Snoop, however, has its own limitations. First, it requires a snoop proxy in the base station. Also, if the TCP sender is the mobile, the TCP code must be modified to respond to Explicit Loss Notification (ELN) packets from the base station.
Saverio Mascolo, Politecnico Di Bari, Claudio Casetti, Politecnico Di Torino, Mario Gerla, M. Y. Sanadidi, and Ren Wang
"TCP Westwood: Bandwidth Estimation for Enhanced Transport over Wireless Links"
TCP Westwood+, in contradiction to the initial version of Westwood, computes one sample of available bandwidth every RTT using all data acknowledged in the specific RTT, therefore obtaining more accurate estimates (Fig. 6a). However, from the perspective of real-time delivery, Westwood+’s efficiency is not evident, since it delivers a considerable amount of delayed packets (Fig. 6d). Inline with our analytical approach, reaching the downlink capacity (i.e. flows 30–50) maximizes transmission time T(n) and results in variable transmission periods which impact video delivery. The protocol responds inappropriately to the variation in the rate of arriving ACKs, since the disturbed inter-ACK spacing reflects the fluctuations in the receiving rate, due to congestion incidents.
Vassilis Tsaoussidis, Panagiotis Papadimitriou
"On TCP performance over asymmetric satellite links with real-time constraints"
TCPW나 TCPW+의 단점은 명확하지가 않네...
Saverio Mascolo, Politecnico Di Bari, Claudio Casetti, Politecnico Di Torino, Mario Gerla, M. Y. Sanadidi, and Ren Wang
"TCP Westwood: Bandwidth Estimation for Enhanced Transport over Wireless Links"
TCP Westwood+, in contradiction to the initial version of Westwood, computes one sample of available bandwidth every RTT using all data acknowledged in the specific RTT, therefore obtaining more accurate estimates (Fig. 6a). However, from the perspective of real-time delivery, Westwood+’s efficiency is not evident, since it delivers a considerable amount of delayed packets (Fig. 6d). Inline with our analytical approach, reaching the downlink capacity (i.e. flows 30–50) maximizes transmission time T(n) and results in variable transmission periods which impact video delivery. The protocol responds inappropriately to the variation in the rate of arriving ACKs, since the disturbed inter-ACK spacing reflects the fluctuations in the receiving rate, due to congestion incidents.
Vassilis Tsaoussidis, Panagiotis Papadimitriou
"On TCP performance over asymmetric satellite links with real-time constraints"
TCPW나 TCPW+의 단점은 명확하지가 않네...
