What does VPN stand for?
VPN stands for Virtual Private Network. An encrypted tunnel over an untrusted network that connects remote users or sites to a private network. It is commonly built with IPSec or TLS.
A VPN builds an encrypted tunnel across a network you do not trust, usually the internet. A remote-access VPN connects one user's device to the company network; a site-to-site VPN joins two networks permanently. The common technologies are IPsec and TLS. With a full tunnel all of the device's traffic goes through the VPN; with a split tunnel only traffic for company addresses does.
VPN in practice: an example
A consultant in a hotel opens the VPN client. Traffic to the file server travels encrypted to the company's gateway and appears to come from an internal address. With split tunnelling her video streaming goes straight to the internet, which saves bandwidth but bypasses the company's web filtering.
What VPN is confused with
VPN vs proxy: what is the difference?
A proxy relays traffic for one application or protocol and does not necessarily encrypt it. A VPN encrypts and carries traffic at the network level.
VPN vs ZTNA: what is the difference?
A VPN puts the user on the network. ZTNA gives access to one application at a time and keeps checking the user and device. What ZTNA stands for
Which exams cover VPN?
VPN is on the official CompTIA acronym list for three of the four exams covered here.
- Security+ SY0-801: 2.3 (Threats, Vulnerabilities, and Attacks); 3.2 (Security Architecture).
- Network+ N10-009: 1.0 (Networking Concepts); 3.0 (Network Operations).
- A+ 220-1201 and 220-1202: 220-1201 2.0 (Networking); 220-1202 1.0 (Operating Systems); 220-1202 4.0 (Operational Procedures).
Each number is a CompTIA exam objective and the name in brackets is its domain. The exam puts the term in a scenario; it does not ask you to recite the expansion.
Check yourself: two practice questions
Written by CertSprint for this page. They are not taken from any exam.
1. Two offices need a permanent encrypted link so that their networks behave as one. What should be configured?
- A remote-access VPN on every laptop
- A site-to-site VPN between the gateways
- A guest wireless network
- A shared DHCP scope
Show the answer
B. A site-to-site VPN between the gateways. A site-to-site VPN connects two networks through their gateways. Users do nothing; routing sends inter-office traffic into the tunnel.
2. Security policy requires that all internet traffic from remote laptops passes through company filtering. Which VPN setting meets it?
- Split tunnel
- Full tunnel
- No tunnel
- Clientless mode only
Show the answer
B. Full tunnel. A full tunnel sends everything through the company gateway, where filtering applies. Split tunnelling lets internet traffic bypass it.
Sources: NIST glossary: virtual private network; NIST SP 800-77 Rev. 1, Guide to IPsec VPNs. The acronym and its expansion come from CompTIA's official acronym lists, linked from each exam glossary above. The explanation, example and questions are CertSprint's own, checked against these sources on 11 November 2026.