primary ip address

Hey Hey,

First off... let me just say who decided that Internet and internet would mean different things and why in 6+ years of school with IT related courses have I never heard of this before? Is this something that the occasional egghead pulls outta their ass or am I just oblivious?

Anyways... Let's exame what we're given to work with for this book

Quote:

Multihomed
A router, by definition, has two or more network interface layers (since it connects two or more networks).
Any system with multiple interfaces is called multihomed. A host can also be multihomed but unless it
specifically forwards packets from one interface to another, it is not called a router. Also, routers need not be
special hardware boxes that only move packets around an internet. Most TCP/IP implementations allow a
multihomed host to act as a router also, but the host needs to be specifically configured for this to happen. In
this case we can call the system either a host (when an application such as FTP or Telnet is being used) or a
router (when it's forwarding packets from one network to another). We'll use whichever term makes sense
given the context.

Quote:

Internet Addresses
Every interface on an internet must have a unique Internet address (also called an IP address). These
addresses are 32-bit numbers. Instead of using a flat address space such as 1, 2, 3, and so on, there is a
structure to Internet addresses.
These 32-bit addresses are normally written as four decimal numbers, one for each byte of the address. This
is called dotted-decimal notation. For example, the class B address of the author's primary system is
140.252.13.33.
The easiest way to differentiate between the different classes of addresses is to look at the first number of a
dotted-decimal address.

It is worth reiterating that a multihomed host will have multiple IP addresses: one per interface.
Since every interface on an internet must have a unique IP address, there must be one central authority for
allocating these addresses for networks connected to the worldwide Internet. That authority is the Internet
Network Information Center, called the InterNIC. The InterNIC assigns only network IDs. The assignment
of host IDs is up to the system administrator.

There are three types of IP addresses: unicast (destined for a single host), broadcast (destined for all hosts on
a given network), and multicast (destined for a set of hosts that belong to a multicast group).

Quote:

The Internet
In Figure 1.3 we showed an internet composed of two networks - an Ethernet and a token ring. In Sections
1.4 and 1.9 we talked about the worldwide Internet and the need to allocate IP addresses centrally (the
InterNIC) and the well-known port numbers (the IANA). The word internet means different things
depending on whether it's capitalized or not.
The lowercase internet means multiple networks connected together, using a common protocol suite. The
uppercase Internet refers to the collection of hosts (over one million) around the world that can communicate
with each other using TCP/IP. While the Internet is an internet, the reverse is not true.

Quote:

The Question
1.5 If you have an account on a host that is connected to a TCP/IP internet, what is its primary IP address? Is
the host connected to the worldwide Internet? Is it multihomed?

The author has actually published several books.. and I'm not sure how.. I think he's on crack.. I've even checked the Errata (typo's and corrections) which goes up to a 14th edition (1998) and there's no fix for this problem..

I would have still stuck with the fact that it want's something to do with RFC 1918 addressing, except that in the entire introduction (and also in his 3rd chapter on IP) there's no mention of Private addresses... he's even got an RFC section in the introduction.. and it's not mentioned..

Answer:
Primary IP Address: a unique unicast address?? That's about as close as you could get to answering this question
Is it on the Internet: Possibly
Is it multihomed: If it's on the Internet and routing between the Internet and internet..

I wouldn't even give this book to my lil sister as an intro to computers.. It's completely bogus... The tutorials on AO comprise a better networking book than this POS.

Peace,
HT