c:        HM20-AP
tech-c:         HM20-AP
mnt-by:         APNIC-HM
mnt-lower:      APNIC-HM
last-modified:  2009-09-29T05:48:11Z
source:         APNIC

role:           APNIC Hostmaster
address:        PO Box 3646
address:        South Brisbane
address:        QLD 4101
country:        AU
phone:          +61 7 3858 3100
fax-no:         +61 7 3858 3199
e-mail:         helpdesk@apnic.net
admin-c:        AMS11-AP
tech-c:         AH256-AP
nic-hdl:        HM20-AP
remarks:        Administrator for APNIC
notify:         hostmaster@apnic.net
mnt-by:         MAINT-APNIC-AP
last-modified:  2026-08-26T00:40:00Z
source:         APNIC

% Information related to 'AS45139'

% Abuse contact for 'AS45139' is 'abuse@microsoft.com'

aut-num:        AS45139
as-name:        MICROSOFT-AS-AP
descr:          Microsoft Corp
country:        JP
import:         from AS6175 action pref=100; accept ANY
import:         from AS18084 action pref=100; accept ANY
export:         to AS6175 announce AS45139
export:         to AS18084 announce AS45139
default:        to AS18084 action pref=1; networks ANY
default:        to AS6175 action pref=2; networks ANY
remarks:        For routing problems with this ASN contact the admin-c
org:            ORG-MSPL4-AP
admin-c:        NK160-AP
tech-c:         NK160-AP
abuse-c:        AM2589-AP
notify:         naokikit@microsoft.com
mnt-lower:      MAINT-AP-MSFT
mnt-routes:     MAINT-AP-MSFT
mnt-by:         APNIC-HM
mnt-irt:        IRT-MICROSOFT-APNIC-SG
last-modified:  2020-07-07T05:09:05Z
source:         APNIC

irt:            IRT-MICROSOFT-APNIC-SG
address:        One Microsft Way
address:        Redmond, WA 98052
address:        US
e-mail:         abuse@microsoft.com
abuse-mailbox:  abuse@microsoft.com
admin-c:        MP234-AP
tech-c:         MP234-AP
auth:           # Filtered
remarks:        abuse@microsoft.com is invalid
mnt-by:         MAINT-AP-MICROSOFT
last-modified:  2025-11-18T00:26:27Z
source:         APNIC

organisation:   ORG-MSPL4-AP
org-name:       Microsoft Singapore Pte. Ltd.
country:        US
address:        One Microsoft Way
phone:          +011-425-706-8080
fax-no:         +011-425-936-7329
e-mail:         dawn.bedard@microsoft.com
mnt-ref:        APNIC-HM
mnt-by:         APNIC-HM
last-modified:  2020-05-27T12:56:32Z
source:         APNIC

role:           ABUSE MICROSOFTAPNICSG
country:        ZZ
address:        One Microsft Way
address:        Redmond, WA 98052
address:        US
phone:          +000000000
e-mail:         abuse@microsoft.com
admin-c:        MP234-AP
tech-c:         MP234-AP
nic-hdl:        AM2589-AP
remarks:        Generated from irt object IRT-MICROSOFT-APNIC-SG
remarks:        abuse@microsoft.com is invalid
abuse-mailbox:  abuse@microsoft.com
mnt-by:         APNIC-ABUSE
last-modified:  2025-09-04T18:10:10Z
source:         APNIC

person:         Naoki Kitajima
nic-hdl:        NK160-AP
e-mail:         naokikit@microsoft.com
address:        Akasaka Garden City 4-15-1 Akasaka, Minato-ku, Tokyo 107-0052
phone:          +81-3-4512-3346
fax-no:         +81-3-4512-3416
country:        JP
mnt-by:         MAINT-AP-MSFT
last-modified:  2008-09-04T07:50:54Z
source:         APNIC

% This query was served by the APNIC Whois Service version 1.88.48 (WHOIS-US2)

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.apnic.net",
  "as_blocks" : [ {
    "as_block" : "AS45056 - AS46079",
    "description" : [ "APNIC ASN block" ],
    "admin_contacts" : [ "HM20-AP" ],
    "tech_contacts" : [ "HM20-AP" ],
    "remarks" : [ "These AS numbers are further assigned by APNIC", "to APNIC members and end-users in the APNIC region" ],
    "mnt_by" : [ "APNIC-HM" ],
    "mnt_lower" : [ "APNIC-HM" ],
    "date_updated" : "2009-09-29",
    "source" : "APNIC"
  } ],
  "aut_nums" : [ {
    "aut_num" : "AS45139",
    "as_name" : "MICROSOFT-AS-AP",
    "description" : [ "Microsoft Corp" ],
    "country" : "JP",
    "import" : [ "from AS6175 action pref=100; accept ANY", "from AS18084 action pref=100; accept ANY" ],
    "export" : [ "to AS6175 announce AS45139", "to AS18084 announce AS45139" ],
    "default" : [ "to AS18084 action pref=1; networks ANY", "to AS6175 action pref=2; networks ANY" ],
    "organization" : "ORG-MSPL4-AP",
    "admin_contacts" : [ "NK160-AP" ],
    "tech_contacts" : [ "NK160-AP" ],
    "abuse_contacts" : [ "AM2589-AP" ],
    "remarks" : [ "For routing problems with this ASN contact the admin-c" ],
    "notify" : [ "naokikit@microsoft.com" ],
    "mnt_irt" : [ "IRT-MICROSOFT-APNIC-SG" ],
    "mnt_lower" : [ "MAINT-AP-MSFT" ],
    "mnt_routes" : [ "MAINT-AP-MSFT" ],
    "mnt_by" : [ "APNIC-HM" ],
    "date_updated" : "2020-07-07",
    "source" : "APNIC"
  } ],
  "irt" : {
    "handle" : "IRT-MICROSOFT-APNIC-SG",
    "address" : [ "One Microsft Way", "Redmond, WA 98052", "US" ],
    "street" : "One Microsft Way",
    "city" : "Redmond",
    "state" : "WA",
    "zip_code" : "98052",
    "country" : "US",
    "email" : [ "abuse@microsoft.com" ],
    "abuse_mailbox" : [ "abuse@microsoft.com" ],
    "admin_contacts" : [ "MP234-AP" ],
    "tech_contacts" : [ "MP234-AP" ],
    "remarks" : [ "abuse@microsoft.com is invalid" ],
    "mnt_by" : [ "MAINT-AP-MICROSOFT" ],
    "date_updated" : "2025-11-18",
    "source" : "APNIC"
  },
  "organization" : {
    "handle" : "ORG-MSPL4-AP",
    "name" : "Microsoft Singapore Pte. Ltd.",
    "address" : [ "One Microsoft Way" ],
    "street" : "Microsoft Way",
    "country" : [ "US" ],
    "email" : [ "dawn.bedard@microsoft.com" ],
    "phone" : [ "+011-425-706-8080" ],
    "fax_no" : [ "+011-425-936-7329" ],
    "mnt_ref" : [ "APNIC-HM" ],
    "mnt_by" : [ "APNIC-HM" ],
    "date_updated" : "2020-05-27",
    "source" : "APNIC"
  },
  "administrative_contacts" : [ {
    "handle" : "NK160-AP",
    "name" : "Naoki Kitajima",
    "address" : [ "Akasaka Garden City 4-15-1 Akasaka, Minato-ku, Tokyo 107-0052" ],
    "street" : "Akasaka",
    "city" : "Tokyo",
    "zip_code" : "107-0052",
    "country" : "JP",
    "email" : [ "naokikit@microsoft.com" ],
    "phone" : [ "+81-3-4512-3346" ],
    "fax_no" : [ "+81-3-4512-3416" ],
    "mnt_by" : [ "MAINT-AP-MSFT" ],
    "date_updated" : "2008-09-04",
    "source" : "APNIC"
  } ],
  "technical_contacts" : [ {
    "handle" : "NK160-AP",
    "name" : "Naoki Kitajima",
    "address" : [ "Akasaka Garden City 4-15-1 Akasaka, Minato-ku, Tokyo 107-0052" ],
    "street" : "Akasaka",
    "city" : "Tokyo",
    "zip_code" : "107-0052",
    "country" : "JP",
    "email" : [ "naokikit@microsoft.com" ],
    "phone" : [ "+81-3-4512-3346" ],
    "fax_no" : [ "+81-3-4512-3416" ],
    "mnt_by" : [ "MAINT-AP-MSFT" ],
    "date_updated" : "2008-09-04",
    "source" : "APNIC"
  } ],
  "abuse_contacts" : [ {
    "handle" : "AM2589-AP",
    "name" : "ABUSE MICROSOFTAPNICSG",
    "address" : [ "One Microsft Way", "Redmond, WA 98052", "US" ],
    "street" : "One Microsft Way",
    "city" : "Redmond",
    "state" : "WA",
    "zip_code" : "98052",
    "country" : "ZZ",
    "email" : [ "abuse@microsoft.com" ],
    "abuse_mailbox" : [ "abuse@microsoft.com" ],
    "phone" : [ "+000000000" ],
    "admin_contacts" : [ "MP234-AP" ],
    "tech_contacts" : [ "MP234-AP" ],
    "remarks" : [ "Generated from irt object IRT-MICROSOFT-APNIC-SG", "abuse@microsoft.com is invalid" ],
    "mnt_by" : [ "APNIC-ABUSE" ],
    "date_updated" : "2025-09-04",
    "source" : "APNIC",
    "addressCountry" : "US"
  } ]
}

Peers

AS Number	Description	Country
AS55410	Vodafone Idea Ltd. VIL	IN
AS6175	Cogent Communications, LLC	US
AS18084	Telstra International Limited	HK
AS9498	Bharti Airtel Limited	IN
AS136948	Today Vision	BD
AS4755	Tata Communications Limited	IN

Upstreams

AS Number	Description	Country
AS55410	Vodafone Idea Ltd. VIL	IN
AS9498	Bharti Airtel Limited	IN
AS4755	Tata Communications Limited	IN

Legacy Routes

2401:b640:17::/48