4
Note that while you are allowed to print out the online version, you may not run the O'Reilly book through a photocopier, much less sell any of its (hypothetical) copies.
5
The original spirit of which (see above) still shows on some occasions in Europe.
6
The shell is a command-line interface to the Unix operating system. It's similar to the DOS prompt in a Microsoft Windows environment, albeit much more powerful.
7
The Ethernet FAQ at http://www.faqs.org/faqs/LANs/ethernet-faq/ talks about this issue, and a wealth of detailed historical and technical information is available at Charles Spurgeon's Ethernet web site at http://wwwhost.ots.utexas.edu/ethernet/.
8
Alan can be reached at [email protected]
9
NCP is the protocol on which Novell file and print services are based.
10
We will come back to this topic in Chapter 12, Important Network Features.
11
There have been commercial Unix systems (that you have to pay lots of money for) that came with a setuid-root shell script, which allowed users to gain root privilege using a simple standard trick.
12
In 1988, the RTM worm brought much of the Internet to a grinding halt, partly by exploiting a gaping hole in some programs including the sendmail program. This hole has long since been fixed.
13
The version of the Internet Protocol most frequently used on the Internet is Version 4. A lot of effort has been expended in designing a replacement called IP Version 6. IPv6 uses a different addressing scheme and larger addresses. Linux has an implementation of IPv6, but it isn't ready to document it in this book yet. The Linux kernel support for IPv6 is good, but a large number of network applications need to be modified to support it as well. Stay tuned.
14
Frequently, IP addresses will be assigned to you by the provider from whom you buy your IP connectivity. However, you may also apply to the NIC directly for an IP address for your network by sending email to [email protected], or by using the form at http://www.internic.net/.
15
Autonomous systems are slightly more general. They may comprise more than one IP network.
16
The cost of a route can be thought of, in a simple case, as the number of hops required to reach the destination. Proper calculation of route costs can be a fine art in complex network designs.
17
IRQs 2 and 9 are the same because the IBM PC design has two cascaded interrupt processors with eight IRQs each; the secondary processor is connected to IRQ 2 of the primary one.
