MPPSC 2021 Prelims Q28: To transfer data packets between two computer networks, a

Q: What is the answer to MPPSC 2021 Prelims Q28?

B or D (both accepted by the official key). Correct — B (Router) or D (Gateway), both accepted. A Router reads the destination IP address of each data packet and forwards it along the best path between separate networks — this inter-network forwarding is its defining Layer-3 function. A Gateway is the broader term for any node that connects two networks (often running different protocols) and translates/passes data between them; in most home and office setups the router itself acts as the default gateway. Because both terms genuinely describe a device that moves packets between two distinct networks, MPPSC's key credited both B and D.

MPPSC 2021 Prelims Paper-I · Question 28 of 100

Verified against the official question paper. Answer as per the official MPPSC answer key.

To transfer data packets between two computer networks, a ________ is used.

(a)Switch
(b)Router
(c)Brouter
(d)Gateway

Answer

B or D (both accepted by the official key)

Why

Correct — B (Router) or D (Gateway), both accepted. A Router reads the destination IP address of each data packet and forwards it along the best path between separate networks — this inter-network forwarding is its defining Layer-3 function. A Gateway is the broader term for any node that connects two networks (often running different protocols) and translates/passes data between them; in most home and office setups the router itself acts as the default gateway. Because both terms genuinely describe a device that moves packets between two distinct networks, MPPSC's key credited both B and D.

Why the others are wrong

(a)Switch — A switch connects devices WITHIN a single local network (LAN) using MAC addresses at Layer 2 — it does not forward packets between two separate networks.
(c)Brouter — A brouter is a hybrid bridge-router device, but it is not the standard term taught for basic inter-network packet transfer, so the key did not credit it.

Concept

Networking devices operate at different layers and connect different scopes. A Switch connects devices inside one LAN. A Router connects two or more distinct networks and forwards packets between them based on IP addresses (Layer 3). A Gateway is a network node that connects networks using different protocols or architectures, translating data as it crosses the boundary — the router in a home network is commonly also its gateway to the wider internet.

The trap in this question is treating 'Router' and 'Gateway' as mutually exclusive options when, in common usage and in many textbooks, a router performing protocol translation between dissimilar networks is described as a gateway — which is exactly why the commission accepted both.

Key facts

Switch: connects devices within one LAN, Layer 2, uses MAC addresses
Router: forwards packets between separate networks, Layer 3, uses IP addresses
Gateway: any node connecting two networks (possibly different protocols) and translating data between them
A home/office router commonly doubles as the network's default gateway

Which device connects two separate networks?

Switch→Connects devices within ONE network (LAN) — not between networks

Router→Forwards packets BETWEEN two networks using IP addresses

Brouter→Hybrid bridge+router — not the standard taught term here

Gateway→Connects two networks, translating data across the boundary

MPPSC's key credited both Router and Gateway, since both genuinely move data between two distinct networks.

Study next

OSI model layers and which device operates at which layerDifference between a bridge, switch, router and gatewayDefault gateway configuration in home/office networksLAN vs MAN vs WAN and the devices/topologies used in eachIP addressing and packet routing basics

Common traps

Treating 'Router' and 'Gateway' as strictly different devices when their functions genuinely overlap
Confusing a Switch (within one LAN) with a Router (between networks)

MPPSC frequently tests basic networking-device definitions ('which device does X') — know the layer and scope (within-LAN vs between-networks) for switch, router, bridge, and gateway.

Related PYQs

No directly related past PYQ was found.

Practice

practice — not a real PYQ
Which networking device operates at the Data Link layer and connects devices within a single LAN using MAC addresses?
- (a)Switch
- (b)Router
- (c)Gateway
- (d)Modem
Answer(a) Switch — Layer-2 device for intra-LAN connections.
practice — not a real PYQ
A device that connects two networks running different communication protocols, translating data as it passes between them, is called a:
- (a)Switch
- (b)Hub
- (c)Gateway
- (d)Repeater
Answer(c) Gateway.