SSC CGL 2025 Tier-II · Paper-I, 19 January 2026 · Computer Knowledge Test · Question 15 of 150

We transcribed this text from the pictures of a candidate's response sheet for this paper; the answer is the key SSC marked with a green tick on that sheet. Solution last reviewed 11 September 2026.

Where this paper and its answers come from

SSC does not publish CGL question papers or a public answer key. This paper reaches us as a candidate's response sheet saved as pictures, so we transcribed the text from those pictures, and a second reader checked every question against them; where the layout carries meaning, we show the picture too. Each answer is the key SSC marked with a green tick on that sheet. SSC released a tentative key for challenge and later its final one, both only to candidates behind a login, and the sheet does not say which of the two it carries. UnlockIAS wrote the solutions.

What is the primary benefit of enabling encryption for data in transit on a network?

(a)It ensures that data is unreadable to attackers during transmission
(b)It protects against physical theft of devices
(c)It improves the overall speed of data transfer
(d)It prevents unauthorized users from accessing the network

Answer

Why

Correct — A. Encryption in transit protects data while it crosses the network. Anyone who captures the packets on the way sees only ciphertext, useless without the key.

TLS, the protocol behind HTTPS, states this as its confidentiality property: data sent over the channel is visible only to the endpoints → option (a).

Why the others are wrong

(b)
It protects against physical theft of devices — Theft of a laptop or phone threatens data at rest, stored on the device. That calls for storage encryption, such as full-disk encryption, not encryption of network traffic.
(c)
It improves the overall speed of data transfer — Encryption adds work: data is encrypted before sending and decrypted on arrival, and TLS first runs a handshake to agree keys. Speed is not what it buys.
(d)
It prevents unauthorized users from accessing the network — Keeping outsiders off a network is access control: logins, network authentication, firewalls. Transit encryption assumes traffic may be captured and makes it unreadable, but it does not decide who joins.

Concept

Data needs protecting in two states. In transit it is moving across a network, and protocols such as TLS encrypt it between the two endpoints. At rest it sits on a disk or phone, and storage encryption protects it there.

RFC 8446 describes TLS 1.3 as a secure channel with three properties: authentication, confidentiality and integrity. Its abstract says it is designed to prevent eavesdropping, tampering and message forgery.

Key facts

TLS 1.3 is specified in RFC 8446.
RFC 8446 lists three TLS properties: authentication, confidentiality and integrity.
Encryption in transit protects data moving across a network, while encryption at rest protects stored data.
NIST SP 800-111 covers storage encryption for end-user devices, including full-disk encryption.

Study next

TLS and HTTPSFull-disk encryption for data at restSymmetric and asymmetric keys in a TLS session

Common traps

Choosing 'prevents unauthorized users from accessing the network', when encryption leaves access decisions to authentication and firewalls.
Mixing up in-transit and at-rest protection: device theft is an at-rest problem.

Encryption also appears at 19 Jan 2026, 11:00 AM, Computer Knowledge Q.5 (S/MIME for e-mail) and at 19 Jan 2026, 11:00 AM, Computer Knowledge Q.20 (the key-distribution problem of symmetric encryption).

Related PYQs

No directly related past PYQ was found.

Topic: Basics of networking and cyber security — all 6 SSC CGL questions on it, every solved shift.