Exam 70-741 topic 1 question 16 discussion

Answer is A 172.16.0.0 /12 is the subnet ID of 172.16.10.50 That is the best route. Instead of the default route

Answer is A. 172.16.10.50 is directly connected

A. Server1 will attempt to connect directly to 172.20.10.50. >>Now correct answer B. Server1 will route the connection to 10.10.0.2. >>If you attempt to 10.20.200.1-254, it's correct. C. Server1 will silently drop the connection attempt. >>I don't know when it's correct. D. Server1 will route the connection to 192.168.2.1. >>If you attempt to 172.32.10.50, it's correct.

I tested it with adding routes like in the example: The correct answer is A! when you add a route for 172.16.0.0 Mask 255.240.0.0 on the client you want to ping from, the client ignores the default gateway and attempts to connect directly to 172.20.10.50 even tough the Metric was lower on the Default Gateway. Which means a route has a higher priority than the default gateway 172.16.0.0/12 contains the Adress of 172.20.10.50 which is why it takes this route

amazed how many people dont understand how subnetting works. 255.240.0.0 = subnet mask of 12 = total possible amount of IPs = 1,048,576. range = 172.16.0.1 - 172.31.255.254. this range covers the IP address in question. In a network route, it will always try to match the 'destination' as much as it can, before looking at Metrics. Metrics are used when there are more than 1 route available for the same thing. Answer is A

D is correct answer

So is A. correct because of lowest metric Default Gateway or D. because of on-link??

The correct answer is A) Server1 will attempt to connect directly to 172.20.10.50 Route Determination Process for WINDOWS: [ To determine which routing table entry is used for the forwarding decision, IP uses the following process: The list of matching routes is compiled. The route that has the longest match (the route that matched the most amount of bits with the destination IP address) is chosen. The longest matching route is the most specific route to the destination IP address. ] When the address 172.20.10.50 needs to be looked, the longest prefix of the candidate routes is 172.16.0.0/12, since its subnet mask (/12) is longer than the 0.0.0.0 entry's mask (/0), making the route more specific. Here We can view better: https://drive.google.com/drive/folders/1lhNkTgRRfN85HXVbvFljKzcdgM5OuhMU?usp=sharing URL: https://en.wikipedia.org/wiki/Longest_prefix_match https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-2000-server/cc958823(v=technet.10)

Even though the address 172.20.10.50 is part of network 172.16.0.0/12 which is in this range 172.16.0.1 - 172.31.255.254, answer D is correct because of the lower metric

The correct answer is A) Server1 will attempt to connect directly to 172.20.10.50 What is difference between administrative distance and metric? Administrative Distance: is used for a router to choose a route to reach the same subnet when more than one routing protocol is used to reach it. The route in the routing protocol that has the lowest administrative distance will be the best route . Metric: If a router learns two different routes for the same network with the "same routing protocol" , it must decide which route is better and will add it to the routing table . Origin of the route -> Administrative distance ON-LINK -> 0 The default route is used when the route is not matched by any other entry in the routing table. So the default route is programmed to use it as a "LAST RESORT" because any packet with unknown destination, it should be send to this interface/ip of default route. If there is no default-route then the packets will be dropped 172.16.0.0 is on-link ->0 then the default route is not used So in this case Server1 will attempt to connect directly to 172.20.10.50

Server1 will attempt to connect directly to 172.20.10.50. The routing table contains an entry for the destination 172.16.0.0 / 255.240.0.0. This network includes the address range 172.16.0.1 to 172.31.255.254. The interface used for the network is "On-link". This means that the network is reachable without using a router.

D, Is the answer. Eventhough 172.16.0.0/12 is directly connected, it happens that his route metric is greater than the default route metric. That's why A is not the answer.

Answer D is correct. There is not route for 172.20.x.x so basically it will to to the default route.

Because the CIDR is a /12, the subnets would be: 172.16.0.0 172.32.0.0 172.48.00 and so forth Which means that there is no route entry for the 172.20.0.0 subnet. So what does the computer do when it receives an IP address that it doesnt know what to do with.. it sends it to the default gateway.. 192.168.2.1

Looks like it should be 172.16.0.0/12 because it has the longest matching network address: (see "Route Determination Process") https://docs.microsoft.com/en-us/previous-versions/bb727001(v=technet.10)

This is clear as water. Nothing has to be routed because the host is directly connected. Answer is A

we guys are really thinking too much. in routing, the first thing a routers does is to check if the destination is local i.e directly connected and if not, it forwards it to the default gateway. In this case both A and D could be the answer but since the qsn says what will occur when server attempt to connect to the network, the first thing it will do is to first attempt to connect to it. if it is unsuccesful, then it will forward it to the default gateway only becuase there is a defualt route else it would have dropped the packet. so the answer is A