STP root selection

[Superd04]

A question here from testking questions.. dont think they're explanation is very good.. can anyone explain to me (in layman terms) how this selection process works in relation to this question..
thanks in advance

http://img.villagephotos.com/p/2005-1/930106/question.jpg

 

[CiscoGuy33]

Superd04,

Question - What books are you using to study for CCNA or are you just using TestKing?

You are very right - TestKing does not have a very clear explaination - STP is very complex and very important for a CCNA to understand - I would suggest reading the section on STP from Wendell Odom in CCNA Official Exam Certification Library, 2nd Edition or Todd Lammle in CCNA: Cisco Certified Network Associate Study Guide, 5th Edition.

TestKings lead to "Paper CCNAs"

Just my thoughts!



E.A. Broda
CCNA, CCDA, CCAI, Network +

 

[techkiwi]

You could also try searching on Cisco.com, but I imagine you will have a fair amount of information to wade through. As CiscoGuy33 says, spanning-tree is complex, especially when you start to look into all the different variants.

Graham

 

[jtphoneman]

Cant read the question well but i'm sure you know the root is elected by its bridge priority, if it is the same as other switches then the mac makes the desicion(the lower i.d. wins the root election)For the other switches the port one with the lowest cost to the root will win, cost consists of speed (bandwidth) to the root. If the cost are the same once agian the lowest MAC I.D. wins the electioin. Making it a designated port. Hope this helps.

 

[Fartout]

The path cost is very important in stp protocol, to converge , stp make test to every distination based on the link between switches, and keep only the best path , the lowest cost

In this exemple if you have a packet send from Testking C to Testking A the best way is via switch Testking D, that's mean 1G+1G is better then 100 Mbps.

all port with 100Mbps will be blocked.

A+