Which two secure authentication types can be used with OSPF authentication on Cisco IOS routers? (Choose two.)MD5SHAAESRSA digital certificatesCleartext

1. Break Down the Problem

We need to identify two secure authentication types that can be used with OSPF (Open Shortest Path First) authentication on Cisco IOS routers. The options provided are:

• MD5
• SHA
• AES
• RSA digital certificates
• Cleartext

2. Relevant Concepts

OSPF supports different authentication types to ensure secure routing updates between routers. Secure authentication methods improve the integrity and confidentiality of routing information.

3. Analysis and Detail

• MD5: This is a widely used hashing algorithm which ensures that the OSPF routing information is validated using a password-based mechanism. It provides a secure way of authenticating OSPF messages but is not as robust as newer standards.

• SHA: This stands for Secure Hash Algorithm, which is more secure than MD5. It provides a similar hashing mechanism for authenticating OSPF messages and is generally recommended for better security.

• AES: Advanced Encryption Standard is primarily used for data encryption rather than authentication. Therefore, it is not directly used for OSPF authentication.

• RSA digital certificates: While RSA is a type of public-key cryptography that can be used for authentication, it typically functions differently in the context of dynamic and secure key exchange as opposed to being a direct method of authenticating OSPF itself.

• Cleartext: This is the absence of any encryption or hashing and thus is not considered secure.

4. Verify and Summarize

In conclusion, the secure authentication types appropriate for OSPF authentication on Cisco IOS routers are MD5 and SHA. Both methods enhance the security of OSPF by providing means to authenticate routing messages.

Final Answer

The two secure authentication types that can be used with OSPF authentication on Cisco IOS routers are MD5 and SHA.