Appendix A
Ethernet Network Parameters
Parameter | Value |
| Description |
|
|
|
|
TCP send buffer | 4,096 bytes |
| Maximum capacity of the TCP send buffer |
|
|
|
|
TCP receive buffer | 4,096 bytes |
| Maximum capacity of the TCP receive buffer |
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|
|
|
UDP send buffer | 9,000 bytes |
| Maximum capacity of the UDP send buffer |
|
|
|
|
UDP receive buffer | 9,016 bytes |
| Maximum capacity of the UDP receive buffer |
|
|
|
|
RAW send buffer | 2,048 bytes |
| Maximum capacity of the RAW send buffer |
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|
|
|
RAW receive buffer | 2,048 bytes |
| Maximum capacity of the RAW receive buffer |
|
|
|
|
FINS receive buffer | 16,383 bytes |
| Maximum capacity of the FINS receive buffer |
|
|
| |
Hold timer | 75 s (12 min max.) | The hold timer is used for active open processing of TCP sockets. A | |
|
|
| ETIMEDOUT error will occur if connection is not completed within 75 s. |
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|
|
|
Resend timer | Initial value: | 1 s | The resend timer is used to monitor completion of reception of arrival |
| Maximum value: 64 s | confirmations when transferring data via socket services, including FTP | |
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|
| server and mail transfer TCP sockets. If the timer setting is exceeded |
|
|
| before arrival confirmation is received, data is resent. Resends are per- |
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|
| formed from the first timeout (1 s) through the 12th timeout (64 s). A |
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|
| ETIMEDOUT error will occur after the 12th timeout. |
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|
|
Continue timer | Initial value: | 5 s | The continue timer starts if preparations have been completed to send |
| Maximum value: 60 s | data but the send window is too small (either 0 or too small) to send the | |
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| data and the remote node has not requested that communications be |
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|
| restarted. Confirmation of the window size is requested from the remote |
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| node when the continue timer times out. The initial value of the timer is |
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|
| 5 s and confirmation processing will continue consecutively with increas- |
|
|
| ingly longer times until the maximum time of 60 s is reached. |
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|
|
|
2MSL timer | 60 s |
| The 2MSL timer starts at the TCP socket that first closes the socket and |
|
|
| will run for 60 s in the TIME_WAIT status. |
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|
|
IP reassemble timer | 12 s |
| A fragmented IP packet is discarded if it cannot be reassembled within 12 |
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| seconds. |
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|
|
|
ARP timer | 20 min/3 min |
| 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 3 minutes. |
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|
|
Window size | 4,096 bytes |
| The initial value of the maximum capacity used to control the conver- |
|
|
| gence of TCP sockets. Actually, the node negotiates with the remote |
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| node and uses the smaller of the values for the two nodes. The window |
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| size will fluctuate with the available space in the TCP reception buffers of |
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| the remote node when processing communications. |
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|
|
Fragment size | 1,500 bytes |
| UDP data is separated into |
|
|
| 28 bytes are for the IP header. |
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|
|
|
Segment size | 1,024 bytes |
| TCP data is separated into |
|
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| ferent, in which case it will be separated into |
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|
|
TTL (Time to Live) | 30 |
| Decremented each time an IP router is passed. |
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