Sitting for the CCNA

[GT1999]

A small CCNA story from a college student:

Before the beginning of September of this year, I knew nothing about Cisco equipment. Sitting here now in the middle of December, I feel confident I understand a lot of basic fundamentals that the CCNA requires. I took a CCNA prep class as part of my BS degree from a State University all crammed into one semester. It included hands on labs every week for 2 hours, and class discussion two times a week. Subnetting was thrown at us the first day we sat down for lab, and it never was an easy class. The goal was to take the CCNA around final exams, and if we passed, the teacher would give us a 100% for our final exam grade (25% of our grade) -- otherwise, we had to take his exam -- which would be easier than the CCNA, but we wouldn't get that nice 100% no matter what our grade was on the CCNA.

The end of the semester rolls around, and only one guy in the entire class of ~30 passed the CCNA, while about 10 tried. The rest of the class was scared to take it, including me. So of course, I took the final exam, and got a B on it. Our teacher is now letting us take the exam over winter break (before Jan 18th), and if we pass it, he'll put a change of grade form in. Additionally my dad says he'll shell out the $125 for the exam, but only the first time. So I guess I have nothing to lose.

Strengths:
Static & Dynamic routing as the CCNA would expect
Subnetting A,B,C as the CCNA would expect (inside and out -- trust me!)
Basic OSI
6 years of self taught and work-taught (ISP) knowledge

Weaknesses:
WAN (specifically Frame Relay and its acronyms, but more importantly, its implementation)
VLANs -- I know nothing about these -- our teacher practically never went over them
DDR for ISDN
Advanced OSPF with ABRs and the like, and how to determine what networks are in area 0/1/2 etc ...


Cliff notes: Given the strengths and weaknesses above, do you think I can pass the exam in less than a month?

I'm planning on taking the exam again if I do not pass, and I have the v51 testking questions (though I refuse to pay for them, I got a copy free), which I'm studying over as well. I also have the 4th edition Sybex book -- my textbook from class.

Starting Jan 18th I start a temp job working as an NT/XP Sys Admin -- unfortunately that doesn't include much if any Cisco experience. Then I go back for Fall 2005 semester and graduate with a BS in Telecom Mgmt.

 

[ScottMac]

On your list of "Weaknesses:" VLANs - you're gonna have to work on that. VLANs are (usually) on the test.

ACLs are also covered pretty well. You gotta know ACLs.

There's a fair amount of subnetting on the test ... in the form of: Given the address: aa.bb.cc.dd /18, which of the following belong to the same subnet? Choose all that apply. <then a list of ~8 addresses> then you choose the four/five/six addresses.

I've seen questions with two network segmants connected by an unidentified box. There's an address above each segment and the question is "What kind of device does the box have to be in order to pass traffic" (hub, bridge, router (and a couple of ringers). (OSI model and subnetting in one question).

There are usually a couple SIMs, some troubleshooting, some configuration, some ACL work.

At CCNA level, you're pretty much limited to single area OSPF questions, but I believe you still need to know the basics of OSPF overall (all areas must connect to area zero, ABR, ASBR, Virtual Link, Stubby, Not-So-Stubby, totally stubby, adjacencies, what an LSA is and does ...)

You'll probably have at least two or three questions on the ISDN reference points (Q, R, S, T, U, DTE, DCE, NT(1|2), signaling, bearer channels versus "D" (delta) channels, etc).

I don't know what you know relative to the test, and neither do you (at this point). My suggestion would be to download the Boson 801 CCNA test (#3 has 900+ questions and SIMs - ~US$79.00) study your books and take the challenge tests until you can consistantly hit mid-ninties .... then hit the real thing. It's the cheapest way, trust me.

DO NOT start slumming the braindump sites. Upwards of 25-30% of the Q&amp;A on those sites are dead wrong ... and it's very hard to "unlearn" things (right or wrong). TestKing is also loaded with bad Q&amp;A. It's popular (anything free or cheap is), but there's a lot of bad info up there (not meaning to pick on TestKing ... they all suck pretty bad).

Don't memorize it. LEARN it, understand it, then take the tests.

Good Luck

Scott

 

[GT1999]

Awesome, thanks for the advice.

I know what you mean about CIDR (I think that's what you're getting at with subnetting), and that shouldn't be a problem for me.

32-bits for an IP address, and it's all very visual. This is how I was taught:

255.0.0.0 = /8 (8 bits on)
255.255.0.0 = /16 (16 bits on)
255.255.255.0 = /24 (24 bits on)
255.255.255.255 = /32 (All 32 bits on)

subnet table (memorized):
1
128 - up to 127 is A = +1 bit for CIDR
192 - up to 191 is B = +2 bits for CIDR
224 - up to 223 is C = +3 bits for CIDR
240 - up to 239 is D = +4 bits for CIDR (multicasting)
248 - up to 247 is E = +5 bits for CIDR, etc. (experimental)
252
254
255

Subnets: ((2^X)-2) where X is on bits (1's)
Hosts: ((2^X)-2) where X is off bits (0's)

Subnets: 256-mask = network addr. add to itself until you reach the mask = subnet network addresses.

For ISDN, I make 4 boxes: [TE1/2]--(R)--[TA]--(S)--[NT2]--(T)--[NT1]--(U)--*ISDN*

I don't think I want to shell out $79, but I'm going to focus on those weak points in my textbook. I'll definitely consider purchasing those, though -- since you think it's the cheapest route. All this stuff is so expensive... for an exam that expires in 3 years. I love this stuff and I really want the cert though -- ugh.

P.S. You forgot I &amp; E for ISDN.

 

[ScottMac]

Try this:

..1 | 1 | 2 | 2 | 2 | 2 | 2 | 2
..2 | 9 | 2 | 4 | 4 | 5 | 5 | 5
..8 | 2 | 4 | 0 | 8 | 2 | 4 | 5

128 |64 |32 |16 |8 | 4 | 2 |1

(the bit count above or below the mask value for the bit position - the forum doesn't hold spaces)

Draw the above on paper.

If you get a traditional mask (255.255.248.0, for example) draw a line to the left of the number. for a .248. the number below is "8" which will be the increment value ("magic number") for all of the networks / subnetworks (networks: 0, 8, 16, 24, 32, ...). If the two subnet numbers fall into the same range, they are in the same subnet).

If you get a CIDR - style mask, then count over the bits to add (8 + x, 16 + x, 24 + x) and draw a line to the right (same as the above example /21 - 16 +5 - five bits - line between 248 and 252).

The line also equates the CIDR bits to the traditional mask ... they will mix modes on the same list of addresses.

ALWAYS draw up a grid before you start the test (hit the "Start" button). It's easy to get "vapor locked" once the test starts. If you do a grid first, you can save seconds - to - minutes per question .... usually a "Good Thing" in case the SIMs get a little sticky.

Also remember the broadcast address is ALL ONES in the HOST portion of the address. There will be addresses with ".255." in one or more of the octets, and it WON"T be a broadcast address. There will also be some broadcast addresses that don't look like broadcast addresses (like 10.1.1.39 (/30 but you'll have to derive the mask from the other side of the connection)).

Study hard.

Good Luck

Scott