getObject retrieves the SoftLayer_Network_Customer_Subnet object whose ID number corresponds to the ID number of the init parameter passed to the SoftLayer_Network_Customer_Subnet service. You can only retrieve the subnet whose account matches the account that your portal user is assigned to.
Every Customer subnet is defined in the SoftLayer_Network_Customer_Subnet service. SoftLayer keeps track of subnets outside of the SoftLayer Network that are associated to SoftLayer subnets or systems.
For example, customer subnets are tracked for proper management of network tunnels. This service allows for managing subnets on the remote end of the network tunnel.