Which prefix does Router1 use for Host A traffic
Interpret the components of routing table
Determine how a router makes a forwarding decision by default
Answer
Correct answer: D — Router1 uses the longest matching prefix 10.10.13.208/29 for traffic to Host A at 10.10.13.214.
[sampleXML/xmlfile-3_1.png] Refer to the exhibit. Which prefix does Router1 use for traffic to Host A?
Community Insight
The test measures longest prefix match logic in a routing table; the trap is picking a prefix that exists in the table (like 10.10.13.0/25 or 10.10.13.128/28) but does not actually contain 10.10.13.214, or one that is too broad.
This CCNA 200-301 question shows Router1's routing table with several 10.10.13.0/2x prefixes and asks which one is used to reach Host A at 10.10.13.214. The page establishes that Router1 performs a longest-prefix match, and that 10.10.13.208/29 (option D) is the most specific entry covering the host's address.
Learners most often choose B, 10.10.13.0/25, because it is a large, obvious entry in the table — but that prefix only covers 10.10.13.0 through 10.10.13.127, so it never matches Host A's 10.10.13.214 address.
Community Discussion (41 comments)
rmorganq
👍 2
Selected: D
D has the longest match for that IP address: 10.10.13.208-215
Landesque
👍 1
Selected: D
10.10.13.214 belongs to 10.10.13.208/29 network is the
Stephad
👍 1
Selected: D
10.10.13.214 is included in 10.10.13.208/29
aljofer
👍 1
Selected: D
the correct answer is D
aljofer
👍 1
Selected: D
I choice D
BoboMbatheni
👍 1
Selected: D
network 10.10.13.208/29 has got 6 usable IPs hence the host 10.10.13.214 is part of that subnet.
Alisame
👍 1
Selected: A
The host is in the network 10.10.13.208/29 (Network: 10.10.13.208, usable 10.10.13.209 -10.10.13.2014, broadcast: 10.10.13.2015)
JSMM
👍 1
Selected: D
/29 means 3 hosts bits ](2^3)-2]=6 hosts.
SDU2025
👍 1
Selected: D
10.10.13.208/29
anoop4487
👍 4
Selected: D
Host A has the IP address 10.10.13.214. The routing table in the exhibit shows different prefixes. The goal is to find the most specific (longest prefix match) route that includes 10.10.13.214. The routing table includes the following relevant prefixes: 10.10.13.0/25 – Covers 10.10.13.0 to 10.10.13.127 (Host A 10.10.13.214 is NOT in this range). 10.10.13.128/28 – Covers 10.10.13.128 to 10.10.13.143 (Host A 10.10.13.214 is NOT in this range). 10.10.13.144/28 – Covers 10.10.13.144 to 10.10.13.159 (Host A 10.10.13.214 is NOT in this range). 10.10.13.208/29 – Covers 10.10.13.208 to 10.10.13.215 (Host A 10.10.13.214 IS in this range). The best route is always the most specific match (longest subnet mask). 10.10.13.208/29 (Subnet mask: 255.255.255.248) is the most specific route that includes 10.10.13.214. This means Router1 will forward traffic to 10.10.13.214 using the 10.10.13.208/29 prefix.
divine_love
👍 2
Selected: D
D. 10.10.13.208/29 Explanation: Router1 uses the most specific prefix that matches the IP address of Host A, which is 10.10.13.214. The most specific prefix listed in the routing table that includes this IP address is 10.10.13.208/29. This subnet includes addresses from 10.10.13.208 to 10.10.13.215, which encompasses the IP address of Host A.
smashwell
👍 2
A. 10.10.10.0/28: This entry represents a directly connected network but doesn't include the network where Host A (10.10.13.214) resides. B. 10.10.13.0/25: This entry represents a subnet that includes Host A's IP address. Router1 can reach this subnet via GigabitEthernet0/0, so it's a viable option. C. 10.10.13.144/28: This entry represents another subnet but doesn't include the IP address of Host A. D. 10.10.13.208/29: Similar to option C, this entry represents a subnet that doesn't include Host A's IP address. From the provided options, the most appropriate prefix that Router1 uses for traffic to Host A (10.10.13.214) is B. 10.10.13.0/25 since Host A's IP address falls within that subnet range, and there's a specific route entry for it in Router1's routing table. Therefore, the correct answer is option B.
otonielsantos
👍 1
Selected: D
D - Router ospf 10.10.13.208/29 208 - network 209-214 - host 215 - broadcat
fanagebregergs
👍 1
I couldn't access the rest of the questions if someone pls help me.?
Jacky2020
👍 1
10.10.13.208/29 and the entire IP acts as a Network ID, so the first IP is: 10.10.13.209, the last IP is: 10.10.13.214 and this last IP would be assigned to Host A, therefore, the router will go through 10.10.13.208/29 to reach to Host A. Hence, the answer must be D
AceRizzla
👍 2
if we consider /29 , and quickly subnet we got next result Network ID : 10.10.13.208 First host :10.10.13.209 Last host : 10.10.13.214 Broadcast :10.10.13.215 Next subnet 10.10.13.216 so the correct answer is "D"
EkaRulez
👍 2
Selected: D
D is the correct answer. The range of network 10.10.13.208/29 includes the ip address 10.10.13.214
Goosaar
👍 1
Selected: D
The correct answer will be D because the route gives correct range
duongccna
👍 1
select D, because 10.10.13.214 is a subnetwork of 10.10.13.208/29
S089765
👍 1
Selected: D
D fall in range
ziyod2005
👍 1
Selected: D
10.10.13.214 IPv4 address belongs to the 10.10.13.208/29 subnet and router will choose this one as the best route
Hope_12
👍 2
Selected: D
D.10.10.13.208/29 Host A = 10.10.13.214 10.10.13.208 has inc of 8 from /29 with highest subnet mask(Longest Prefix) 10.10.13.208 - 10.10.13.216 is in range for 10.10.13.214
Mgardini
👍 1
Selected: D
Answer is D Due to Longest Prefix path
Request7108
👍 2
D is the correct answer because it is the most specific path with a match for the host. Other folks have mentioned the "longest prefix" but I prefer calling it the "most specific" path
remoto
👍 1
Selected: D
D is correct
javachip
👍 1
Selected: D
router selects longest prefix path
NetworkRookie
👍 1
Selected: D
Router selects longest Prefix path from routing table.
keokkeo_123
👍 1
Selected: D
is correct
nyasalandi123
👍 1
D is correct as it is in the same network range
Chiefthings
👍 3
It’s a trick question but the obvious answer is D. In order to reach Host A, you need to be in its network.
aosroyal
👍 1
Selected: D
correct
Samir_123
👍 2
Selected: D
correct
mikachuu85
👍 24
10.10.13.208/29 gives .208 for network, hmin 209, hmax 214, bcast 215. The correct answer will be D as this route gives the correct range.
vira5489
👍 3
Selected: D
correct
aman87
👍 1
D is correct.
Adam128
👍 2
what is the signifcation of ".2" or ".1" ?
dave1992
👍 8
i belive it is a shortened way of saying 10.10.10.1 and 10.10.10.2 since you can see on the other side the subnet, i think you can assume the .1 or .2 goes at the end there.
ZUMY
👍 15
D is correct: *Router selects longest Prefix path from routing table.
ZUMY
👍 4
It’s a trick question but the obvious answer is D. In order to reach Host A, you need to be in its network.
NZIAKOU
👍 3
D is the correct answer.
Ali526
👍 4
D is correct.
Comments & Corrections
No comments yet — spotted an error or have a note? Share it below.
Expert Analysis
Why the Answer Is Correct
Host A sits at 10.10.13.214, and the 10.10.13.208/29 entry breaks down as network 10.10.13.208, usable range.209–.214, broadcast.215, so the host falls inside this subnet. When multiple entries match a destination, a router chooses the one with the longest prefix length, and /29 is the most specific mask among the candidates, so Router1 forwards via 10.10.13.208/29. As mikachuu85 calculated, ".208 for network, hmin 209, hmax 214, bcast 215" confirms the range covers the host.Why the Other Options Are Wrong
A, 10.10.10.0/28, belongs to a completely different third octet (10.10.10.x), so it can never match a 10.10.13.x destination. B, 10.10.13.0/25, spans only 10.10.13.0–10.10.13.127, which excludes.214. C, 10.10.13.144/28, covers 10.10.13.144–10.10.13.159, so it is also a non-matching entry; even if it matched, its /28 mask would lose to the /29 only if /29 weren't present, which is not the case here.Community Comment Notes
The community converges on D, with multiple commenters echoing that "D has the longest match for that IP address" (rmorganq) and anoop4487 systematically ruling out each non-covering range. ZUMY and Chiefthings frame it as a trick question whose real point is that traffic must match a prefix containing the host. One comment about "a shortened way of saying 10.10.10.1 and 10.10.10.2" is a distraction from the exhibit's actual matching logic and should be disregarded.Exam Strategy
For routing-table questions, first convert each candidate prefix to its network, first usable, and last usable address before comparing masks. Then apply the two-step rule: keep only entries that actually contain the destination, and among those pick the longest prefix length.
Frequently Asked Questions
Why doesn't Router1 use 10.10.13.0/25 for Host A at 10.10.13.214?
10.10.13.0/25 covers only 10.10.13.0 through 10.10.13.127, so Host A's address 10.10.13.214 falls outside it and this entry never matches.
How do you quickly check that 10.10.13.208/29 contains 10.10.13.214?
A /29 block is 8 addresses: network 10.10.13.208, usable .209–.214, broadcast .215. Since .214 is the last usable host, it belongs to this subnet.
Related Analysis
Practice All 200-301 Questions
Access 220 questions with complete answers and detailed explanations.
View Full 200-301 Practice Test →