ASN AS721 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS721?

AS721 is listed under United States Department of Defense.

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.

AS721 United States Department of Defense

United States Department of Defense war.gov

US 229 Routes

AS Data

AS721

AS721 – United States Department of Defense

AS Number	721
AS Name	DNIC-ASBLK-00721-00726
Organization	United States Department of Defense (usddd)
Country	US
Website	war.gov
Number of IPv4 Routes	227
Number of IPv6 Routes	2
ASN type	GOVERNMENT
Registry	ARIN
Date Allocated	N/A

ASN Intelligence API for production workflows

Use ASN data for AS721 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
199.211.176.0/20	AS721	United States Department of Defense	DoD Network Information Center	4096
199.209.0.0/16	AS721	United States Department of Defense	DoD Network Information Center	65536
131.16.0.0/16	AS721	United States Department of Defense	Air Force Systems Networking	65536
155.216.0.0/14	AS1540	U.S. Army Information Systems Command	U.S. Army Information Systems Command	262144
199.122.56.0/21	AS367	United States Department of Defense	U.S. Army Information Systems Command	2048
198.97.192.0/21	AS721	United States Department of Defense	United States Department of Defense DoD	2048
143.73.0.0/16	AS367	United States Department of Defense	U.S. Army Information Systems Command	65536
155.29.48.0/23	AS721	United States Department of Defense	U.S. Army Information Systems Command	512
146.55.124.0/24	AS721	United States Department of Defense	U.S. Army Information Systems Command	256
138.168.0.0/14	AS637	United States Department of Defense	MARINE CORPS CYBERSPACE OPERATIONS GROUP	262144
153.26.0.0/16	AS721	United States Department of Defense	Air Force Systems Networking	65536
147.216.0.0/15	AS721	United States Department of Defense	U.S. Army Information Systems Command	131072
158.236.0.0/14	AS637	United States Department of Defense	MARINE CORPS CYBERSPACE OPERATIONS GROUP	262144
143.69.0.0/16	AS721	United States Department of Defense	U.S. Army Information Systems Command	65536
199.252.155.0/24	AS721	United States Department of Defense	United States Department of Defense DoD	256
199.122.32.0/20	AS721	United States Department of Defense	U.S. Army Information Systems Command	4096
136.212.0.0/14	AS721	United States Department of Defense	DoD Network Information Center	262144
132.96.0.0/11	AS306	United States Department of Defense	United States Department of Defense DoD	2097152
139.244.2.0/24	AS721	United States Department of Defense	DoD Network Information Center	256
198.97.240.0/20	AS721	United States Department of Defense	DoD Network Information Center	4096
199.252.32.0/20	AS721	United States Department of Defense	United States Department of Defense DoD	4096
137.209.0.0/16	AS721	United States Department of Defense	DoD Network Information Center	65536
192.86.232.0/21	AS367	United States Department of Defense	United States Department of Defense DoD	2048
143.81.103.0/24	AS721	United States Department of Defense	U.S. Army Information Systems Command	256
160.132.0.0/15	AS1540	U.S. Army Information Systems Command	U.S. Army Information Systems Command	131072
199.123.72.0/21	AS1540	U.S. Army Information Systems Command	United States Department of Defense DoD	2048
199.123.91.0/24	AS721	United States Department of Defense	U.S. Army Information Systems Command	256
140.21.0.0/16	AS721	United States Department of Defense	DoD Network Information Center	65536
131.78.3.0/24	AS721	United States Department of Defense	DoD Network Information Center	256
158.0.0.0/13	AS721	United States Department of Defense	DoD Network Information Center	524288
215.65.0.0/18	AS721	United States Department of Defense	DoD Network Information Center	16384
209.22.0.0/16	AS721	United States Department of Defense	DoD Network Information Center	65536
140.13.73.0/24	AS721	United States Department of Defense	DoD Network Information Center	256
192.138.24.0/21	AS5972	United States Department of Defense	United States Department of Defense DoD	2048
207.132.0.0/15	AS721	United States Department of Defense	DoD Network Information Center	131072
55.0.0.0/8	AS721	United States Department of Defense	U.S. Army Information Systems Command	16777216
138.164.0.0/14	AS721	United States Department of Defense	DoD Network Information Center	262144
204.37.8.0/21	AS721	United States Department of Defense	United States Department of Defense DoD	2048
134.233.0.0/16	AS721	United States Department of Defense	U.S. Army Information Systems Command	65536
215.0.0.0/9	AS749	United States Department of Defense	DoD Network Information Center	8388608
144.104.0.0/15	AS721	United States Department of Defense	U.S. Army Information Systems Command	131072
131.86.0.0/15	AS27046	United States Department of Defense	DoD Network Information Center	131072
204.208.0.0/16	AS5972	United States Department of Defense	U.S. Army Information Systems Command	65536
131.74.0.0/15	AS721	United States Department of Defense	DoD Network Information Center	131072
199.32.128.0/18	AS721	United States Department of Defense	DoD Network Information Center	16384
156.112.148.0/23	AS27065	United States Department of Defense	DoD Network Information Center	512
199.251.0.0/16	AS721	United States Department of Defense	United States Department of Defense DoD	65536
143.212.0.0/15	AS1602	U.S. Army Information Systems Command	U.S. Army Information Systems Command	131072
199.252.154.0/24	AS721	United States Department of Defense	United States Department of Defense DoD	256
140.153.72.0/24	AS721	United States Department of Defense	U.S. Army Information Systems Command	256
199.252.180.0/24	AS721	United States Department of Defense	United States Department of Defense DoD	256
198.220.0.0/16	AS721	United States Department of Defense	Air Force Systems Networking	65536
137.8.0.0/14	AS721	United States Department of Defense	DoD Network Information Center	262144
199.252.143.0/24	AS721	United States Department of Defense	United States Department of Defense DoD	256
199.114.32.0/20	AS721	United States Department of Defense	U.S. Army Information Systems Command	4096
206.37.202.0/24	AS721	United States Department of Defense	DoD Network Information Center	256
192.153.144.0/21	AS721	United States Department of Defense	U.S. Army Information Systems Command	2048
199.252.162.0/24	AS721	United States Department of Defense	United States Department of Defense DoD	256
158.8.0.0/14	AS5180	United States Department of Defense	DoD Network Information Center	262144
138.160.0.0/15	AS721	United States Department of Defense	DoD Network Information Center	131072

Raw Whois Response

#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
#
# Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
#


ASNumber:       721 - 726
ASName:         DNIC-ASBLK-00721-00726
ASHandle:       AS721
RegDate:        
Updated:        2025-09-12
Ref:            https://rdap.arin.net/registry/autnum/721


OrgName:        United States Department of Defense (DoD)
OrgId:          USDDD
Address:        3990 E. Broad Street
City:           Columbus
StateProv:      OH
PostalCode:     43218
Country:        US
RegDate:        2007-01-12
Updated:        2026-08-12
Ref:            https://rdap.arin.net/registry/entity/USDDD


OrgNOCHandle: MIL-HSTMST-ARIN
OrgNOCName:   Network DoD
OrgNOCPhone:  +1-844-347-2457 
OrgNOCEmail:  disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil
OrgNOCRef:    https://rdap.arin.net/registry/entity/MIL-HSTMST-ARIN

OrgAbuseHandle: MIL-HSTMST-ARIN
OrgAbuseName:   Network DoD
OrgAbusePhone:  +1-844-347-2457 
OrgAbuseEmail:  disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil
OrgAbuseRef:    https://rdap.arin.net/registry/entity/MIL-HSTMST-ARIN

OrgTechHandle: REGIS10-ARIN
OrgTechName:   Registration
OrgTechPhone:  +1-844-347-2457 
OrgTechEmail:  disa.columbus.ns.mbx.arin-registrations@mail.mil
OrgTechRef:    https://rdap.arin.net/registry/entity/REGIS10-ARIN

OrgTechHandle: MIL-HSTMST-ARIN
OrgTechName:   Network DoD
OrgTechPhone:  +1-844-347-2457 
OrgTechEmail:  disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil
OrgTechRef:    https://rdap.arin.net/registry/entity/MIL-HSTMST-ARIN


#
# ARIN WHOIS data and services are subject to the Terms of Use
# available at: https://www.arin.net/resources/registry/whois/tou/
#
# If you see inaccuracies in the results, please report at
# https://www.arin.net/resources/registry/whois/inaccuracy_reporting/
#
# Copyright 1997-2026, American Registry for Internet Numbers, Ltd.
#

Parsed Whois Response

{
  "status" : true,
  "whois_server" : "whois.arin.net",
  "aut_nums" : [ {
    "aut_num" : "721 - 726",
    "as_handle" : "AS721",
    "as_name" : "DNIC-ASBLK-00721-00726",
    "tech_contacts" : [ "REGIS10-ARIN", "MIL-HSTMST-ARIN" ],
    "abuse_contacts" : [ "MIL-HSTMST-ARIN" ],
    "date_updated" : "2025-09-12",
    "source" : "https://rdap.arin.net/registry/autnum/721"
  } ],
  "organization" : {
    "handle" : "USDDD",
    "name" : "United States Department of Defense (DoD)",
    "address" : [ "3990 E. Broad Street", "Columbus", "OH", "43218", "US" ],
    "street" : "E. Broad Street",
    "city" : "Columbus",
    "state" : "OH",
    "zip_code" : "43218",
    "country" : [ "US" ],
    "date_created" : "2007-01-12",
    "date_updated" : "2026-08-12",
    "source" : "https://rdap.arin.net/registry/entity/USDDD",
    "addressCountry" : "US"
  },
  "technical_contacts" : [ {
    "handle" : "REGIS10-ARIN",
    "name" : "Registration",
    "email" : [ "disa.columbus.ns.mbx.arin-registrations@mail.mil" ],
    "phone" : [ "+1-844-347-2457" ],
    "source" : "https://rdap.arin.net/registry/entity/REGIS10-ARIN"
  }, {
    "handle" : "MIL-HSTMST-ARIN",
    "name" : "Network DoD",
    "email" : [ "disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil" ],
    "phone" : [ "+1-844-347-2457" ],
    "source" : "https://rdap.arin.net/registry/entity/MIL-HSTMST-ARIN"
  } ],
  "abuse_contacts" : [ {
    "handle" : "MIL-HSTMST-ARIN",
    "name" : "Network DoD",
    "email" : [ "disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil" ],
    "phone" : [ "+1-844-347-2457" ],
    "source" : "https://rdap.arin.net/registry/entity/MIL-HSTMST-ARIN"
  } ]
}

Peers

AS Number	Description	Country
AS27065	United States Department of Defense DoD	US
AS27064	United States Department of Defense DoD	US
AS27066	United States Department of Defense DoD	US
AS3356	Level 3 Parent, LLC	US

Upstreams

AS Number	Description	Country
AS3356	Level 3 Parent, LLC	US

Downstreams

AS Number	Description	Country
AS27065	United States Department of Defense DoD	US
AS27064	United States Department of Defense DoD	US
AS27066	United States Department of Defense DoD	US

Legacy Routes

140.14.51.0/24 140.14.47.0/24 140.14.45.0/24 140.14.35.0/24 140.14.53.0/24 140.14.49.0/24 140.14.41.0/24 140.14.37.0/24 140.14.43.0/24 140.14.39.0/24

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