15. A network device comprising: a memory to store one or more instructions; and a processor to execute the one or more instructions to: receive, via a first network connection, a key and information identifying a security level, of a plurality of security levels, from a different network device, the security level and the key being associated with a call transferred to the network device, by the different network device, via a second network connection that is different than the first network connection, the call being transferred using an access telephone number selected, from a plurality of access numbers, based on the security level, the security level being determined by the other network device prior to the security level being received by the network device, the security level and the key being received to perform speaker verification of a user associated with the call, associate the security level with the transferred call based on the key, perform, at a level corresponding to the security level and using a user profile that is associated with the user, the speaker verification of the user to generate a result, transfer, based on performing the speaker verification and via the second network connection, the call back to the different network device, and transmit, via the first network connection, the result and the key to the different network device, the different network device performing a transaction associated with the call based on the result.
19. The network device of claim 15 , where the key and the information identifying the security level are received via a packet switched network and the second network comprises a Public Switched Telephone Network (PSTN).