Committee T1  
   Sponsored by the Alliance for Telecommunications Industry Solutions and accredited by ANSI for interoperability standards.
   http://www.t1.org/

T1 T-extender  
   DCB's T1 repeater for customer-owned cable.
   http://www.dcbnet.com/datasheet/textds.html

DCB's T1 Info  
   All you wanted to know about T1's but were afraid to ask.
   http://www.dcbnet.com/notes/9611t1.html

Network and Services Integration Forum  
   Provides an open industry forum for the discussion and resolution of multiple technology integration and SONET interoperability issues.
   http://www.atis.org/atis/sif/sifhom.htm

SONET/SDH Technical Summary  
   Defines SONET and SDH, and provides references to appropriate standards organizations.
   http://www.techfest.com/networking/wan/sonet.htm

EverythingT1.com  
   Offering T-1/T-3 information, glossary, FAQs, reference, Technical reports, news, messageboard, ISP lists and links.
   http://www.everythingt1.com/

T-1 Carrier  
   Webopedia definition and links about T1.
   http://webopedia.com/TERM/T/T_1_carrier.html