IP Routing Questions
Question 1
Question 2
Explanation
The source and destination IP addresses of the packets are unchanged on all the way. Only source and destination MAC addresses are changed.
Question 3
Question 4
Explanation
Both the line “O 172.16.0.128/25” and “S 172.16.0.0/24” cover the host 172.16.0.202 but with the “longest (prefix) match” rule the router will choose the first route.
Note: Network 172.16.0.192/29 does not cover host 172.16.0.202. For network 172.16.0.192/29:
Increment: 8
Network address: 172.16.0.192
Broadcast address: 172.16.0.199
Question 5
Explanation
The default AD of static route is 1 so we need to configure another number for the static route.
Question 6
Explanation
From the output, we see R1 will use the entry “O 10.10.13.0/25 [110/4576] via 10.10.10.1, …” to reach host 10.10.13.10. This is a network route.
Note: “B* 0.0.0.0/0 …” is a default route.
Question 7
Explanation
Our new static default route has the Administrative Distance (AD) of 120, which is bigger than the AD of OSPF External route (O*E2) so it will not be pushed into the routing table until the current OSPF External route is removed.
For your information, if you don’t type the AD of 120 (using the command “ip route 0.0.0.0 0.0.0.0 10.13.0.1”) then the new static default route would replace the OSPF default route as the default AD of static route is 1. You will see such line in the routing table:
S* 0.0.0.0/0 [1/0] via 10.13.0.1
Question 8
Question 9
Question 10
Explanation
The destination IP addresses match all four entries in the routing table but the 192.168.16.0/27 has the longest prefix so it will be chosen. This is called the “longest prefix match” rule.
Question 11
Explanation
The prefix with “longest prefix” will be matched first, in this case is “/29”.
Question 12
Explanation
The Administrative distance (AD) of EIGRP is 90 while the AD of OSPF is 110 so EIGRP route will be chosen to install into the routing table.
Question 13
Explanation
Note: The “O 192.168.10.0/28” route ranges from 192.168.10.0 to 192.168.10.15 only so it does not include destination 192.168.10.16 so OSPF route is not the correct answer.
Question 14
Hi! Anyone can teach me. why is that everytime I click the question it appears the explanation only not the question?
@9tut where does those answers are coming from on question 10?
B. 102.168.16.0/24
C. 102.168 26.0/26
D. 102.168.16.0/27
@marie: They should be 192, not 102. Thanks for your detection, we have just fixed them!
@9tut – are You sure?
Both the line “O 172.16.0.128/25” and “S 172.16.0.0/24” cover the host 172.16.0.202 but with the “longest (prefix) match” rule the router will choose the first route.
I belive that administrative distance for static routes is 1 so Static will be taken as a first…?
I would be true with useing only ospf or static routes…?
Am I right?
@indeed: In this case the static route will not be chosen as the “O 172.16.0.128/25” route is more specific than the static route (longest prefix wins).
There is a variation to Question 6 asking to route to the Internet.
@9tut
Question 4: Can someone please help me if the longest prefix rule wins. Then why dosen’t / 29 (D) become the preferred choice.
@jonathan: Network 172.16.0.192/29 does not cover host 172.16.0.202. For network 172.16.0.192/29:
Increment: 8
Network address: 172.16.0.192
Broadcast address: 172.16.0.200
Hi 9tut,
I think there’s a little typo in the last part of the explanation of question 4 (regarding why network 172.16.0.192/29 is not the right answer) – the broadcast address should be 172.16.0.199 instead of 172.16.0.200 .
@Ahmed: Thanks for your detection, we have just fixed Q.4.
9tut is there any alternative payment except paypal ?
Has anyone taken an exam lately using 9tut?
@9tut and All.
I think there is a bit of typo in Q. 6 which asks “Which type of route does R1 use to reach host 10.10.13.10/32?”
I think the notation should read /25. i.e. “Which type of route does R1 use to reach host 10.10.13.10/25?”. There is no /32 on the diagram neither in the output.
OR If I am wrong, please explain. thanks.
@Moussa: The notation of IP-Address/32 (10.10.13.10/32 in Q#6) is common to refere to a specific host-machine. This is due to the fact, that the binary form of the IP-Address and the Subnetmask do get interconnected with a logical AND-function on routers, in order to determine the actual network address. As in a /32 Subnemask every bit is set to one this operation does return one exact IP-Address instead of a network, which in turn only belongs to the specified host.
Hi guys. When they say EIGRP, how do i know if they are talking about internal (90) or external(170) EIGRP? My question is based on Q12.
@9tut , The question 13 on the official exam says “O 192.168.10.0/28” , not “O 192.168.10.0/23)
@Lihle: If they only said “EIGRP” then we should think about internal EIGRP.
@Ed: Thanks for your information, we have just updated Q.13.
HI, Why in the Q6 the answer is Network Rout ? And why not a Default Roue ?
Thanks
Q4: A router evaluates routes in the following order.
Prefix Length – The longest-matching route is preferred first. Prefix length trumps all other route attributes.
Administrative Distance – In the event there are multiple routes to a destination with the same prefix length, the route learned by the protocol with the lowest administrative distance is preferred.
Metric – In the event there are multiple routes learned by the same protocol with same prefix length, the route with the lowest metric is preferred. (If two or more of these routes have equal metrics, load balancing across them may occur.)
Ivan because the default route is pointing to 10.10.10.18 internet’s interface not to PC 10.10.13.10
HI! Can someone explain Q14 plz
thx
Just wondering has anyone taken this exam after may 2022 and passed? Are these the actual questions
can someone tell me why regarding Q14 is that standard ??
S* 0.0.0.0/0 [1/0] via 10.10.11.2 <——- This is a static route and Admininstative Distance is 1. So this will over take other routes
hai this is here abdul i have neet ccnp notes any have please share .
Q14 – Can anyone please explain the question 14, why 0.0.0.0 / 0 is the answer
I cant even see some of the quesions ,
I went to examgo to view the rest of the questions for the exam.
I guess it for paying users ?
@Brijesh is 0.0.0.0 beacuse 10.10.11.2 is your way to arrive to internet is your net hop
I think that in Question 10 answer C has a type error. It should be C. 192.168.16.0/26 (not C. 192.168 26.0/26)
@George: Thank you for your detection, we updated Q10!