Patent ID: 8990569
Filing Date: 2015-03-24
Classification: H04L

Abstract:
1. A method comprising: receiving, by a registration device, a register message from a first client device; transmitting, by the registration device and in response to the register message, a digital certificate including a public key associated with the registration device to the first client device; receiving, by the registration device, a secure session setup message that includes a header that comprises an encrypted key generating value from the first client device, wherein the encrypted key generating value is encrypted using the public key associated with the registration device; decrypting, by the registration device, the encrypted key generating value using a private key associated with the registration device; generating, by the registration device, a temporary session key associated with the first client device based on the key generating value; identifying, by the registration device, a first IP address associated with a second client device; generating, by the registration device, a second temporary session key associated with the second client device based on a second key generating value received from the second client device; receiving, by the registration device, a secure session invitation message from the first client device requesting a secure communication with the second client device; identifying, by the registration device, a second IP address associated with the first device; generating, by the registration device, a master session key; encrypting, by the registration device, the master session key using the second temporary session key associated with the second client device; generating, by the registration device, a modified secure session invitation message that includes a header that includes the IP address of the second device and the encrypted master session key; transmitting, by the registration device, the encrypted master session key to the second client device, within the modified the secure session invitation message for decrypting by the second client device; receiving, by the registration device, an acceptance message from the second client device; generating, by the registration device, a modified acceptance message that includes a header that includes the IP address of the first device and the encrypted master session key; and transmitting, by the registration device, the encrypted master session key to the first client device within the modified acceptance message.