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Selective Acknowledgment (SACK) represents a critical enhancement to the Transmission Control Protocol (TCP) that significantly improves performance in networks experiencing packet loss. Unlike traditional cumulative acknowledgments, SACK allows receivers to inform senders about all successfully received segments, enabling more efficient retransmission strategies. This survey examines various TCP versions and variants that incorporate SACK mechanisms, analyzing their congestion control algorithms, performance characteristics, and suitability for different network environments, particularly in heterogeneous wired-cum-wireless networks. The evolution of SACK-based TCP variants demonstrates a progressive refinement in addressing the challenges posed by random errors in wireless links while maintaining robust congestion control in wired networks. Through comprehensive analysis of established and emerging TCP variants, this survey illuminates the path toward more adaptive and intelligent transport protocols capable of meeting the demands of modern heterogeneous network infrastructures.