all 7 comments

[–]delta301 1 point2 points  (6 children)

From my Scaling Networks Companion Guide v6:

  • 802.1d is the original STP standard and is also known as CST (Common Spanning Tree). One spanning-tree instance for the entire bridged network, no matter how many vlans you have

  • 802.1d is the same standard for PVST+, which is the Cisco enhancement of the original STP, and allows a seperate spanning-tree instance for each vlan

  • 802.1w is the standard defined for Rapid STP (RSTP), and its only difference from the original STP is faster convergence

  • Rapid PVST+ is Cisco's enhancement of RSTP, therefore it uses the 802.1w standard as well

  • MSTP has the standard 802.1s

I couldn't exactly remember off the top of my head. You should get that book, it saved my life and helped me pass my practical + exam :D

[–]look_ma_no_feet[S] 0 points1 point  (5 children)

Right on thank you.
So it would appear the PVST isn’t part of a standard then, as it only inter operates with an ISL infrastructure

[–]delta301 0 points1 point  (0 children)

I would imagine so, yeah

[–]tee_and_essCCNA 0 points1 point  (3 children)

note that there is pvst and pvst+. pvst is the one that will only work with ISL, whereas PVST+ will work with 802.1q

That was a point of confusion for me to.

[–]itslateCCIE 0 points1 point  (2 children)

I can't believe isl is still taught, it's nowhere in real world environments

[–]erh_PracticalNetworking.net 0 points1 point  (1 child)

Seriously. Even modern Cisco switches don't support it anymore. =)

[–]delta301 0 points1 point  (0 children)

this is what I've been thinking while going through some of the Cisco stuff. like, mention it sure but what's the point in anything more???