What do the following statements in an extended access list accomplish?

What do the following statements in an extended access list accomplish? access-list 101 deny TCP 172.16.4.0 0.0.0.255 172.16.3.0 0.0.0.255 eq 21 access-list 101 deny TCP 172.16.4.0 0.0.0.255 172.16.3.0 0.0.0.255 eq 20 access-list 101 permit TCP 172.16.4.0 0.0.0.255 0.0.0.0 255.255.255.255 A. This will block ftp traffic. B. This will block http traffic. C. This will permit [...]

Cisco routers use wildcard masking to identify how to check or ignore corresponding IP address bits. What does setting a wildcard mask bit to 0 cause the router to do?

Cisco routers use wildcard masking to identify how to check or ignore corresponding IP address bits. What does setting a wildcard mask bit to 0 cause the router to do? A. It tells the router to check the corresponding bit value. B. It tells the router to ignore the corresponding bit value. C. It tells [...]

Can you define in short what VPN is?

Can you define in short what VPN is? ->A Virtual Private Network (VPN) is a network technology that creates a secure network connection over a public network such as the Internet or a private network owned by a service provider. Large corporations, educational institutions, and government agencies use VPN technology to enable remote users to [...]

Can you explain what IPSec is

Can you explain what IPSec is ->ipsec is a suite of protocols which ensure the following: 1-confidentiality of data 2-integrity of data 3-anti-replay of data 4-non-repudiation contains the main cryptographic algorithms used in securing traffic between two networks over an un trusted network