My Top 10 Study Tips for Cisco's 640-607 CCNA Exam Our author offers her favorite tips and links for preparing for this popular Cisco exam.
by Karen Robertson-Kidd May 2003
The 640-607 Cisco Certified Network Associate (CCNA) exam is for techs who
want to prove they have the skills to run networks in small business environments.
Anyone with these letters after their name announces to the world that they
are well on their way to mastering Cisco's networking technologies. Before you
rush headlong into the exam, consider these 10 tips to help focus your studies.
Tip #1: Know the Exam
And I don't mean know the answers (though that would certainly help). I mean
know what you're up against. Cisco is more than a little clear about what you
can expect. Your first stop should be here:
http://www.cisco.com/warp/public/10/wwtraining/certprog/testing/current_exams/640-607.html
This link takes you to the CCNA objectives. It also gives some other crucial
bits of information. Here's where you find out you'll have 75 minutes to complete
45 to 55 questions (how many you get will depend on difficulty and other factors).
This is only a small portion of what Cisco reveals about this exam. Passing
the CCNA means you have what Cisco calls "apprentice knowledge" of
LAN, WAN, and dial access services installation, configuration and operation
on networks of no more than 100 nodes. A tech with CCNA certification will also
know the concepts for configuration and troubleshooting and understand the fundamentals
of Access Lists, IP, RIP, IGRP, VLANs, Serial, Frame Relay and Ethernet.
Be careful of one sentence in the objectives: "The following topics are
general guidelines for the content likely to be included on the CCNA exam. However,
other related topics may also appear on any specific delivery of the exam."
In other words, just because it's not specifically listed in the objectives,
don't assume you won't see it.
Now take a good long look at this:
http://www.cisco.com/warp/public/10/wwtraining/certprog/testing/simulation/tutorial.html
This is Cisco's CCNA demo, complete with examples of questions you'll see.
Most of the questions on the exam will be multiple choice, but you can also
expect to see matching, fill in the blank and -- the real bugbear of the 607
-- simulation questions.
It is the simulation portion of the exam that puts a chill into the heart of
every would-be CCNA, as well it should. While you might be able to memorize
concepts without understanding them -- perhaps even enough to fake your way
through the multiple-choice questions -- the simulations are designed to make
sure you know how to configure routers and switches. It's the difference between
studying and knowing.
Another useful resource is this TCPMag.com exam review by Andy Barkl:
http://www.tcpmag.com/archives/article.asp?EditorialsID=152
He walks you through much of the material you're going to have to understand
in order to start your preparations.
Once you know what you're up against on the CCNA, it's time to get started.
Tip #2: Gather Study Material
You don't need to break the bank to do it. A book or two would be a great start.
My recommendations are Wendell Odom's Cisco
CCNA Exam #640-607 Certification Guide and Todd Lammle's CCNA:
Cisco Certified Network Associate Study Guide Exam 640-607.
You can also find a wide variety of excellent resources online -- much of it
for free.
For example, Celtic
Rover recently hit the Web. This site offers study material, practice exams
and an excellent router simulator referred to as "the Machine." It's
one of the best CCNA study resources available online, and it is free.
Other excellent online resources include the "online gossip rag and rumor
mill for Cisco professionals" Router
God and "the learning lounge where the drinks are free," Cisco
Lounge.
Just remember, Google is your best bud. Webopedia
and Whatis are good friends as well.
Tip #3: Look Over the "Official" Stuff
Even with the free stuff, you should study the "official" Cisco recommendations.
These fall into one of three categories:
- Cisco Learning Partners:
It's here that Cisco clearly details the benefits you'll receive. This also
is where you may register for a course, if you choose not to go the self-study
route.
- Cisco's Networking
Academy Program: This is Cisco's comprehensive, global e-learning program.
Here's where you can find online instructor-led training, following Cisco's
IT curricula. The Network Academy Program offers the all-important hands-on
labs, which is really the only legitimate way to pass the CCNA. That hands-on
experience will serve you well in your career too.
- Cisco Press: Cisco offers a good many of its own study products.
If you're going to buy study material (and for heaven's sake, don't ignore
the free material available), you should at least stop here when you go shopping.
After all, this material comes from the "horse's mouth" since most
Cisco Press authors also work for Cisco.
Tip #4: Lay Hands on a Router or Router Sim
Preferably you should purchase a real router, but these don't come cheap. eBay
is an excellent source, though which router to get is a matter of debate. For
instance, one of the 2500 series routers would do very well for a home study
network but any Cisco router that is configurable and runs the Cisco IOS (no,
your cable router doesn't count) would do the trick. And, yes, what you learn
for the CCNA will help you on a network with non-Cisco routers; but, no, don't
study for the CCNA on a non-Cisco router. For the exam, stick to the real thing.
If you can't afford a router, a simulator is the next best thing. As I mentioned
earlier, you'll find a free one available at Celtic Rover. I might even argue
that since you actually face a router simulator on the exam, you'll have a better
feeling for what the exam's sim questions will be like if you go this route.
Right along with the IOS commands, learn the Cisco Access Control Lists (ACLs)
and frame types (yes, you can expect to see IPX on the exam. And so far as the
CCNA is concerned, NetWare 4.x is still the latest thing; no TCP/IP on Novell.
Know the basic encapsulations on a Cisco router: novell-ether, sap, snap, and
arpa). Know the protocols (ie, RIP vs OSPF) and when to use them. Know the three
routing protocol types (distance vector, link state, and hybrid). Know the routed
protocols IP and IPX inside and out. And know the parts of that router (if you're
studying with a real router, you can't help but learn this). Know the console
port from the auxiliary from the Ethernet from the serial from the modular.
Here are some links to help out with router commands:
And ACLs:
Tip #5: Eat, Breathe and Sleep the OSI Model
Cisco puts an interesting amount of emphasis on the OSI layered reference model
for the CCNA exam, in large part because it's the industry standard way of teaching
and understanding the networking process. It's far from perfect (just watch
debates flare up over the layers at which ARP and NICs function ), but it is
something you'd better know on this exam. Here's a chart I put together that
may help in your understanding.
OSI Model
| Layer # |
Layer Name |
Header |
Protocols/Services |
Remember This |
| 7 |
Application
(All)
|
Protocol Data Unit |
Telnet, FTP, SMTP,
HTTP, File and Print, Email, (WWW), EDI. |
Where the user requests
network services. This is not the application, as in a program. This is
database and application services. |
| 6 |
Presentation
(People)
|
Protocol Data Unit |
ASCII, EBCDIC, TIFF,
JPEG, GIF, PICT, MIDI, MPEG, QuickTime |
Decides how data is
represented and translated. Data is formatted for "presentation"
to the layers above and below. Encryption, compression and translation take
place here. |
| 5 |
Session
(Seem)
|
Protocol Data Unit |
RPC, ZIP, SCP, SQL,
X Window, NetBIOS, NFS, ASP, DNA SCP |
Establishes, maintains
and manages communication sessions between computers. Dialog control occurs
here. |
| 4 |
Transport
(To)
|
Segments |
TCP, NBP, UDP, NCP,
SPX, ADP, Windowing, flow control, synchronization |
Provides reliable data
segment transmission. Sets the stage for data disassembly and assembly,
before and after transmission. Remember: end-to-end connectivity. |
| 3 |
Network
(Need)
|
Datagrams or Packets |
IP, IPX, BootP, DHCP,
ICMP, BGP, OSPF, RIP. |
If it has anything
to do with routing, this is where it happens. This layer determines how
data will be routed across a network. Structure and logical (IP) addressing
occurs at this layer. Routers operate here. |
| 2 |
Data LinkSublayers
are MAC and LLC
(Data)
|
Frames |
MAC, LLC,
Frame Relay, LAPB, PPP, calculating CRC or FCS, controls access to the physical
medium. |
This layer
is concerned with the links and mechanisms that move data. Topology (Ethernet
or Token Ring) is defined here. Switches (generally) and all bridges operate
here. Remember: Framing. |
| 1 |
Physical
(Processing)
|
Bits (1s
and 0s) |
Ethernet,
Token Ring, HSSI, 802.3, bit synchronization, physical connector specifications.
|
If it's
on a network and you can touch it, it's here. This layer handles the electrical
and physical specifications for network media that carry data bits across
a network. Hubs, repeaters and multiplexors operate here. |
red = upper levels, blue = lower levels
In addition to the above chart, there are a number of resources available online
to help you understand and learn the OSI model. They include:
Tip #6: Keep the Hardware Straight
Your days of mindlessly plugging a patch cable into the wall's RJ-45 outlet
ended when you started down the CCNA path. For the exam, you'll need to know
the patch cable plugs into the outlet, which leads into the larger patch panel
in the server room and beyond that as well. You'll need to know the patch cable's
place in the greater scheme of the network. With that in mind, make sure you
understand the following:
- Network Interface Cards (NICs): There's a tremendous debate over
whether these are devices that work at Layer 1 (by virtue of passing on bits
into the network stream) or Layer 2 (for holding the Media Access Control
-- MAC -- address and the software drivers) . Don't get caught up in this
debate when you take the exam. As far as Cisco is concerned, NICs operate
at Layer 1 of the OSI Model. Period.
- Repeaters, Multiplexors and Hubs: Aside from sneakernet and two computers
connected by a crossover, some of the simplest networks you'll ever encounter
will use any or all of these simple devices. For the CCNA, know that they
operate at Layer 1 of the OSI Model. About hubs in particular, know that all
transmissions going into a hub through one port are rebroadcast out all the
other ports; know the difference between passive, active hubs and intelligent
hubs and that Token Ring hub is a Multistation Access Unit (MAU).
- Bridges: These devices operate at Layer 2 of the OSI Model because
they forward traffic based on MAC addresses. They connect two segments of
a network and isolate and contain collision domains within a segment.
- Switches: When you begin discussing switches, you start talking about
Spanning Tree Protocol. You should get to know that protocol very well. Also,
know that switches generally operate at Layer 2 of the OSI model. Know that
switches, unlike hubs, make direct connections between a transmitting device
and receiving device. This means a switch saves bandwidth, compared to a hub,
because it doesn't send signals to devices that don't need to receive the
signal. Switches generally use Layer 2 MAC addresses to switch traffic. Notice,
I keep saying generally. (Warning: Confusion ahead.) An
animal called a Layer 3 switch forwards traffic using Layer 3 IP addresses.
These are often are preferable to routers because they don't experience the
latency that routers do. You may see them in life, but they do not exist on
the CCNA.
- Routers: Routers operate at Layer 3 because they forward traffic
based on IP network numbers. Routers can create and connect several logical
networks. Routers can connect two different network topologies and provide
multiple paths between segments. The biggie to remember here is that routers,
by default, don't forward broadcasts. Routers divide broadcast domains.
- Wireless: Don't expect to see wireless technology on the CCNA; it
just isn't there. This doesn't mean you shouldn't know the basics. For instance,
Wireless Access Points don't communicate with each other but, in general,
with wireless clients. Wireless networks aren't secure because hackers need
only tap into the signal. For this reason, wireless is still more often used
on home networks than in business settings, though it is more expensive than
traditional networks. Wireless networks are, however, simpler to set up (all
those cables are gone); computers are more easily relocated within a network;
and it's often very fast (for instance, WiFi currently offers speeds of up
to 5Mbps).
Once you have all the above concepts figured out, know how each device talks
on the network. Know which devices uses which addresses, MAC or IP. Know the
difference between Token Ring and Ethernet. Know the networking topologies (ring,
star, mesh, etc.). Know the switch functions (address learning, forward/filter
and loop avoidance) and methods (store-and-forward, cut-through, fragment free).
Commit to memory the five steps to data encapsulation:
1. User information is converted into data.
2. Data is converted into segments.
3. Segments are converted into packets or datagrams.
4. Packets or datagrams are converted into frames.
5. Frames are converted into bits for transmission.
Know what effect hubs, bridges, switches and routers have on a collision and/or
broadcast domain. Know how and when to segment a network and how to set up VLANS.
Know the difference between a gateway and a garden-variety router.
Tip #7: Know Where It Lives
The CCNA expects you to know the difference between a MAC address and an IP
addresses and vice versa. MAC addresses are written in hexadecimal and IP addresses
are written in binary or dotted-decimal. So they actually look different. Just
compare them:
MAC address: 44-1F-45-53-54-00
IP address: 216.239.57.104
Now that you're thinking about them, you should know the IP address classes,
subnet masks and other relevant information. Here's another chart to help with
that:
| Class |
First Decimal Value |
High Order bit Value |
Subnet Mask |
Max number of networks |
Max number of hosts |
| A |
0-127 |
0 |
255.0.0.0 |
126 |
16,777,214 |
| B |
128-191 |
10 |
255.255.0.0 |
16,382 |
5,534 |
| C |
192-223 |
110 |
255.255.255.0 |
2,097,150 |
254 |
Know the difference between the host and network portions of an IP address:
216.77.133.249
Network Host
One more thing to remember about IP addresses and classes: The CCNA still assumes
IPv4, so you won't see IPv6 or anything that goes with it, such as hexadecimal
expressed IP address.
Tip #8: Subnet in Your Head
Think about it this way: Do you really want to be sitting there, no calculator,
sweating it out while trying to subnet on whatever writing material they give
as your precious time ticks away? Far better to have that question figured out,
quickly, correctly answered and off the monitor so you can move on. The best
way to do this is to learn to subnet in your head or at least with nothing more
than a quickly scribbled chart.
And you might be thinking you'll never have to subnet on the job, that there
are subnet calculators and, in any case, most of what a CCNA does on his or
her first job is maintain established networks and that this really isn't a
necessary skill. Tough. Cisco expects you to know how to subnet the day you
take the CCNA exam, so you'd better learn how.
Luckily, there are plenty of online sources on subnetting. In fact, some of
the best study links available online have to do with subnetting. Two of the
best are:
Tip #9: ISDN Is Not Obsolete
ISDN is still state-of-the-art on the CCNA and in life. Some techs will tell
you ISDN stands for "It Still Does Nothing" instead of Integrated
Services Digital Network. Fact is there are plenty of networks out there that
continue to use ISDN. DSL is faster but businesses can be very slow to implement
innovations, especially these days when companies are making few new investments
in technology. ISDN also is still the best choice for circuit-switched connections.
So you'll see it in life and you'll see it on the CCNA exam. You'd better know
it.
That means know the ISDN line types (BRI and PRI) and their channel makeup.
Know terminal equipment types (TE1, TE2, NT1, NT2, etc.). Memorize the ISDN
reference points (R between TE2 and TA, S between TE1 and NT2, T between NT1
and NT2, U between NT1 and LT) and the ISDN protocols (E, I and Q). Here are
a few links to help you do that:
Tip #10: Remember Your Test Taking Skills
This tip really isn't CCNA or even Cisco specific but it is important. The steps
in this tip are simple and I'm sure you've heard them before.
- Review a few things, maybe play with your router or router simulator a bit,
but don't cram the night before. If you've given yourself enough time to study
and learn what you'll need to know, there's nothing new you're going to learn
in a last minute cram.
- Get a good night's sleep.
- Get to the testing center at least 15 minutes early so you'll have time
to complete the center's paperwork and compose yourself to face the beast
alone.
- Relax. Take your shoes off if you want. Think of something calm or something
that cheers you or pray. Whatever it takes, do not be tense.
- Use the erasable board or scrap paper you are given to write down anything
you might find helpful during the exam, for instance, the subnetting sequence,
port numbers, commands, anything you might forget later in the stress of actually
taking the CCNA.
- Read each question carefully. Cisco is notorious for questions written to
trip up people who read too fast. I recall one question in which the crucial
information was contained in the last two words, and I almost didn't realize
the question was asking something other than what I thought it would. It would
be terrible to not pass the CCNA not because you didn't learn a specific concept
but because you answered a question other than the one you really were asked.
This has happened to others. Don't let it happen to you.
- Don't underestimate the value of the process of elimination. Most of the
questions on the Cisco exam will be multiple choice. If you aren't sure of
the answer to a question, figure out which answers definitely are wrong and
"guess" from there.
Bonus Tip! Useful Links for Further Study
Just to round out my other tips, I offer you these links you may find useful:
Good luck.
Karen A. Kidd is an independent
contract technical writer based in Saint Petersburg, Fla. She provides technical
manuals, articles and other writing on various network concepts and IT business
practices for business and online publications, including CertCities. The Marshall
University graduate holds Cisco, CompTIA, Novell and Microsoft certifications.
You can contact Karen about "My Top 10 Study Tips for Cisco's 640-607 CCNA Exam" at rewrew@rewrew.com.
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