Patent ID: 8737618
Filing Date: 2014-05-27
Classification: H04B,H04J,H04L

Abstract:
1. A method of encrypting and decrypting optical signals in an optical communication network, comprising: encrypting a series of optical signals using a pair of encryptors and an encryption key to form a series of encrypted optical signals; decrypting the series of encrypted optical signals; and updating the encryption key used to encrypt the series of optical signals, including using a first of the encryptors and a first encryption key to encrypt said series of optical signals; installing a new encryption key on a second of the encryptors; and when the new encryption key is installed on said second of the encryptors, switching the encrypting of the series of optical signals from the first of the encryptors to the second of the encryptors; wherein the installing the new encryption key on the second of the encryptors includes installing the new encryption key on the second of the encryptors while using the first of the encryptors and the first encryption key to encrypt the series of optical signals; wherein the decrypting includes using a pair of decryptors to decrypt the series of encrypted optical signals; and the updating the encryption key includes using a first of the decryptors and the first encryption key to decrypt the series of encrypted optical signals; installing the new encryption key on a second of the decryptors; and when the new encryption key is installed on the second of the decryptors, switching the decrypting of the series of encrypted optical signals from the first of the decryptors to the second of the decryptors; wherein the updating the encryption key further includes, according to synchronizing instructions, synchronizing the switching of the encrypting of the series of optical signals from the first of the encryptors to the second of the encryptors and the switching of the decrypting of the encrypted optical signals from the first of the decryptors to the second of the decryptors, whereby optical signals, of said series of optical signals, that are encrypted using the new encryption key are decrypted using the new encryption key only after said updating; wherein the encrypting includes using an encrypt side switch to direct optical signals, of the series of optical signals, selectively to only one of the first and second of the encryptors; and the decrypting includes using a decrypt side switch to direct encrypted optical signals, of said series of encrypted optical signals, selectively from only one of the first and second of the decryptors; wherein the updating the encryption key includes: encrypting the new encryption key using the first encryption key to form an encrypted key; and decrypting the encrypted key, on a receive side of the communications network, for installation in said second of the decryptors; and wherein the updating the encryption key further includes sending the encrypted key, along with the series of encrypted optical signals and the synchronizing instructions, from a transmit side of the communications network to the receive side of the communications network.