The following parameters are defined for a switching network:

$$ Number of hops between two given end devices$=$ N

$$ Length of a message$=$M bits

$$ The data speed $=$ B bps $($bits per second$)$ on all network links

$$ Fixed packet size $=$ P bits

$$ Header size $=$ H bpp $($bits per packets$)$

$$ Call set up time $($for Circuit switching$)=$ S sec$.$

$$ Propagation delay per hop $=$ D sec$.$

$5$

For N$=4$ hops, L$=3200$ bits, S$=0\mathrm{.}2$sec$,$ B$=9600$bps$,$ P$=1024$bits, D$=0\mathrm{.}001$sec and H$=16$bpp$.$ Find the

end$-$to$-$end delay for circuit switching and datagram packet switching. Assume that no

acknowledgement and processing delay exist at the nodes. $(15$ points$)$

Hint: For CS: let end$-$to$-$end delay $=$ C$1+$ C$2,$ where

C$1=$ Call Setup Time

C$2=$ Message Delivery Time$=$Propagation Delay $+$ Transmission Time

$($Consider how to determine transmission time$).$

For Datagram Packet Switching: let end$-$to$-$end delay $=$D$1+$ D$2+$ D$3+$ D$4,$ where

D$1=$ Time to Transmit and Deliver all packets through first hop

D$2=$ Time to Deliver last packet across second hop

D$3=$Time to Deliver last packet across third hop

D$4=$Time to Deliver last packet across forth hop.