TCP IP Illustrated

This appendix does not cover the initialization that

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: al or nonlocal (Section 18.4), and whether directed broadcasts are forwarded or not (Section 12.3). Indeed, many operating characteristics of a given TCP/IP implementation can be modified by the system administrator. This appendix lists some of the configurable options for the various TCP/IP implementations that have been used throughout the text. As you might expect, every vendor does things differently from all others. Nevertheless, this appendix gives an idea of the types of parameters different implementations allow one to modify. A few options that are highly implementation specific, such as the low-water mark for the memory buffer pool, are not described. These variables are described for informational purposes only. Their names, default values, or interpretation can change from one release to the next. Always check your vendor's documentation (or bug them for adequate documentation) for the final word on these variables. This appendix does not cover the initialization that takes place every time the system is bootstrapped: the initialization of each network interface using ifconfig (setting the IP address, the subnet mask, etc.), entering static routes into the routing table, and the like. Instead, this appendix focuses on the configuration options that affect how TCP/IP operates. E.1 BSD/386 Version 1.0 This system is an example of the "classical" BSD configuration that has been used since 4.2BSD. Since the source code is distributed with the system, configuration options are specified by the administrator, and the kernel is recompiled. There are two types of options: constants that are defined in the kernel configuration file (see the config(8) manual page), and variable initializations in various C source files. Brave and knowledgeable administrators can also change the values of these C variables in either the running kernel or the kernel's disk image, using a debugger, to avoid rebuilding the kernel. Here are the constants that can be changed in the kernel's configuration file. IPFORWARDING The value of this constant initializes the kernel variable ipforwarding. If 0 (default), IP dat...
View Full Document

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.

Ask a homework question - tutors are online