NETWORKING...

IN Instance we create Bastion_server1 & 2 generally... It's for like Hopping from one server to the Another server. (Jump server) Public IP is Important..

A Security list in OCI is a VIRTUAL FIREWALL at the SUBNET Level. It contains INGRESS / EGRESS Rules that control

Incoming and Outgoing Network traffic...

FEATURES ::-

  1.) SOURCE ::- From where we want the Traffic..
  
  2.) Destination ::- where the Traffic is Going...

  3.) Port ::- Giving a Specific destination..(Network [port used for communications)
               such as 22 , 80 or 443.

               Http >> 80 >> Secure. ///  Https >> 443 >> Insecure.

  4.) Protocol ::- Rules & Regulations...
           
        1.) TCP :- Transmission control protocol..(Two way communication [sending/Receiving] the Traffic)

        2.) UDP :- User Datagram protocol..(one way communication [ only Receive the Traffic])

        3.) ICMP :- (PING) command to check the protocol. it's a two way communication (for testing purpose only)
                     To check the connections..(Not most reliable in industry.)

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RULES ::-

1.) INGRESS RULE ::- INCOMING TRAFFIC (INWARD) Allowing traffic from a particular source.

2.) EGRESS RULE ::- OUTGOING TRAFFIC (OUTWARD) Allowing a particular traffic from the port to the particular source.

Only on the SUBNETS LEVEL we can create the Security list..

THANKYOU !