Dùng wireshark kiểm tra các gói tin thì cũng không biết lỗi ở chỗ nào, dưới đây là 2 gói SYN và SYN,ACK. Thầy xem giúp em có lỗi nào k ạ.
Code:
No. Time Source Destination Protocol Length Info
4 2.391813 192.168.1.3 192.168.1.2 TCP 74 39458 > http [SYN] Seq=0 Win=14600 Len=0 MSS=1460 SACK_PERM=1 TSval=3276993 TSecr=0 WS=16
Frame 4: 74 bytes on wire (592 bits), 74 bytes captured (592 bits)
Ethernet II, Src: AsustekC_30:80:a2 (f4:6d:04:30:80:a2), Dst: DavicomS_11:02:0f (01:60:6e:11:02:0f)
Internet Protocol Version 4, Src: 192.168.1.3 (192.168.1.3), Dst: 192.168.1.2 (192.168.1.2)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
Total Length: 60
Identification: 0xe8f7 (59639)
Flags: 0x02 (Don't Fragment)
Fragment offset: 0
Time to live: 64
Protocol: TCP (6)
Header checksum: 0xce6e [correct]
Source: 192.168.1.3 (192.168.1.3)
Destination: 192.168.1.2 (192.168.1.2)
Transmission Control Protocol, Src Port: 39458 (39458), Dst Port: http (80), Seq: 0, Len: 0
Source port: 39458 (39458)
Destination port: http (80)
[Stream index: 0]
Sequence number: 0 (relative sequence number)
Header length: 40 bytes
Flags: 0x02 (SYN)
Window size value: 14600
[Calculated window size: 14600]
Checksum: 0x8384 [validation disabled]
Options: (20 bytes)
Maximum segment size: 1460 bytes
TCP SACK Permitted Option: True
Timestamps: TSval 3276993, TSecr 0
Kind: Timestamp (8)
Length: 10
Timestamp value: 3276993
Timestamp echo reply: 0
No-Operation (NOP)
Window scale: 4 (multiply by 16)
0000 01 60 6e 11 02 0f f4 6d 04 30 80 a2 08 00 45 00 .`n....m.0....E.
0010 00 3c e8 f7 40 00 40 06 ce 6e c0 a8 01 03 c0 a8 .<..@.@..n......
0020 01 02 9a 22 00 50 d8 2c e8 36 00 00 00 00 a0 02 ...".P.,.6......
0030 39 08 83 84 00 00 02 04 05 b4 04 02 08 0a 00 32 9..............2
0040 00 c1 00 00 00 00 01 03 03 04 ..........
Code:
No. Time Source Destination Protocol Length Info
5 2.395242 192.168.1.2 192.168.1.3 TCP 62 http > 39458 [SYN, ACK] Seq=0 Ack=1 Win=2800 Len=0 MSS=1400 WS=1
Frame 5: 62 bytes on wire (496 bits), 62 bytes captured (496 bits)
Ethernet II, Src: DavicomS_11:02:0f (01:60:6e:11:02:0f), Dst: AsustekC_30:80:a2 (f4:6d:04:30:80:a2)
Internet Protocol Version 4, Src: 192.168.1.2 (192.168.1.2), Dst: 192.168.1.3 (192.168.1.3)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
Total Length: 48
Identification: 0x0000 (0)
Flags: 0x00
Fragment offset: 0
Time to live: 128
Protocol: TCP (6)
Header checksum: 0xb772 [correct]
Source: 192.168.1.2 (192.168.1.2)
Destination: 192.168.1.3 (192.168.1.3)
Transmission Control Protocol, Src Port: http (80), Dst Port: 39458 (39458), Seq: 0, Ack: 1, Len: 0
Source port: http (80)
Destination port: 39458 (39458)
[Stream index: 0]
Sequence number: 0 (relative sequence number)
Acknowledgement number: 1 (relative ack number)
Header length: 28 bytes
Flags: 0x12 (SYN, ACK)
Window size value: 2800
[Calculated window size: 2800]
Checksum: 0x6e24 [validation disabled]
Options: (8 bytes)
Maximum segment size: 1400 bytes
No-Operation (NOP)
Window scale: 0 (multiply by 1)
[SEQ/ACK analysis]
[This is an ACK to the segment in frame: 4]
[The RTT to ACK the segment was: 0.003429000 seconds]
0000 f4 6d 04 30 80 a2 01 60 6e 11 02 0f 08 00 45 00 .m.0...`n.....E.
0010 00 30 00 00 00 00 80 06 b7 72 c0 a8 01 02 c0 a8 .0.......r......
0020 01 03 00 50 9a 22 12 34 00 00 d8 2c e8 37 70 12 ...P.".4...,.7p.
0030 0a f0 6e 24 00 00 02 04 05 78 01 03 03 00 ..n$.....x....
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