$(1)(4$ pts$)$ A ring network shown below uses a distance vector routing protocol. Assume the

following in the discussion below:

i$)$ The link metric is hop count and that a direct connected broadcast domain has the hop count $=$

$0.$

ii$)$ Routers' IDs are A to $H$ as shown below. Each router has only one broadcast domain attached

to it and they are represented by the lower case letter of each router's ID $($e$.$g$.$ broadcast$-$domain

$a$ is attached to router $A,$ etc$).$

Each entry in a routing table contains the following information as shown below:

Destination broadcast domain

Metric

Next hop.

At $t=0,$ each router only contains its attached broadcast domain in its routing table. Routers

exchange routing tables at $t=10,20,30,$dots simultaneously. We can ignore the time required for

exchanging and processing the routing tables. $($a$)$ What is the routing table in node $B$ at $t=15,$

$($b$)$ at $t=25sec.$