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Next: RSVP/Backup Tunnels Up: Background Previous: Current Schemes

Preliminary Definitions

Please refer to Table 1 for a description of the terminology. Before we delve into estimating the delay for each scheme, we shall define the delay for a path. If $d_{DCN}(x)$ and $d_{OTN}(x)$ is the delay incurred due to a message travelling $x$ hops through the DCN and the OTN respectively, then:
\begin{displaymath}
d_{DCN}(x) = x\cdot (t_{proc} + t_{prop}) + t_{proc}
\end{displaymath} (1)


\begin{displaymath}
d_{OTN}(x) = \frac{b_{len}}{c}\cdot x
\end{displaymath} (2)

We shall follow the discussion in [7] and calculate the restoration delay as contributed by each phase of restoration. Hence:
\begin{displaymath}
t_{restore} = t_{detect} + t_{FIS} + t_{setup} + t_{switch}
\end{displaymath} (3)


Figure 1: The RSVP/Backup Tunnel serial restoration scheme.
\begin{figure}\begin{center}
\center \mbox{\psfig{figure=fig/Serial.eps,width=3.25in}}
\end{center}\end{figure}



Swapnil Bhatia 2002-08-02