A system, comprising: a receiver component configured to facilitate a cryptographic key exchange between two peer to peer devices; a channel variation component configured to determine at least one of a channel or interface over which the cryptographic key exchange occurred, and to change the at least one of the channel or interface so that a key verification occurs over a different channel or interface; and a verification component (106; 406; 806) configured to, using the different channel or interface, determine whether the cryptographic key exchange was secure or whether it was intercepted by one or more entities, wherein: the at least one channel or interface is implemented by a first internet protocol, IP-based network including a voice over IP, VoIP, network, and the different channel or interface is an established connection between the sender and a trusted entity via an SMS network, wherein the trusted entity is selected by the sender from a plurality of trusted entities and wherein the receiver does not support SMS, and the sender is configured to communicate a key verification with the selected one of the plurality of trusted entities via the SMS network, and the selected one of the plurality of trusted entities is configured to communicate the key verification with the receiver via an access point different from an access point of the first IP-based network connecting the sender and the receiver, and to send an acknowledgement to the sender via the SMS network if the key verification was successful, or to inform the sender via the SMS network if the key verification was not successful. a receiver component configured to facilitate a cryptographic key exchange between two peer to peer devices; a channel variation component configured to determine at least one of a channel or interface over which the cryptographic key exchange occurred, and to change the at least one of the channel or interface so that a key verification occurs over a different channel or interface; and a verification component (106; 406; 806) configured to, using the different channel or interface, determine whether the cryptographic key exchange was secure or whether it was intercepted by one or more entities, wherein: the at least one channel or interface is implemented by a first internet protocol, IP-based network including a voice over IP, VoIP, network, and the different channel or interface is an established connection between the sender and a trusted entity via an SMS network, wherein the trusted entity is selected by the sender from a plurality of trusted entities and wherein the receiver does not support SMS, and the sender is configured to communicate a key verification with the selected one of the plurality of trusted entities via the SMS network, and the selected one of the plurality of trusted entities is configured to communicate the key verification with the receiver via an access point different from an access point of the first IP-based network connecting the sender and the receiver, and to send an acknowledgement to the sender via the SMS network if the key verification was successful, or to inform the sender via the SMS network if the key verification was not successful. the at least one channel or interface is implemented by a first internet protocol, IP-based network including a voice over IP, VoIP, network, and the different channel or interface is an established connection between the sender and a trusted entity via an SMS network, wherein the trusted entity is selected by the sender from a plurality of trusted entities and wherein the receiver does not support SMS, and the sender is configured to communicate a key verification with the selected one of the plurality of trusted entities via the SMS network, and the selected one of the plurality of trusted entities is configured to communicate the key verification with the receiver via an access point different from an access point of the first IP-based network connecting the sender and the receiver, and to send an acknowledgement to the sender via the SMS network if the key verification was successful, or to inform the sender via the SMS network if the key verification was not successful.