|
Home > Archive > CCNP > November 2003 > Error In CCNP self-study BCMSN book (642-811)
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
Error In CCNP self-study BCMSN book (642-811)
|
|
| DSComputers 2003-11-17, 11:52 pm |
| I found an error in the CCNP Self-Study CCNP BCMSN Exam Certification Guide for 642-811 from ciscopress.
The book contradicts itself in chapter 1.
Page 18 says quote:
This concept of network traffic patterns is known as the 80/20 rule. In a properly designed campus network, 80 percent of the traffic on a given network segment is local (switched). No more than 20 percent of the traffic is expected to move across the network backbone (routed).
Q&A of same chapter, page 30.
Question 3 is:quote:
In the 20/80 rule of networking, 20 percent of the traffic on a segment usually stays _____ while 80 percent travels _________.
Answers in the back of the book say blank one is local and blank 2 is travels across the network...which is obviously backwards 
*shrugs* just FYI for anybody reading this book. Not a huge goof I guess, forgivable. | |
|
| that question/answer is correct, there are different design.
The Multilayer Model
The New 80/20 Rule
The conventional wisdom of the 80/20 rule underlies the traditional design models discussed in the preceding section. With the campus-wide VLAN model, the logical workgroup is dispersed across the campus, but still organized such that 80 percent of traffic is contained within the VLAN. The remaining 20 percent of traffic leaves the network or subnet through a router.
The traditional 80/20 traffic model arose because each department or workgroup had a local server on the LAN. The local server was used as file server, logon server, and application server for the workgroup. The 80/20 traffic pattern has been changing rapidly with the rise of corporate intranets and applications that rely on distributed IP services. Many new and existing applications are moving to distributed World Wide Web (WWW)-based data storage and retrieval. The traffic pattern is moving toward what is now referred to as the 20/80 model. In the 20/80 model, only 20 percent of traffic is local to the workgroup LAN and 80 percent of the traffic leaves
http://www.cisco.com/warp/public/cc...es/highd_wp.pdf
link now work, points to pdf. section to look at:
"the multilayer model"
"new 80/20 rule" | |
| Johnno 2003-11-18, 4:09 am |
| Mikop,
I commend you on the research you conducted into this and the link you provided us to official documentation.
DSComputers point though, I believe, was that the reference taught one thing and tested on another. Now I am not 100% sure if that is the case as I have not been privy to reading the guide in question. However I am assuming that DSComputers would have noticed if anything else had been taught.
DSComputers,
What you could do, is send a letter to the author(s) asking them to clarify their teaching. Who knows, you may even get another reference from appreciative authors. A work colleague of mine wrote in with correction to another reference he was studying and the author rang him and thanked him for his input. He then sent him a signed copy of the latest edition of that reference.
Stay Safe.  | |
| DSComputers 2003-11-18, 9:36 am |
| Thanks for the replies guys. This was actually MY goof, not theirs. They do mention the 20/80 rule. Infact, parts of it are word for word the same as the linked article...though that white paper goes into much more detail on some things, good read.
Guess, I jumped to conclusions a bit 
Should stay away from studying so late at night, hehe. |
|
|
|
|