156-315.81.20 Advanced VPN Design Practice Question
A company's Security Management Server manages 12 gateways. The administrator has created a Star VPN community named 'StarCommunity' and a Mesh VPN community named 'MeshCommunity'. Gateway A belongs to both communities. In the community properties, 'StarCommunity' is configured to use IKEv1 only, while 'MeshCommunity' is configured to use IKEv2 only. A new site-to-site tunnel is attempted between Gateway A and Gateway B, where Gateway B belongs only to 'MeshCommunity'. Which statement describes the IKE version negotiation for this tunnel?
⚠ Common exam trap
The trap here is assuming that a gateway's multiple community memberships create a conflict or that the first or alphabetically first community wins, rather than using the community shared with the specific remote peer.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The tunnel will use IKEv2 because the common community between the two gateways is MeshCommunity, which is configured for IKEv2.
When a gateway belongs to multiple VPN communities, the encryption method for a specific tunnel is taken from the community that is shared with the remote peer. Here, Gateway A and Gateway B share only MeshCommunity, which is configured for IKEv2. Therefore, the tunnel negotiates IKEv2. The other options incorrectly assume alphabetical priority, configuration order, or a conflict that does not exist.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
The tunnel will use IKEv2 because the common community between the two gateways is MeshCommunity, which is configured for IKEv2.
Why this is correct
Gateway A and Gateway B share only the MeshCommunity. Check Point uses the encryption method configured in the community that both peers belong to. Since MeshCommunity is set to IKEv2 only, the tunnel will negotiate IKEv2. This is correct because the overlapping community determines the IKE version, not the gateway's other memberships.
- ✗
The tunnel will fail because Gateway A belongs to two communities with conflicting IKE versions and cannot determine which to use.
Why it's wrong here
Check Point gateways can belong to multiple VPN communities, and the IKE version is determined per tunnel based on the community shared with the remote peer. There is no global conflict; the gateway uses the community that matches the remote peer's membership. Thus the tunnel will succeed using the shared community's settings, not fail.
- ✗
The tunnel will use IKEv1 because Gateway A will prioritize the community with the lowest alphabetical name.
Why it's wrong here
There is no alphabetical priority for VPN communities. The IKE version used is determined by the community that both peers share and its configured encryption method. Since Gateway B belongs only to MeshCommunity, which is IKEv2-only, the tunnel cannot use IKEv1. The statement misrepresents how community membership and IKE version selection work in Check Point.
- ✗
The tunnel will use IKEv1 because Gateway A's first configured community is StarCommunity, which takes precedence.
Why it's wrong here
Community precedence is not based on configuration order. The IKE version is derived from the community that both gateways belong to. Since Gateway B is not in StarCommunity, that community is irrelevant. The tunnel uses MeshCommunity's IKEv2 setting, so this option is incorrect.
Quick reference
VPN Protocol Comparison
| Protocol | Port | Encryption | Authentication | Use Case |
|---|---|---|---|---|
| IKEv2 / IPsec | UDP 500 / 4500 | AES-256 | Certificates / PSK | Site-to-site & remote access |
| SSL / TLS VPN | TCP 443 | TLS 1.3 | Certificates / MFA | Clientless remote access |
| L2TP / IPsec | UDP 1701 | AES (IPsec) | PSK / Certificates | Legacy remote access |
| WireGuard | UDP 51820 | ChaCha20 | Public keys | Modern high-performance VPN |
| PPTP | TCP 1723 | MPPE (weak) | MS-CHAPv2 | Legacy — avoid in production |
PPTP is considered insecure. IKEv2/IPsec and SSL VPN are the current recommended options.
About these practice questions
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JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Check Point exam blueprint
This 156-315.81.20 practice question is part of Courseiva's free Check Point certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 156-315.81.20 exam.