1*f85d9c45SChia-Yu Chang// Test SYN/ACK rexmit triggered 3rd ACK duplicate + CE on first data seg 2*f85d9c45SChia-Yu Chang 3*f85d9c45SChia-Yu Chang`./defaults.sh 4*f85d9c45SChia-Yu Changsysctl -q net.ipv4.tcp_ecn=3 5*f85d9c45SChia-Yu Chang` 6*f85d9c45SChia-Yu Chang 7*f85d9c45SChia-Yu Chang 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 8*f85d9c45SChia-Yu Chang +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 9*f85d9c45SChia-Yu Chang +0 bind(3, ..., ...) = 0 10*f85d9c45SChia-Yu Chang +0 listen(3, 1) = 0 11*f85d9c45SChia-Yu Chang 12*f85d9c45SChia-Yu Chang +0 < SEWA 0:0(0) win 32792 <mss 1050,nop,nop,sackOK,nop,wscale 8> 13*f85d9c45SChia-Yu Chang+.002 > SW. 0:0(0) ack 1 <mss 1460,ECN e1b 1 ceb 0 e0b 1,nop,nop,nop,sackOK,nop,wscale 8> 14*f85d9c45SChia-Yu Chang 15*f85d9c45SChia-Yu Chang// SYN/ACK rexmitted => two 3rd ACKs in-flight 16*f85d9c45SChia-Yu Chang+1.0~+1.1 > SW. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8> 17*f85d9c45SChia-Yu Chang// Delivered 1st 3rd ACK 18*f85d9c45SChia-Yu Chang+0.05 < [ect0] W. 1:1(0) ack 1 win 257 <ECN e0b 1 ceb 0 e1b 1,nop> 19*f85d9c45SChia-Yu Chang+.002 accept(3, ..., ...) = 4 20*f85d9c45SChia-Yu Chang 21*f85d9c45SChia-Yu Chang// Duplicate 3rd ACK delivered 22*f85d9c45SChia-Yu Chang+1.05 < [ect0] W. 1:1(0) ack 1 win 257 <ECN e0b 1 ceb 0 e1b 1,nop> 23*f85d9c45SChia-Yu Chang 24*f85d9c45SChia-Yu Chang+0.05 < [ce] EAP. 1:1001(1000) ack 1 win 257 <ECN e0b 1 ceb 0 e1b 1,nop> 25*f85d9c45SChia-Yu Chang+.002 > [ect0] WA. 1:1(0) ack 1001 <ECN e1b 1 ceb 1000 e0b 1,nop> 26*f85d9c45SChia-Yu Chang +0 read(4, ..., 1000) = 1000 27