Classic Spanning Tree and other different flavours

urviurvi Member Posts: 79 ■■□□□□□□□□
Hi I know of the Classic Spanning-Tree Protocol has a Listening State unlike RSTP and which has Max Age of 10 times Hello=20 secs and a Forward Delay of 15 secs . Then there is RSTP(Rapid STP Protocol) which has a Discarding State instead of a Blocking State like the Classic STP and also has no Listening State but only a Learning State ,further the RSTP has a Max Age of 3 times Hello =6 secs (default) plus no forward delay times in both Listening and Learning States.
So I can say that STP has 2 main flavors - Classic STP and RSTP? (correct me please if I am wrong).


Now my question is,what is PVST,PVST+ and Rapid PVST+?
Can I say that PVST= Classic STP that I stated above? Also, then to which flavor of STP does PVST+ belongs to - is it CLassic STP or Rapid Spanning-Tree?

If anyone can tell me which will be correct protocol flavor in the right side of the below table to which the left side belongs-
Abbreviation Flavor of STP
1)PVST = Classic STP/Rapid Spanning-Tree Protocol ?
2)PVST+ = Classic STP/Rapid Spanning-Tree Protocol ?
3)Rapid PVST+ = Classic STP/Rapid Spanning-Tree Protocol?
4)MSTP(Multiple Spanning-Tree Protocol) = Classic STP/Rapid Spanning-Tree Protocol?

Will be thankful if someone please clarifies. With Regards

Comments

  • urviurvi Member Posts: 79 ■■□□□□□□□□
    hello someone plz reply
  • GngoghGngogh Member Posts: 165 ■■■□□□□□□□
    Hi,

    If i remember PVST and Rapid PVST are Cisco proprietary protocols, and the main difference from standard STP and RSTP is that they can be customized per Vlan.
  • awitt11awitt11 Member Posts: 50 ■□□□□□□□□□
    PVST = Per VLAN Spanning Tree ; You are correct in stating that there is "classic" STP with slow timers and Rapid STP with faster timers. The other versions of STP deal with VLANS and how STP operates over a trunk, with each VLAN or group running separate instances of STP. PVST = ISL trunking (classic), PVST+ = 802.1Q trunking (classic), Rapid PVST+ = 802.1Q trunking (rapid)
  • Dieg0MDieg0M Member Posts: 861
    As far as Cisco is concerned, there is 3 flavours: PVSTP+ (default for IOS), Rapid PVSTP+ (default for NX-OS) and MSTP. You cannot run classic STP in Cisco, however you can reproduce STP by making a single instance in MSTP (but this is still MSTP and not STP). As for the difference between PVSTP and PVSTP+, there are several small differences but the one you should remember is that PVSTP+ is compatible with other vendors and that 802.1Q does not support PVSTP.
    Follow my CCDE journey at www.routingnull0.com
  • p1xelsp1xels Member Posts: 114 ■■□□□□□□□□
    Hi awitt and Diego But I never knew that STP dont support 802.1 Q trunking,also the term classic is just invented by me . I nowhere read in Wendell Odom's OCG that there is a classic STP. What I meant by classic STP is just STP. I meant there are - STP and RSTP. Now I dont think STP only supports ISL as that is nowhere written in the CCNA OCG .
  • tomtom1tomtom1 Member Posts: 375
    STP -> 802.1d
    RSTP -> 802.1w

    That would be the correct terminology to refer to STP. But, @Dieg0M, question about MST and using 1 instance to reproduce STP. I thought MST and RSTP work hand in hand so that even with a single instance / region, the characteristics would still be those of RSTP.
  • Dieg0MDieg0M Member Posts: 861
    Sorry for the confusion tomtom. You are indeed correct that MSTP uses the same convergence algorithm as RSTP. What I was trying to state is that you cannot have a single STP (or RSTP) in Cisco, unless you create a single MSTP instance.
    Follow my CCDE journey at www.routingnull0.com
  • HeeroHeero Member Posts: 486
    STP and RSTP are the two base modes of operation when it comes to spanning-tree. Then there are other modes built off of those modes. PVST is just STP, but it runs a separate STP instance per vlan. PVRST runs one RSTP instance per vlan. MST runs X number of RSTP instances and you map vlans to specific instances (middle ground between standard RSTP, and PVRST with one instances for EVERY vlan).

    Basically, the underlying mode of operation for all those different spanning-tree modes is either going to be STP, or RSTP.
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