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Network Programming 
C++ Network Programming, Vol 2: Systematic Reuse with ACE and Frameworks (D. Schmidt, et al) [PPT] [Vol 1]
UNIX Network Programming with TCP/IP (Alan Dix) Beej's Guide to Unix Network Programming [Mirror]
Lecture Notes for Computer Network Programming Scalable Network Programming
UNIX Socket FAQ [Mirror] [Mirror] [Mirror] Introduction to Socket Programming [Mirror]
Programming UNIX Sockets in C FAQ (by Vic Metcalfe, et al) [Mirror] [Mirror]
Windows Sockets: A Quick And Dirty Primer Winsock Programmer's FAQ
Windows Sockets: An Open Interface for Network Programming under Microsoft Windows
Internet Programming Crash Course Programming with Sockets