@sg = $ec2->describe_security_groups(@group_ids)

@sg = $ec2->describe_security_groups(%args);

@sg = $ec2->describe_security_groups(\%filters);

In the named-argument form you can provide the following optional arguments:

 -group_name      A single group name or an arrayref containing a list
                   of names

 -name            Shorter version of -group_name

 -group_id        A single group id (i.e. 'sg-12345') or an arrayref
                   containing a list of ids

 -filter          Filter on tags and other attributes.

The -filter argument name can be omitted if there are no other arguments you wish to pass.

The full list of security group filters can be found at: http://docs.amazonwebservices.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeSecurityGroups.html

$group = $ec2->create_security_group(-group_name=>$name, -group_description=>$description, -vpc_id => $vpc_id )

 -group_name              Name of the security group (required)
 -group_description       Description of the security group (required)
 -vpc_id                  Virtual private cloud security group ID
                           (required for VPC security groups)

For convenience, you may use -name and -description as aliases for -group_name and -group_description respectively.

If succcessful, the method returns an object of type VM::EC2::SecurityGroup.

$boolean = $ec2->delete_security_group($group_id)

$boolean = $ec2->delete_security_group(-group_id => $group_id, -group_name => $name);

 -group_name              Name of the security group
 -group_id                ID of the security group

Either -group_name or -group_id is required. In the single-argument form, the method deletes the security group given by its id.

If succcessful, the method returns true.

$boolean = $ec2->update_security_group($security_group)

For details, see VM::EC2::SecurityGroup. Here is a brief summary:

 $sg = $ec2->create_security_group(-name=>'MyGroup',-description=>'Example group');

 # TCP on port 80 for the indicated address ranges
 $sg->authorize_incoming(-protocol  => 'tcp',
                         -port      => 80,
                         -source_ip => ['192.168.2.0/24','192.168.2.1/24'});

 # TCP on ports 22 and 23 from anyone
 $sg->authorize_incoming(-protocol  => 'tcp',
                         -port      => '22..23',
                         -source_ip => '0.0.0.0/0');

 # ICMP on echo (ping) port from anyone
 $sg->authorize_incoming(-protocol  => 'icmp',
                         -port      => -1,
                         -source_ip => '0.0.0.0/0');

 # TCP to port 25 (mail) from instances belonging to
 # the "Mail relay" group belonging to user 12345678.
 $sg->authorize_incoming(-protocol  => 'tcp',
                         -port      => 25,
                         -group     => '12345678/Mail relay');

 $result = $ec2->update_security_group($sg);

or more simply:

 $result = $sg->update();