Category Archives: computer networks

About RTO retransmission and tcp_orphan_retries

About RTO retransmission and tcp_orphan_retries tcp_orphan_retries – INTEGER This value influences the timeout of a locally closed TCP connection,when RTO retransmissions remain unacknowledged. source : Linux Kernel Documentation . 2.6.32 TYPICAL SHELL ON PROC FILESYSTEM [bash] $cat /proc/sys/net/ipv4/tcp_orphan_retries 0 $ [/bash] TYPICAL SOURCE CODE RELATED [c] net/ipv4/tcp_timer.c – 39 identical 99: static int tcp_orphan_retries(struct sock …

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when RTO retransmissions remain unacknowledged…

$cat /proc/sys/net/ipv4/tcp_orphan_retries 0 $ tcp_orphan_retries – INTEGER This value influences the timeout of a locally closed TCP connection, when RTO retransmissions remain unacknowledged. See tcp_retries2 for more details. The default value is 7 If your machine is a loaded WEB server, you should think about lowering this value, such sockets may consume significant resources. Cf. …

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About software port and related to service type micromuse-lm

ABOUT SOFTWARE PORT A Software Port (usually just called a ‘port’) is a virtual data connection that can be used by programs to exchange data directly, instead of going through a file or other temporary storage location. The most common of these are TCP and UDP ports which are used to exchange data between computers …

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wireshark and micromuse-lm

Frame 74388 (60 bytes on wire, 60 bytes captured) Ethernet II, Src: Netgear_b4:91:1a (00:1f:33:b4:91:1a), Dst: Giga-Byt_f2:71:b6 (00:1a:4d:f2:71:b6) Internet Protocol, Src: 209.85.231.100 (209.85.231.100), Dst: 10.0.0.2 (10.0.0.2) Transmission Control Protocol, Src Port: http (80), Dst Port: micromuse-lm (1534), Seq: 3405, Ack: 4005, Len: 0 Source port: http (80) Destination port: micromuse-lm (1534) Stream index: 222 Sequence number: …

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What is tcp_keepalive_probes ?

tcp_keepalive_probes the number of unacknowledged probes to send before considering the connection dead and notifying the application layer source : www.tldp.org $cat /proc/sys/net/ipv4/tcp_keepalive_probes 9 $ trunk/os/ip/tcp.c – 7 identical 2436: /* Compute usable segment based on offered window and limit 2437: * window probes to one 2438: */ 3064: return tcphangup(c); 30100: if(n >= 1 …

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number of unacknowledged probes TCP

tcp_keepalive_probes the number of unacknowledged probes to send before considering the connection dead and notifying the application layer source : www.tldp.org $cat /proc/sys/net/ipv4/tcp_keepalive_probes 9 $ trunk/os/ip/tcp.c – 7 identical 2436: /* Compute usable segment based on offered window and limit 2437: * window probes to one 2438: */ 3064: return tcphangup(c); 3065: if(n >= 1 …

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What does rfc 1337 say ?

From RFC 1337. TIME-WAIT state removes the hazard of old duplicates for “fast” or “long” connections, in which clock-driven ISN selection is unable to prevent overlap of the old and new sequence spaces. The TIME-WAIT delay allows all old duplicate segments time enough to die in the Internet before the connection is reopened. echo 1 …

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tcp tuning tcp_rfc1337

From RFC 1337. TIME-WAIT state removes the hazard of old duplicates for “fast” or “long” connections, in which clock-driven ISN selection is unable to prevent overlap of the old and new sequence spaces. The TIME-WAIT delay allows all old duplicate segments time enough to die in the Internet before the connection is reopened. echo 1 …

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nc – tcp/ip swiss army knife

ABOUT nc Netcat (often abbreviated to nc) is a computer networking utility for reading from and writing to network connections using TCP or UDP. Netcat is designed to be a dependable back-end that can be used directly or easily driven by other programs and scripts. At the same time, it is a feature-rich network debugging …

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