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AS54121 David M. Schwarz Architects, Inc.

Q: Why is WHOIS data shown for an ASN?

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

ASN Lookup Tool

David M. Schwarz Architects, Inc. dmsas.com

US 1 Routes

AS Data

AS54121

AS54121 – David M. Schwarz Architects, Inc.

AS Number	54121
AS Name	DMSAS
Organization	David M. Schwarz Architects, Inc. (dmsa)
Country	US
Website	dmsas.com
Number of IPv4 Routes	1
Number of IPv6 Routes	0
ASN type	BUSINESS
Registry	ARIN
Date Allocated	2011-10-07

ASN Intelligence API for production workflows

Use ASN data for AS54121 in automation: routing intelligence, peering analysis, ownership checks, and network observability.

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IP Ranges

Route	Origin	Origin Name	ISP	# IPs
205.157.136.0/24	AS54121	David M. Schwarz Architects, Inc.	David M. Schwarz Architectural Services	256

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:       54121
ASName:         DMSAS
ASHandle:       AS54121
RegDate:        2011-10-07
Updated:        2012-03-02
Comment:        http://www.dmsas.com
Ref:            https://rdap.arin.net/registry/autnum/54121


OrgName:        David M. Schwarz Architects, Inc.
OrgId:          DMSA
Address:        1707 L Street, NW
Address:        suite 400
City:           Washington
StateProv:      DC
PostalCode:     20036
Country:        US
RegDate:        2011-10-03
Updated:        2011-10-03
Comment:        http://www.dmsas.com
Ref:            https://rdap.arin.net/registry/entity/DMSA


OrgAbuseHandle: HOUSE11-ARIN
OrgAbuseName:   Houseknecht, Ted 
OrgAbusePhone:  +1-202-862-0777 
OrgAbuseEmail:  ted@dmsas.com
OrgAbuseRef:    https://rdap.arin.net/registry/entity/HOUSE11-ARIN

OrgTechHandle: HOUSE11-ARIN
OrgTechName:   Houseknecht, Ted 
OrgTechPhone:  +1-202-862-0777 
OrgTechEmail:  ted@dmsas.com
OrgTechRef:    https://rdap.arin.net/registry/entity/HOUSE11-ARIN

OrgNOCHandle: HOUSE11-ARIN
OrgNOCName:   Houseknecht, Ted 
OrgNOCPhone:  +1-202-862-0777 
OrgNOCEmail:  ted@dmsas.com
OrgNOCRef:    https://rdap.arin.net/registry/entity/HOUSE11-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" : "54121",
    "as_handle" : "AS54121",
    "as_name" : "DMSAS",
    "tech_contacts" : [ "HOUSE11-ARIN" ],
    "abuse_contacts" : [ "HOUSE11-ARIN" ],
    "date_created" : "2011-10-07",
    "date_updated" : "2012-03-02",
    "source" : "https://rdap.arin.net/registry/autnum/54121"
  } ],
  "organization" : {
    "handle" : "DMSA",
    "name" : "David M. Schwarz Architects, Inc.",
    "address" : [ "1707 L Street, NW", "suite 400", "Washington", "DC", "20036", "US" ],
    "street" : "L Street Nw",
    "city" : "Washington",
    "state" : "DC",
    "zip_code" : "20036",
    "country" : [ "US" ],
    "date_created" : "2011-10-03",
    "date_updated" : "2011-10-03",
    "source" : "https://rdap.arin.net/registry/entity/DMSA",
    "addressCountry" : "US"
  },
  "technical_contacts" : [ {
    "handle" : "HOUSE11-ARIN",
    "name" : "Houseknecht, Ted",
    "email" : [ "ted@dmsas.com" ],
    "phone" : [ "+1-202-862-0777" ],
    "source" : "https://rdap.arin.net/registry/entity/HOUSE11-ARIN"
  } ],
  "abuse_contacts" : [ {
    "handle" : "HOUSE11-ARIN",
    "name" : "Houseknecht, Ted",
    "email" : [ "ted@dmsas.com" ],
    "phone" : [ "+1-202-862-0777" ],
    "source" : "https://rdap.arin.net/registry/entity/HOUSE11-ARIN"
  } ]
}

Peers

AS Number	Description	Country
AS3356	Level 3 Parent, LLC	US

Upstreams

AS Number	Description	Country
AS3356	Level 3 Parent, LLC	US

Frequently Asked Questions

What is ASN AS54121?

ASN AS54121 is an Autonomous System Number used to identify a network for BGP internet routing.

Who manages ASN AS54121?

AS54121 is listed under David M. Schwarz Architects, Inc..

What do peers, upstreams, and downstreams mean?

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 included here?

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

How can I access full ASN table data?

This page previews large ASN datasets. Use See more to load additional rows, and upgrade your plan to view complete peer, route, upstream, and downstream data.