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CCNA Exam - Question 89


Which network action occurs within the data plane?

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Correct Answer: A

The data plane, also known as the forwarding plane, is responsible for moving packets from one interface to another. Actions that occur in the data plane include processing packets that pass through the device, such as forwarding packets based on destination IP addresses, de-encapsulating and re-encapsulating packets, and replying to incoming ICMP echo requests. ICMP echo request and reply messages are handled directly by the forwarding mechanism without requiring routing decisions or control plane involvement. Therefore, replying to an incoming ICMP echo request is an action that occurs within the data plane.

Discussion

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Dante_DanOption: D
Jan 29, 2022

Extracted from Book #2, page 359: "... the following list details some of the more common actions that a networking device does that fit into the data plane: - De-encapsulating and re-encapsulating a packet in a data-link frame (routers, layer 3 switches). - Adding or removing an 802.1Q trunking header (routers and switches). - Matching an ethernet frame's destination MAC address to the MAC address table (layer 2 switches). - Matching an IP packet's destination IP address to the IP routing table (routers, layer 3 switches). - Encrypting the data and adding a new IP header (for VPN processing). - Changing the source or destination IP address (for NAT) processing). - Discarding a message due to a filter (ACLs, port security). All the items in the list make up the data plane, because the data plane includes all actions done per message."

sgashashf
Feb 25, 2022

This blows my mind, considering I've read from multiple different sources that "the Control plane refers to all functions and processes that determine which path to use to send the packet or frame." I now have no idea how to differentiate between these two planes.

jose01210
May 17, 2022

igual me pasa a mi

c6006
Apr 4, 2024

the lookup is done at the data plane. the population of the routing table is done by the control plane

jose01210
May 17, 2022

igual me pasa a mi

c6006
Apr 4, 2024

the lookup is done at the data plane. the population of the routing table is done by the control plane

MDK94
Jun 29, 2022

ICMP = internet CONTROL message protocol "The role of ICMP is to provide information about the path the data is taking from its point of origin to its destination. It has the same basic structure as an IP packet, but despite that, it's not really goodput. It's there to control 'how things are done', therefore, is part of the control plane."

michael1001
Dec 11, 2022

Underrated

splashyOption: D
Jan 11, 2023

https://ipwithease.com/cisco-express-forwarding-cef/ I think it's a CEF question: FIB and adjacency tables are in data plane, once these are "established" the data won't pass through the cpu any more.

LordScorpiusOption: D
May 4, 2022

If you can subnet from /20 to /30 and you know the contrast between TCP and UDP, and you learn the data types for the three planes...you WILL pass the CCNA.

xbololi
Jun 30, 2023

DHCP, ipv6, DTP, VTP, ACL, Static Routing: Am i a joke to you? xD

ZUMY
Apr 27, 2022

Going with D Think of the control plane as being like the stoplights that operate at the intersections of a city. Meanwhile, the data plane (or the forwarding plane) is more like the cars that drive on the roads, stop at the intersections, and obey the stoplights.

Kane002Option: A
Jan 7, 2022

Actual management of data is data plane, hence responding to an ICMP message is within the data plane, whereas routing decisions are made by the control plane, hence A not D.

docoj99382
Jan 18, 2024

My answer is B. It is question about SDN. Centralized Controller forward instructions to Data Plane each device.

[Removed]Option: D
Mar 15, 2024

D is correct

riteshm42Option: A
Feb 7, 2025

Both A and D comes under data plane. D : Comparing a destination IP address to an IP routing table falls under the data plane in networking terminology; this is because the data plane is responsible for the actual forwarding of packets based on the information in the routing table, which includes looking up the destination IP address to determine the next hop A: While the control plane would be responsible for determining the routing path for the ICMP echo request, the actual sending and receiving of the echo request and reply happens on the data plane.

pagamar
Apr 14, 2022

Tumbative: I saw this question in a recent Exam, and the RIGHT answer is D, 100% correct in Topic 6 of the Exam.

iMo7edOption: D
Feb 6, 2023

It's D

Hangulmal
Aug 9, 2023

The data plane is accountable for the actual transmission of data packets across a network. It entails determining, based on a packet's destination address, the appropriate outgoing interface for it. This procedure typically involves looking up the destination IP address in the routing table to ascertain the next network hop for the packet. The comparison of the destination IP address with the IP routing table is a crucial data plane operation. Answer: D

onyia.edward
May 26, 2024

Think of the control plane as being like the stoplights that operate at the intersections of a city. Meanwhile, the data plane (or the forwarding plane) is more like the cars that drive on the roads, stop at the intersections, and obey the stoplights. I hope this help someone understand better

AndersonMrOption: D
Jan 16, 2022

icmp is control plane

daanderudOption: D
Jan 18, 2022

Agree. RESPONDING to ICMP is in the data pane

daanderud
Jan 18, 2022

I meant A!

reagan_donald
Jan 19, 2022

The role of ICMP is to provide information about the path the data is taking from its point of origin to its destination. It has the same basic structure as an IP packet, but despite that, it's not really goodput. It's there to control 'how things are done', therefore, is part of the control plane. Correct answer is D

NicociscoOption: A
Jan 29, 2022

C'est la A car la dataplane forward le trafic

debut01
Feb 12, 2022

je pense que c'est la B

KnobblerOption: A
Feb 27, 2022

I’m going with A :)

lxxxxxxxxx
Nov 12, 2023

control plane runs routing protocols, thus the answer is D

1stAidOption: A
Dec 31, 2023

Data plane layer2= ICMP... Layer3= control plane, IP, routing

KuyaErik101Option: D
Mar 26, 2024

Correct

MistyUnicornOption: A
Oct 31, 2024

A is correct

Omooba_Adeposi
Nov 6, 2024

The correct answer is: A. reply to an incoming ICMP echo request Explanation: The data plane (also known as the forwarding plane) is responsible for the actual movement of data packets across the network. Actions in the data plane include forwarding packets, filtering packets, and responding to certain protocol requests, such as ICMP echo requests (i.e., ping responses). Here’s a breakdown of why the other options are incorrect: B. Making a configuration change from an incoming NETCONF RPC is a control plane activity. The control plane handles management and control tasks like configuration changes.

Omooba_Adeposi
Nov 6, 2024

C. Running routing protocols (like OSPF, EIGRP, RIP, BGP) is a control plane function, as it involves creating and maintaining the routing table rather than forwarding individual packets. D. Comparing the destination IP address to the IP routing table is part of the control plane operation as well, where decisions are made on the best path to forward packets. However, the actual forwarding of packets based on that decision happens in the data plane. Thus, replying to an ICMP echo request is a direct network action that occurs in the data plane.