1. 2 key STP Concepts
2. 4 Step STP Decision Sequence
3. 3 steps of initial STP Convergence
4. 5 STP states
5. 3 STP Timers
6. Master the sh STP command
7. 2 types of BPDUs
8. Topology Change Process
9. Using STP in the real world
10. Determining root bridge placement
11. All of this per VLAN


Before I go way deep into the rabbit hole, I need to weed, for the CCNA, what do I need to commit to memory out of the 11? Here is the site, it is good, but deep?

http://www.knowcisco.com/content/15.../pt02ch06.shtml

I know 5 states (initially I thought there were 4) Forwarding, Listing, Learning, Blocking, but there is the administratively down) *Disabled* being the 5th state, and #10 determining the root bridge placement, lowest cost.
Any concise sites to STPs (directed at the basics)
This is what I would concider to be the scope on the exam on STPs
STP purpose - used in transparent bridging to ensure loop free path & provide redundancy
Blocking- default state-noframes forwared
Listening - Follows the blocking state. The switch is not forwarding frames but act in the STP process to determine whether to continue in the forwarding state.
Learning - Follows the listing state, still not forwaeding frames, prepareing to move to the forwarding state. The port
is looking at frames to learn the connected MAC addresses.
Forwarding - Frames which had not been so resently allowed to be forwarded, are now being forwarded,you finally are in normal operation.
Disabled - Follows the forwarding state. The switch,that was most resently, peacefuly forwarding frames,is now, not!

Cisco provides a way to bypass this state with "portfast" option, when a device connects to the switch and directly places the port into forwarding state

How deep is the rabbit hole

Sea*******out*******

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All I can say is: know STP well. If you learn the details on the site you just mentioned, you should have no probs.

Cheers,

Deets

P.S. I'm rather puzzled by your post...

*Deets scratches his head...

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Deets, I just want to be sure to study the reqiured material on stp.

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Deets, do you feel Lammle goes into enough detail re: stp?
thx

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While I can't comment on the version 2 exam because I never took it I will say the following:
You can't over study STP, especially if you are continuing on to the BCMSN's exam, but even more importantly you need to understand it in real life.

Do yourself a big favor and learn it well!

Yankee

Cisco LAN Switching (from Cisco Press) covers it in great detail.

[This message has been edited by Yankee (edited 01-08-2001).]

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Thanks Yankee
One more question
Where is the stoping pount for stp (ccna) for now, I must go over the rest of the requirements for the CCNA
Thanks in advance

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Hi Sea Dragon,

Sorry about my brief post before.

The best way, in my opinion, to learn STP is to understand EXACTLY what happens when your network topology changes, where BPDU's are being learnt, received and passed, what each of the states a bridge/switch is in while this is occurring, what the final outcome of the setup is - the states of the individual switches and where traffic is flowing. In short, you have to know the principles. My advice is to see if you can get examples of network topology changes, and what happens to a spanning tree and the bridge/switch states before, during and after the changes. For this topic there really isn't a predefined set of things you have to learn...you actually have to understand the topic as thoroughly as possible. I'll see if I can scrape up some sources that explain STP and what happens as a result of a network change.

To General Maximus: I would probably say that Lammle doesn't cover STP well enough. I think you need more sources - CiscoPress, plus the Cisco web site and Internet resources in general.

Cheers,

Deets

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Okay Thanks
To General Maximus: I would probably say that Lammle doesn't cover
STP well enough. I think you need more sources - CiscoPress, plus the
Cisco web site and Internet resources in general. the top of my head

BPDUs are sent in all states including Blocking and except for disabled right?

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quote:

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Originally posted by Sea Dragon:
BPDUs are sent in all states including Blocking and except for disabled right?

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Thanks Terje

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