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58 lines
2.2 KiB
TeX
58 lines
2.2 KiB
TeX
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\section{Spanning Tree}
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Spanning Tree exists for the \textbf{sole} reason to save "your" network and all the broadcast storms an network engineer having a bad day can by mistake create!
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STP comes from the above desire where redundancy was wanted but no protocol existed before STP to help in this regard.
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\begin{table}[h]
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\centering
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\caption{Spanning Tree standrds}
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\label{stpstandards}
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\resizebox{\columnwidth}{!}{%
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\begin{tabular}{|l|l|l|l|l|}
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\hline
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\textbf{} & \textbf{Standard} & \textbf{Ressource Usage} & \multicolumn{2}{l|}{\textbf{Convergence}} \\ \hline
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CST & 802.1D & Low & Slow & All vlans \\ \hline
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PVST+ & Cisco & High & Slow & Per vlan \\ \hline
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RSTP & 802.1w & So-so (Med.) & Fast & All vlans \\ \hline
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RPVST+ & Cisco & On-the-double (V.High) & Fast & Per vlan \\ \hline
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MST & 802.1s & Med. - High & Fast & Vlan list \\ \hline
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\end{tabular}%
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}
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\end{table}
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\subsection{Port Roles}
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When a switch is enabled for Spanning Tree. One of the following roles will have been assumed by any port on the switch in question.
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\begin{itemize}
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\item \textbf{Root port:} Only 1 port on any switch (non-counting the root bridge!). Is always the port with the lowest metric (aka. best path) to the root bridge.
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\item \textbf{Designated port:} A designated port is the port on any segment closest to the root bridge and forwarding traffic.
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\item \textbf{\textit{Non}-designated port:} Put in blocking mode and not currently forwarding traffic.
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\item \textbf{Disabled port:} The port has been one-way-or-another shut down.
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\end{itemize}
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\subsection{Standards}
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\subsubsection{STP}
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\subsubsection{PVST}
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\subsubsection{RPVST+}
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\subsubsection{MST}
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\subsection{Features}
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\begin{itemize}
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\item PortFart
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\item UplinkFast
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\item BackboneFast
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\item BPDU Guard
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\item BPDU Filter
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\item Root Guard
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\item Loop Guard
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\item Unidirectional Link Detection (UDLD)
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\item FlexLinks
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\end{itemize}
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