805
Appendix I
Ethernet Network Parameters
Parameter
Value
Description
Hold timer
18 s
The hold timer is used for active open processing of TCP sockets.
An ETIMEDOUT error will occur if connection is not completed within
18 s.
Resend timer
3 s
The resend timer is used to monitor completion of reception of arrival
confirmations when transferring data via socket services. If the timer set-
ting is exceeded before arrival confirmation is received, data is resent.
Resends are performed through the 12th timeout (3 s).
An ETIMEDOUT error will occur after the 12th timeout.
2MSL timer
120 s
The 2MSL timer starts at the TCP socket that first closes the socket and
will run for 120 s in the TIME_WAIT status.
ARP timer
20 min/5 s
If a complete ARP table entry (with an Ethernet address) is not referred
to for 20 minutes, it is removed from the table.
An incomplete ARP table entry (no response yet returned to the ARP
request) is removed from the table after 5 seconds.
Window size
2,144 bytes
The initial value of the maximum capacity used to control the conver-
gence of TCP sockets. Actually, the node negotiates with the remote
node and uses the smaller of the values for the two nodes. The window
size will fluctuate with the available space in the TCP reception buffers of
the remote node when processing communications.
Segment size (MSS)
536 bytes
TCP data is separated into 536-byte units
TTL (Time to Live)
30
30
Summary of Contents for CP1L-EL20DR-D
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Page 34: ...xxxiv Software Licenses and Copyrights 7...
Page 192: ...158 Trial Operation and Debugging Section 5 3...
Page 250: ...216 Automatic Clock Adjustment and Specifying Servers by Host Name Section 6 7...
Page 666: ...632 Trouble Shooting Section 11 7...
Page 696: ...662 Standard Models Appendix A...
Page 805: ...771 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 806: ...772 Connections to Serial Communications Option Boards Appendix F...
Page 836: ...802 PLC Setup Appendix G...
Page 838: ...804 TCP Status Transitions Appendix H...
Page 840: ...806 Ethernet Network Parameters Appendix I...
Page 842: ...808 Buffer Configuration CP1L EL EM Appendix J...
Page 844: ...810 Ethernet Specifications Appendix K...
Page 851: ...Index 817 work words 118 write protection 447...
Page 852: ...818 Index...
Page 854: ...820 Revision History...
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