When configuring IPsec VPN on a Cisco IOS firewall what para

When configuring IPsec VPN on a Cisco IOS firewall, what parameters can be defined? Describe how one of the parameters affects the VPN function and security

Solution

When configuring IPsec VPN on a Cisco IOS firewall, the following parameters can be defined and also their effects can be explained as below:
1)Security Parameter Index (SPI)
Security parameter index is the number which consists of destination IP address and security protocol that identifies a particular security association uniquely.
2)Transform
Transform is the list of operations which are perofrmed on dataflow to support data authentication, data confidentiality and data compression.
3)Security Association
Security association describes how two or more entities use the security services in AH or ESP to communicate securely on behalf of a particular data flow.
4)Tunnel
Tunnel is a secure communication path between two devices, eg two routers.
5)Peer
Peer refers to a router or other device that is connected to IPSec.
6)Data Confidentiality
Data confidentiality is a security mechanism which protect data from unauthorize access.
7)Data Flow
Data flow is a combination of traffic, identified by a combination of source address, destination address, IP next protocol field, source ports and destination ports, where the protocol and port fields can have the values of any.
8)Anti-Replay
Anti-replay is a security mechanism where the receiver rejects old or duplicate packets in order to protect itself against replay attacks.