Creates a subnet in an existing VPC.
             
 Declaration Syntax
 Declaration Syntax| C# | 
public CreateSubnetResponse CreateSubnet( CreateSubnetRequest request )
 Parameters
 Parameters- request (CreateSubnetRequest)
- Create Subnet request
 Return Value
 Return ValueCreate Subnet  Response from the service
 Remarks
 Remarks
             You can create up to 20 subnets in a VPC. If you add more than one subnet to a
             VPC, they're set up in a star topology with a logical router in the middle.
             If you feel you need more than 20 subnets, you can request more by going
             to http://aws.amazon.com/contact-us/vpc-request/.
             
             When you create each subnet, you provide the VPC ID and the CIDR block you
             want for the subnet. Once you create a subnet, you can't change its CIDR block.
             The subnet's CIDR block can be the same as the VPC's CIDR block (assuming you
             want only a single subnet in the VPC), or a subset of the VPC's CIDR block. If you
             create more than one subnet in a VPC, the subnets' CIDR blocks must not overlap.
             The smallest subnet (and VPC) you can create uses a /28 netmask (16 IP
             addresses), and the largest uses a /18 netmask (16,384 IP addresses).
            
             *Important*
            
             AWS reserves both the first four and the last IP address in each subnet's CIDR block.
             They're not available for use.
            
             AWS might delete any subnet you create with this operation if you leave it inactive
             for an extended period of time (inactive means that there are no running Amazon
             EC2 instances in the subnet).
             
 Exceptions
 Exceptions| Exception | Condition | 
|---|---|
| WebException | |
| AmazonEC2Exception |