Exhibit 21.1

SUBSIDIARIES OF THE REGISTRANT
Legal Name	Doing Business As	State or Other Jurisdiction of Incorporation or Organization
Black Box Corporation	Black Box Corporation	Delaware
ACS Communications, Inc.	ACS Communications, Inc.	Texas
ACS Dataline of the Northwest, Inc.	Black Box Network Services Black Box Network Services - West	Oregon
ACS Investors, LLC	ACS Investors, LLC	Delaware
ACS Dataline, LP	Black Box Network Services Black Box Network Services - West	Texas
ACS Partners, LLC	ACS Partners, LLC	Texas
ADS Telecom, Inc.	Black Box Network Services	Florida
B & C Telephone, Inc.	Black Box Network Services Black Box Network Services - Spokane	Washington
BBox Holding Company	BBox Holding Company	Delaware
Advanced Communications Corporation	Black Box Network Services - South Carolina	South Carolina
Advanced Network Technologies, Inc.	Black Box Network Services - California	California
American Telephone Wiring Company	Black Box Network Services - West Virginia Operations	West Virginia
Atimco Network Services, Inc.	Black Box Network Services - Western Pennsylvania Operations	Pennsylvania
Black Box Corporation of Pennsylvania	Black Box Network Services	Delaware
BB Technologies, Inc.	BB Technologies, Inc.	Delaware
Black Box A/S	Black Box A/S	Denmark
Black Box Canada Corporation	Black Box Canada Corporation	Canada
Black Box Comunicaciones, S.A.	Black Box Comunicaciones, S.A.	Spain
Black Box Datacom B.V.	Black Box Datacom B.V.	Netherlands
Black Box Deutschland GmbH	Black Box Deutschland GmbH	Germany
Black Box Netzwerk Service GmbH	Black Box Netzwerk Service GmbH	Germany
Black Box do Brasil Industria e Comercio Ltda.	Black Box do Brasil Industria e Comercio Ltda.	Brazil
Black Box France	Black Box France	France
Black Box GmbH	Black Box GmbH	Austria

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Exhibit 21.1

Legal Name	Doing Business As	State or Other Jurisdiction of Incorporation or Organization
Black Box Network Services AG	Black Box Network Services AG	Switzerland
Black Box Network Services Australia Pty Ltd	Black Box Network Services Australia Pty Ltd	Australia
Black Box Network Services New Zealand Limited	Black Box Network Services New Zealand Limited	New Zealand
Black Box Network Services India Private Limited	Black Box Network Services India Private Limited	India
Black Box Network Services Kabushiki Kaisha	Black Box Network Services Kabushiki Kaisha	Japan
Black Box Network Services Korea Limited	Black Box Network Services Korea Limited	Korea
Black Box Network Services NV	Black Box Network Services NV	Belgium
Black Box Network Services S.r.l.	Black Box Network Services S.r.l.	Italy
Black Box Network Services (UK) Limited	Black Box Network Services (UK) Limited Black Box Network Services (UK) Limited - Northern Ireland	England
Black Box P.R. Corp.	Black Box P.R. Corp.	Puerto Rico
Black Box LLC Holdings, Inc.	Black Box LLC Holdings, Inc.	Delaware
PS Technologies, LLC	Black Box Network Services Black Box Network Services - Western Operations	Maryland
PS Tech Video, LLC	Black Box Network Services	California
Black Box Network and Electrical Services, Inc.	Black Box Network and Electrical Services, Inc. Allcom Electric	New York
Black Box Network Services, Inc. - Government Solutions	Black Box Network Services, Inc. - Government Solutions	Tennessee
Black Box Ventures Holding Company	Black Box Ventures Holding Company	Delaware
Cable Consultants, Incorporated	Black Box Network Services - Atlanta	Georgia
Comm Line, Inc.	Black Box Network Services	Ohio
Communication Contractors, Inc.	Black Box Network Services - Chicago	Illinois
Datel Communications, Inc.	Black Box Network Services - Arizona	Arizona
Delaney Telecom, Inc.	Black Box Network Services	Pennsylvania
DESIGNet, Inc.	Black Box Network Services - San Jose	California

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Exhibit 21.1

Legal Name	Doing Business As	State or Other Jurisdiction of Incorporation or Organization
InnerWireless, Inc.	Black Box Network Services Black Box Network Services - Wireless	Delaware
Integrated Cabling Systems, Inc.	Integrated Cabling Systems, Inc.	Nebraska
Jet Line Communications, Inc.	Black Box Network Services - Dallas	Texas
BBC Acquisition, LLC	BBC Acquisition, LLC	Texas
FBS Communications, L.P.	Black Box Network Services - San Antonio	Texas
K & A Communications, Inc.	K & A Communications, Inc.	Missouri
Koncepts Communications of L.I., Corp.	Black Box Network Services - Tristate Operations	New York
LOGOS Communications Systems, Inc.	Black Box Network Services Black Box Network Services - Cleveland	Ohio
Michael Electric, Inc.	Black Box Network Services - New Jersey	New Jersey
Midwest Communications Technologies, Inc.	Black Box Network Services	Ohio
Midwest Electronics and Communications, Inc.	Black Box Network Services - Denver Operations	Colorado
R & D Services, Inc.	R & D Services, Inc.	Massachusetts
Teldata Corporation	Black Box Network Services - Tennessee	Tennessee
Telefuture Communications Ltd.	Black Box Network Services - New Rochelle Office	New York
Todd Communications, Inc.	Black Box Network Services - North Carolina	North Carolina
U.S. Premise Networking Services, Inc.	Black Box Network Services - MN	Minnesota
Black Box AB	Black Box AB	Sweden
Black Box Chile S.A.	Black Box Chile S.A.	Chile
Black Box de Mexico, S.A. de C.V.	Black Box de Mexico, S.A. de C.V.	Mexico
Black Box Finland OY	Black Box Finland OY	Finland
Black Box Network Services AB	Black Box Network Services AB	Sweden
Black Box Network Services Corporation	Black Box Network Services Corporation	Taiwan
Black Box Network Services (Dublin) Limited	Black Box Network Services (Dublin) Limited	Ireland
Black Box Network Services Puebla, S.A. de C.V.	Black Box Network Services Puebla, S.A. de C.V.	Mexico

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Exhibit 21.1

Legal Name	Doing Business As	State or Other Jurisdiction of Incorporation or Organization
Black Box Network Services SDN. BHD.	Black Box Network Services SDN. BHD.	Malaysia
Black Box Network Services Singapore Pte Ltd.	Black Box Network Services Singapore Pte Ltd.	Singapore
Black Box Norge AS	Black Box Norge AS	Norway
Black Box Services Reseaux Mediterranee	Black Box Services Reseaux Mediterranee	France
CBS Technologies Corp.	Black Box Network Services	New York
Consultoria en Redes, S.A. de C.V.	Consultoria en Redes, S.A. de C.V.	Mexico
J.C. Informatica Integral, S.A. de C.V.	J.C. Informatica Integral, S.A. de C.V.	Mexico
Mutual Telecom Services Inc.	Black Box Network Services	Delaware
Network Communications Technologies, Inc.	Black Box Network Services Black Box Network Services - Charlotte	North Carolina
Norstan, Inc.	Black Box Network Services	Minnesota
Norstan Canada Inc.	Norstan Canada Inc.	Minnesota
Norstan Canada, Ltd./Norstan Canada, Ltee	Black Box Network Services	Canada
Norstan Communications, Inc.	Black Box Network Services Black Box Network Services - Montana Black Box Network Services - Northeast	Minnesota
NextiraOne, LLC	Black Box Network Services Black Box Network Services - Illinois Black Box Network Services - Midwest Black Box Network Services - Northeast Black Box Network Services - Northwest Black Box Network Services - South	Delaware
Data Communications 2000, Inc.	Data Communications 2000, Inc.	California
Milgo Holdings Canada, LLC	Milgo Holdings Canada, LLC	Delaware
NextiraOne Canada ULC	NextiraOne Canada ULC	Canada
NextiraOne California L.P.	NextiraOne California L.P.	California
NXO Installation, LLC	NXO Installation, LLC	Delaware
NextiraOne Federal, LLC	Black Box Network Services Black Box Network Services - Federal	Delaware
Quanta Systems, LLC	Black Box Network Services - Federal Security Solutions	Delaware
NextiraOne New York, LLC	Black Box Network Services	Delaware

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Exhibit 21.1

Legal Name	Doing Business As	State or Other Jurisdiction of Incorporation or Organization
Vibes Technologies, Inc.	Black Box Resale Services	Minnesota
Norstan International, Inc.	Norstan International, Inc.	Minnesota
Nortech Telecommunications Inc.	Black Box Network Services - Elk Grove	Illinois
Nu-Vision Technologies, Inc.	Black Box Network Services	New York
Nu-Vision Technologies, LLC	Black Box Network Services Black Box Network Services - Oregon	New York
BCS II, LLC	BCS II, LLC	Delaware
Scottel Voice & Data, Inc.	Black Box Network Services Black Box Network Services - Pacific	California
UCI Communications LLC	Black Box Network Services	South Carolina

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