350-701 · Question #415
An engineer is trying to decide between using L2TP or GRE over IPsec for their site-to-site VPN implementation. What must be understood before choosing a solution?
The correct answer is A. L2TP is an IP packet encapsulation protocol, and GRE over IPsec is a tunneling protocol.. L2TP is a Layer 2 protocol and GRE is a layer 3. IPSEC works at layer 3. As per the options, L2TP is an ip packet encapsulation (since its a layer 2 protocol), and therefore seems to be the best feasible correct option amongst the given choices; GRE over IPSEc is a tunnelling pro
Question
An engineer is trying to decide between using L2TP or GRE over IPsec for their site-to-site VPN implementation. What must be understood before choosing a solution?
Options
- AL2TP is an IP packet encapsulation protocol, and GRE over IPsec is a tunneling protocol.
- BL2TP uses TCP port 47 and GRE over IPsec uses UDP port 1701.
- CGRE over IPsec adds its own header, and L2TP does not.
- DGRE over IPsec cannot be used as a standalone protocol, and L2TP can.
How the community answered
(50 responses)- A88% (44)
- B4% (2)
- C6% (3)
- D2% (1)
Explanation
L2TP is a Layer 2 protocol and GRE is a layer 3. IPSEC works at layer 3. As per the options, L2TP is an ip packet encapsulation (since its a layer 2 protocol), and therefore seems to be the best feasible correct option amongst the given choices; GRE over IPSEc is a tunnelling protocol (basically used for VPN). As per the question, which is asking in regards to "site to site VPN", L2TP cannot be used alone, you will need IPSEC at layer 3 whereas GRE over IPSEC can be used to achieve that.
Topics
Community Discussion
No community discussion yet for this question.