Friday, January 24, 2014

The Road to CCNP 642-902

Having completed my CCNA and all my classes (and then some) at WGU I decided to jump in on my CCNP studies. For those of you that don't know, the CCNP consists of three exams: CCNP ROUTE, CCNP SWITCH, and CCNP TSHOOT. It's common practice to start with ROUTE/SWITCH and the do TSHOOT last.

I decided to start with ROUTE. Why? Because a friend of mine posted a pretty great OSPF topology he was running in GNS3 and I wanted to try my hand at it. Here is my study plan so far:

  • CBT Nuggets Videos for CCNP ROUTE
  • Cisco Press CCNP ROUTE Book, by Wendell Odom
  • GNS3 Labs
  • Online Research

That sums up my current plans for Cisco Certifications. I have around 40 days left in my college semester and after that things will be hectic for a while as I try to get another 20+ credits out of the way.

TCP Flag Basics

TCP Flags are used for a variety of reasons. The 3-way handshake is likely the most common and well known (SYN/ACK), however all flags have their place and can greatly improve the flow of data and operation of applications. There are 6 different TCP Flags: Urgent, ACK, PUSH, Reset, SYN, and FIN As there are 6 flags, the TCP Flag field is 6 bits long. Each Flag has a bit that is either "on" [1] or "off" [0]. This is how the flag type is identified. I will now briefly touch on each flag and its uses.

The Urgent Pointer is the flag used to expedite the processing of a segment. When a receiving host receives a segment with the Urgent Pointer indicated, it sends it right to the front of the queue. I like to think of the Urgent Pointer as the "VIP" of the flags. When trying to gain entrance everyone has to wait their turn. However, when the "VIP" shows up, they are quickly brought to the front of the line and allowed in.

The Synchronisation (SYN) flag... definitely the first I learned about. SYN is used to establish connections as part of the 3-way handshake. To review, that involves Host A sending a SYN, Host B sending a SYN ACK, and Host A sending an ACK back to establish the connection.

Acknowledgement (ACK) Flags are used to indicate the successful receipt of a packet. With TCP, just about any data that is sent will receive an ACK back.

The PUSH flag is used to give data precedence over other packets, similar to the Urgent pointer. This is especially useful for applications whose integrity is compromised by too much delay (VoIP, video/music streaming, etc).

The RST (reset) flag is used when a segment arrives that isn't meant for the current session. When a host receives such a segment it sends out a RST and rejects the connection. This lets the sending device know where the mistake was made and initiate the correct connection.

The FIN flag (for Finished) is pretty much the opposite of SYN. When tearing down a connection Host A sends a FIN ACK, host B then ACKs, followed by a FIN ACK, which host A ACKs in response to. This completes the teardown.
I find it notable that data may continue flowing until both sides have shut the connection down.

Friday, November 30, 2012

Test Scheduled

Scheduled ICND1 for 12/10. I've created a study schedule that I've been following. My review of all the ICND1 topics will be completed Mid next week. At which point I get a nice relaxing Thursday followed by a long/intensive weekend. I'll be reviewing topics and doing practice tests friday night and saturday morning. Saturday afternoon will be labbing, subnetting, and troubleshooting. Sunday will be a general overview of any topics that I'm still not sure about.
I had originally scheduled the test for 12/3 but after writing out a study plan decided things would work far better with the extra week to prepare.
After I pass the test I'll dive right in to ICND2 content. I studied through Todd Lammles full CCNA book and already have a good grasp of the content. If everything goes to plan I'll be a full-blown CCNA by mid January.

From there I have some decisions to make. I'm very interested in the Security aspect of Networking so I may pursue my CCNA Security next. I know my first CCNP step will be R&S as I believe it is a good basis to have.

Keep an eye out for updates after I take the test. I'll put my impressions, challenges, and any other thoughts then!

Friday, November 2, 2012


I found a great site for a one-time CCNA practice test today. I say one-time because it does not dynamically generate new questions, content, or pull from a pool of questions. I scored a "Barely Pass" which ended up being an 80% (roughly). I was very pleased with this as I'm going the ICND1 + 2 route, and this was a composite test.
Most of my missed questions seemed to be on some protocol (OSPF) or topics I haven't gone in to yet (ACLs, Frame-Relay). I had done a decent amount of studying on OSPF a couple weeks ago and thought I had a decent grip on it. Apparently I need some clarification as I missed a good 4-5 questions on OSPF alone.
That being said, I'm fairly confident ICND1 is just about within striking range. It's time to nail down my commands, re-read my "CCNA Fast Pass" book by Todd Lammle, and schedule my study cram weekend and test date.

My one concern is that Halo 4 comes out on Tuesday. That's just 3 short days away. I'm going to buckle down this weekend and try to get some serious studying hours in to make up for the time I will likely miss playing Halo 4 on it's launch week and weekend. If I was living on my own this would be a HUGE distraction. Thankfully my wife is spectacular at keeping me on task and away from excessive 'binge-gaming' so I just might be able to schedule a test for mid November.

Wednesday, October 31, 2012

ICND1 Closing in!

Time for an update!

Preface: The content of this post is about my career networking studies. I am working my way up the cisco certification ladder. Beginning with the Cisco Certified Networking Associate (CCNA) - a 2 part test consisting of ICND1 and ICND2.

I've gone through all the content for ICND1 thoroughly and am reviewing and starting on ICND2 content now. My review consists of me going through various practice quiz's for different content that will be on ICND1. Right now I score between 70 and 100% on them all. I won't be taking the test until I can get 90% all the time. Just a goal I set for myself.

A big step in my learning (different from studying for exams) is that I now subscribe to a massive host of blogs. My RSS feed in Outlook has 3-5 new entries that I read through in the mornings. Learning a lot of interesting things about networking. A lot of it is obscure or something I may never deal with, but it is interesting to me.

At this point I've made an agreement with my wife. She says I have to get my certification before our 2nd baby comes. Technically that is supposed to be February of next year, but our last one came early. I'm going to finish my study progressions and once I am through all of the content one more time I'm going to schedule my exam and do an all weekend study binge before testing on a Monday. I have always had a good memory and have put a lot of effort in to improving it so the amount of hands on practice, reading, and reviewing I've done up to now - combined with a weekend of 12 hour study sessions should put me where I need to be.

My next update should be the week before that study session and testing.

PS: I'm using Forza 4 as my 'escape' right now. I enjoy racing games and I can think about difficult problems or take short breaks thanks to being offline and able to pause.