Problem $5[20$ points$]$

Assume that a network administrator has been assigned the following IP space: $193\mathrm{.}91\mathrm{.}192\mathrm{.}0/23$ that can accommodate $512$ hosts. The network administrator wants to divide this space into three subnets, shown in the topology of Figure $1.$ Split the available IP space into three subnets. Subnet $1$ has $256$ hosts, and subnets $2$ and $3$ have $128$ hosts each. Determine,

$($a$)[5$ points$]$: The subnet number and subnet mask for each of the three subnets.

$($b$)[5$ points$]$: The ranges $($first and last IP address$)$ for each subnet.

$($c$)[5$ points$]$: Assign an IP address to each network interface connected to each subnet. Compose the forwarding table of R$1.$

$($d$)[5$ points$]$: Apply the subnet mask on the IP addresses that you assigned to H$1,$ H$2,$ and H$3$ to demonstrate how the application of the subnet mask maps the IP address to the corresponding subnet number.