Routers: The IOS and Its User Interface

Before examining the IOS, a review of hardware and hardware terminology is useful. This
section of the book reviews common hardware details.

Most Cisco routers have a console and an auxiliary port. All Cisco routers have a console port,
which is meant for local administrative access, from an ASCII terminal or computer using a
terminal emulator. The auxiliary port, missing on a few models of Cisco routers, is intended for
asynchronous dial access from an ASCII terminal or terminal emulator; the auxiliary port is
often used for dial backup.
Each router has different types of memory as follows:


What makes Cisco IOS Debug commands so useful?

Cisco IOS Show commands can tell you many things about what is going on with your router or switch, but they can’t tell you everything. For example, Show commands cannot tell you when routes drop in or out of the routing table, why an ISDN line failed to connect, whether a packet really went out the router, or what ICMP error code was received. On the other hand, Cisco IOS Debug commands can tell you all these things, and more.
Besides providing more detailed information than what Show commands can provide, Debug commands have the benefit of providing information in “real time” (or dynamically). This is contrary to Show commands that just take a snapshot in time and display the results on your console (somewhat static results). This real-time difference can be very helpful in diagnosing problems.


IPv6 di Router Cisco

Kemampuan Router Cisco untuk bisa mendukung operasional IPv6 salah satunya versi IOS yang lebih baru dan umumnya sudah stable pada versi IOS 12.2 keatas, serta module supervisor engine (SUP) untuk cisco 6500 & 7600 untuk support ipv6 (Thx to Fjr)

Referensi dari web untuk IOS yang sudah support IPv6 adalah :
12.0S, 12.xT, 12.2S, 12.2 SB, 12.2SRA, 12.3, dan 12.4
Berikut list Seri Router yang sudah pernah dicoba IPv6 berikut IOS nya
- Router Cisco 7200 (IOS 12.2 T & 12.3)
- Router Cisco 3660 (IOS 12.2 T)
- Router Cisco 3640 (IOS 12.2 T)
Resources memory dan CPU juga perlu dipertimbangkan bila ingin mengembangkan dari Routing dasar ke Advance Routing (IGP & EGP).
Konfigurasi dasar IPv6 di Router Cisco :
1. Contoh Konfigurasi IPv6 Address di Interface Fisik & Sub Interface


Dedicated Servers and Peers

In some networks, a server computer is a server computer and nothing else.
It’s dedicated to the sole task of providing shared resources, such as hard
drives and printers, to be accessed by the network client computers. Such a
server is referred to as a dedicated server because it can perform no other
task besides network services.

Other networks take an alternative approach, enabling any computer on the
network to function as both a client and a server. Thus, any computer can
share its printers and hard drives with other computers on the network. And
while a computer is working as a server, you can still use that same computer
for other functions such as word processing. This type of network is called
a peer-to-peer network, because all the computers are thought of as peers,
or equals.


Servers and Clients

The network computer that contains the hard drives, printers, and other
resources that are shared with other network computers is called a server.
This term comes up repeatedly, so you have to remember it. Write it on the
back of your left hand.

Any computer that’s not a server is called a client. You have to remember this
term, too. Write it on the back of your right hand.
Only two kinds of computers are on a network: servers and clients. Look at
your left hand and then look at your right hand. Don’t wash your hands until
you have these terms memorized.
The distinction between servers and clients in a network has parallels in
sociology — in effect, a sort of class distinction between the “haves” and
“have-nots” of computer resources:
 Usually, the most powerful and expensive computers in a network are
the servers. There’s a good technical reason: Every user on the network
shares the server’s resources.
 The cheaper and less powerful computers in a network are the clients.
Clients are the computers used by individual users for everyday work.
Because clients’ resources don’t have to be shared, they don’t have to
be as fancy.
 Most networks have more clients than servers. For example, a network
with ten clients can probably get by with one server.
 In many networks, a clean line of demarcation exists between servers
and clients. In other words, a computer functions as either a server or a
client, and not both. For the sake of an efficient network, a server can’t
become a client, nor can a client become a server.
 Other (usually smaller) networks can be more even-handed, allowing
any computer in the network to be a server and client at the same time.


What Is a Network?

A network is nothing more than two or more computers connected by a
cable (or in some cases, by a wireless connection) so that they can exchange
Of course, computers can exchange information in other ways besides networks.
Most of us have used what computer nerds call the sneakernet. That’s
where you copy a file to a diskette and then walk the disk over to someone
else’s computer. (The term sneakernet is typical of computer nerds’ feeble
attempts at humor, and why not? As a way to transfer information, sneakernet
was pretty feeble.)


Pengenalan cisco


Anda dapat memikirkan suatu router Cisco sebagai tujuan khusus komputer. Ia memiliki sistem operasi sendiri, yang disebut Internetwork Operating System (IOS), serta file dan filesystem. Jadi kita akan mulai dengan pembahasan tentang fungsi-fungsi administrasi sistem dasar bahwa sebuah router insinyur harus tampil. Ini mencakup pengelolaan router Anda filesystem, upgrade sistem operasi, melakukan backup, dan memulihkan konfigurasi sistem.

Cisco router menggunakan flash memory, bukan disk, untuk menyimpan informasi. Media penyimpanan flash secara signifikan lebih mahal dan lebih lambat dari disk penyimpanan, tetapi jumlah penyimpanan yang diperlukan untuk menjalankan sebuah router yang relatif kecil dibandingkan dengan jumlah yang dibutuhkan untuk menjalankan sebuah komputer untuk keperluan umum. Flash juga memiliki manfaat penting bahwa ia cenderung lebih bisa diandalkan daripada penyimpanan disk.