Firewalls are mandatory in any computer environment which you wish to call secure.   AWS establishes  the Firewall rules in the system via Security Groups and Ports.   Basically Security Groups define where traffic is permitted to go via established network ports.   Basic characteristics of security groups:

    1.  Security Groups are the Fundamental building block of network security (The Firewall) in AWS.

    2.  They define how traffic is allows into and out of all EC2 Instances.

    3.  Security groups only contain allowed rules.

    4.  Security groups reference IP or other security groups.

    5.  Security groups reference access Ports.

    6.  Security groups can reference both IPv4 and IPv6 networking

    7.  Security groups control both Inbound and Outbound traffic.

    8.  Security groups can be attached to multiple instances.

    9.  Security groups are dedicated to region/VPC

    10.  Security groups are independent of the EC2 Instances they support.

    11.  Best practice to have SSH access in its own security group.

    12.  If connections time out, this is a security group block.

    13.  If Connection refused error, this is the application error.

    14.  By default all inbound traffic is blocked.

    15.  By default all outbound traffic is allowed.

1.  The following is required before you create IAM user for your AWS Free Tier Account.

• An Active AWS Account with admin level permissions. 
  • Already created EC2 Instance.   

2.  Logon to AWS as an IAM user at URL:  https://signin.aws.amazon.com/

3.  From the Home Console type EC2 in the search bar, select the star next to EC2, and select EC2

4.  On the right hand menu bar select Instances.

5.  We currently have one EC2 Instances built out, click on the Instance ID you want.

6.  Select the Security tab and you will see the current security group for this session.   Retrieve the name of the security group attached to this Instance.  In this example the security group is  sg-0ce7968afc53f4bf6 (launch-wizard-1)

7.  On the left hand menu bar, scroll down to Network & Security ? Security Group.

8.  Click on the security group we found in the previous steps.  sg-0ce7968afc53f4bf6 (launch-wizard-1)

9.  On the Security group page we want to open the Inbound rules tab and select Edit inbound rules.

10.  On the Edit inbound rules page, select Add Rule

11.  We want to connect to this via HTTP and HTTPS, so we need to allow traffic on port 443 and 80 from any IP. Click Save rules.

12.  Back on the Security Group page you will see your new rules.

13.  This completes adding rules to a security group.

AWS has created multiple EC2 Instance types for various organizational applications.   An EC2 Instance is comparable to a Virtual Server in an on premises data center.   Depending on the use of the server, you will have varying CPU capacities, Memory allocations, number of Network Cards, different network speed allocations, and different type of storage allocated.  An EC2 Instance has the exact same types of different allocations.    An example of this is that a web server will not have the same ratio of CPU or Storage Capacity to network bandwidth that a database server will have.   You can view the standard type of AWS EC2 Instances at the URL:

https://aws.amazon.com/ec2/instance-types

Here you can see the Types of EC2 Instance available to you in the standard offering.   It is important to realize the a Type of Instance does not necessarily correlate to sizing.    Each Instance Type has a multitude of sizes offered.   The Instance types refer to the ratio or balance of server capacity to there intended use.   Note that within each Instance type you have a range of configuration capacity options.

The Instance Names can be broken down as follows:  We will use the example. M5.2xlarge

        –  m – is the instance class

        –  5 – the generation (improvement of class over time by AWS, normally changing with new hardware)

        –  2xlarge – size in the instance class

EC2 Instance Type

        –  General Purpose

   *  Balance between Compute, Memory and networking.

   *  Web servers

   *  Repositories.

                *  T and M Instances Classes

        –  Compute Optimized

   *  Intense computing uses

     *  Batch Processing

     *  Media manipulation

     *  High performance web servers

     *  HPC – High performing Computing

     *  Scientific Modeling

     *  Gaming servers

                *  C Instances Class

        –  Memory Optimized

     *  For processing large data sets in memory

                *  In-memory relation database

                          *  Distributed web cache

                            *  Business Intelligence – Reporting

                            *  Big unstructured data

                            *  R, X, Z Instances Classes

        –  Accelerated Computing

                *  Hardware accelerated comput

                *  Graphics systems

                *  Mathematical calculation system

                *  Data pattern matching

                *  P, G, T, D, F, V Instances Classes

        –  Storage Optimized

                *  Storage related computing – High Reads and Writes.

                *  OLTP systems

                *  Relation Databases

                *  Cache Database

                *  Data Warehouses

                *  Distributed file systems

                *  I and D Instances Classes

        –  HPC Optimized

                *  High Performance Computer offering

                *  Engineering

                *  Weather modeling

                *  molecular modeling

                *  H Instance Class

•