TCP IP Illustrated

Defines the maximum udp datagram that can be sent

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Unformatted text preview: of 500-ms clock ticks before sending a keepalive probe. Default value is 14400 (2 hours). tcp_keepintvl Number of 500-ms clock ticks between successive keepalive probes, when no response is received. Default value is 150 (75 seconds). file:///D|/Documents%20and%20Settings/bigini/Docu...homenet2run/tcpip/tcp-ip-illustrated/append_e.htm (4 of 16) [12/09/2001 14.48.06] Appendix E: Configurable Options udp_cksum If nonzero, UDP checksums are calculated for outgoing UDP datagrams, and incoming UDP datagrams containing nonzero checksums have their checksum verified. If 0, outgoing UDP datagrams do not contain a checksum, and no checksum verification is performed on incoming UDP datagrams, even if the sender calculated a checksum. Default is 0. udp_ttl The default value for the TTL field in UDP datagrams. Default value is 60. udp_sendspace The default size of the UDP send buffer. Defines the maximum UDP datagram that can be sent. Default is 9000. udp recvspace The default size of the UDP receive buffer. The default is 18000, allowing for two 9000-byte datagrams. E.3 System V Release 4 The TCP/IP configuration of SVR4 is similar to the previous two systems, but fewer options are available. In the file /etc/conf/pack.d/ip/space.c two constants can be defined, and the kernel must then be rebuilt and rebooted. IPFORWARDING The value of this constant initializes the kernel variable ipforwarding. If 0 (default), IP datagrams are not forwarded. If 1, forwarding is always enabled. IPSENDREDIRECTS The value of this constant initializes the kernel variable ipsendredirects. If 1 (default), the host will send ICMP redirects when forwarding IP datagrams. If 0, ICMP redirects are not sent. Many of the variables that we've described in the previous two sections are defined in the kernel, but one must patch the kernel to modify them. For example, there is a variable named tcp_keepidle with a value of 14400. E.4 Solaris 2.2 Solaris 2.2 is typical of the newer Unix systems that provide a program for the administrator to run to change the configuration options of the TCP/I...
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This test prep was uploaded on 04/04/2014 for the course ECE EL5373 taught by Professor Guoyang during the Spring '12 term at NYU Poly.

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