VPN

Description

VPN Interview Q & A Vol 1.0

Questions 100

Check the complete list of questions:

1. What is VPN?
2. What Security Vulnerabilities Are Addressed By VPN?
3. What is Authentication, Confidentiality & Integrity?
4. Can You List Some Items For A VPN Checklist From Deciding Whether To Use, Then Selecting, Then Deploying, then Maintaining VPN?
5. What is Symmetric and Asymmetric Encryption?
6. Which UDP ports should be open on a firewall to allow traffic from a L2TP/IPSEC based VPN clients to a PPTP VPN server on the inside?
7. What is IPsec VPN?
8. Is VPN A Long-term Solution Or A Short-term Stop Gap Kind Of Thing?
9. At what layer IPsec works?
10. What is name of cisco VPN Client installed on end devices?
11. What Are Unreasonable Expectations For VPN?
12. Does Cisco 4000 Series Router IOS support SSL VPN?
13. Name a major drawback of IPSec?
14. What is difference between GETVPN and FlexVPN?
15. What is the difference between Transport and Tunnel mode?
16. What are the three main security services that IPSec VPN provides?
17. Define Digital Signatures?
18. What Are Reasonable Expectations For A VPN?
19. What is Authorization?
20. Is There Market Penetration For These Products?
21. What Firewall Issues Are Relevant To VPN Selection And Deployment?
22. What is Site to Site and Remote Access VPN?
23. What are the 3 protocols used in IPSec?
24. Explain IPsec Protocol Headers?
25. How ESP & AH provides anti-replay protection?
26. What is IKE?
27. What Kind Of Resources (staff, Computational Muscle, Bandwidth, etc) Are Required for VPN Deployment, Usage, Maintenance?
28. At what protocol does IKE works?
29. Explain how IKE/ISAKMP Works?
30. Explain the messages exchange between the peers in IKE/ISAKMP?
31. What Is The Relationship Between VPN And Firewalls?
32. What is Diffie-Hellman?
33. How Diffie-Hellman works?
34. What are Security Associations?
35. What is Transform set?
36. What are Crypto access lists?
37. Are There Applications or Environments in Which VPNs Would Really Be Detrimental?
38. In a SSL VPN architecture, where are the session keys stored.
39. What are Crypto map?
40. What is SSL/TLS?
41. What is Split Tunneling? Why is it required?
42. How do you check the status of the tunnel’s phase 1 & 2?
43. What is IPsec Virtual Tunnel Interface?
44. What is L2F?
45. Are VPNs Used For Specific Kinds Of Applications Or Environments? If So, What Are Some Examples Of Where And Why VPNs Would Be Deployed?
46. What are the main components of VPN?
47. What is CBC ?
48. What is the difference between Static Crypto Maps and Dynamic Crypto Maps?
49. What is Cisco Easy VPN?
50. What are the 3 key methods to Control the access of VPN users and allowing access to selective resources?
51. What are the two IKE methods used by the IPsec protocol for secure tunnel negotiation?
52. What is the meaning of DAP wrt VPN ?
53. What are the two IKE methods used by the IPsec protocol for secure tunnel negotiation?
54. What is DMVPN?
55. What Crypto Issues Are Relevant In The VPN Context?
56. What is GRE in PPTP?
57. How does PPTP encapsulate data?
58. Can you explain CHAP?
59. Can you explain PAP?
60. what does PPTP use for encryption and authentication?
61. What are the three phases of DMVPN?
62. Explain Next Hop Resolution Protocol (NHRP)?
63. What is GRE?
64. Name a major drawback of both GRE & L2TP?
65. Who Are The Major Players In The Market?
66. What is SSL VPN?
67. How is SSL VPN different from IPsec VPN?
68. What are the different types of VPN?
69. At which Layer does SSL VPN operates?
70. By default, how many message pairs are exchanged in a typical IKEv2 connection?
71. What are different SSL VPN Modes?
72. What Are Some Of The Tough Questions To Pose To VPN Product Vendors?
73. Which method enables you to prevent user web traffic from traveling through the VPN tunnel?
74. Explain SSL Handshake?
75. what is the concept of HA and FA in VPN tunneling?
76. What is a connection profile?What details need to be entered which creating a connection profile?
77. What is significance of “priority” keyword in following command – “crypto dynamic-map name priority set ikev2 ipsec-proposal proposals“
78. What Kind Of Performance Issues Does VPN Raise?
79. What Security Vulnerabilities Are Unique To Or Heightened By VPN?
80. What are the available VPN Client IP Address Allocation methods is ASA?
81. An AnyConnect client uses which protocol through a VPN tunnel for automatic Certificate retrieval?
82. Which ports on firewall should be allowed for IPSEC Site to Site VPN?
83. Which ACL type is used with split-tunneling configuration?
84. What are 3 major components of Easy VPN?
85. During which phase does peer authentication occur?
86. What is difference between IKEv1 and IKEv2?
87. A user is complaining of being unable to open external or internal URLs directly or from the bookmark list. What could be the problem?
88. In a Cisco Remote-Access VPN Client , which files hold connection entry information?
89. What is the default MTU size set during installation of IPsec VPN Client on windows PC?
90. What is difference between MPLS and VPN?
91. What is difference between VPN and proxy?
92. Does Cisco ASA support VPN is Multi-context mode? If yes, then which Release onwards is the feature supported?
93. There is requirement to setup a VPN box in Data Center with different security Zones. Which Security Zone should the Internet/Public facing VPN box be connected to be reachable for Internet based users?
94. What is NAT Traversal? What is the purpose of using NAT-T?
95. Which IP protocol does AH and ESP headers use in IPSEC ?
96. Which type of VPN would you use if data has to be encrypted at the network 
layer?
97. What do we mean by VPN hairpinning?
98. What output after issuing “show crypto isakmp sa” command shows state as “MM_KEY_EXCH”, is this ideal state of VPN?
99. Which command is used to view the IKE Phase 1 management connections?
100. Which ports on firewall should be allowed for IPSEC Site to Site VPN?