Patent ID: 9712323
Date: 2017-07-18
CPC Classifications: H04L

Claim:
1. A method for detection of an unauthorized entity in a layer 2 communication system, comprising: obtaining a secret string by a first network element; generating a random number by the first network element; computing a first cryptographic result by the first network element, the first cryptographic result based on a cryptographic function, the secret string, and the random number; transmitting, by the first network element, a first packet that includes the random number to a second network element using an IEEE Standard 802.3 layer 2 single-hop packet terminating protocol, wherein the layer 2 single-hop packet terminating protocol is a link Operations, Administration, and Maintenance (OAM) protocol; receiving a second packet including a second cryptographic result at the first network element; terminating transmission to the second network element when a second cryptographic result is different from the first cryptographic result; terminating transmission to the second network element when the second packet is not received in a configured time; and indicating, by the first network element, the presence of an unauthorized entity when the second cryptographic result is different from the first cryptographic result or when the second packet is not received in a configured time.