Patent Description:
The present invention is set out in the independent claims. Some implementations described herein relate to a method. The method may include identifying, by a first network device, a MACsec session between the first network device and a second network device, where the MACsec session utilizes a connectivity association key (CAK). The method may include determining, by the first network device and using a key derivation function (KDF) and one or more KDF input parameters, an additional CAK. The method may include encrypting, by the first network device, at least one of the one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information. The method may include sending, by the first network device and to the second network device, a first message that includes the encrypted KDF input information. The method may include receiving, by the first network device, from the second network device, and based on sending the first message, a second message that includes a checksum value. The method may include determining, by the first network device and based on the checksum value, that the second network device has determined the additional CAK. The method may include communicating, by the first network device and with the second network device, to cause the MACsec session to utilize the additional CAK.

Some implementations described herein relate to a first network device. The first network device may include one or more memories and one or more processors. The first network device may be configured to determine, using a KDF and one or more KDF input parameters, a CAK for a MACsec session between the first network device and a second network device. The first network device may be configured to encrypt at least one of the one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information. The first network device may be configured to send, to the second network device, a first message that includes the encrypted KDF input information. The first network device may be configured to receive, from the second network device and based on sending the first message, a second message. The first network device may be configured to communicate, with the second network device and based on the second message, to cause the MACsec session to utilize the CAK.

Some implementations described herein relate to a computer-readable medium that encodes a set of instructions for a second network device. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to receive, from a first network device, a first message that includes encrypted KDF input information. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to process the first message to determine the encrypted KDF input information. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to decrypt the encrypted KDF input information to determine at least one of one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to determine, based on determining at least one of the one or more KDF input parameters or the KDF identification information that identifies the KDF and the one or more KDF input parameters, a CAK for a MACsec session between the first network device and the second network device. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to determine, based on the CAK, a checksum value. The set of instructions, when executed by one or more processors of the second network device, may cause the second network device to send, to the first network device, a second message that includes the checksum value.

The MACsec protocol enables two network devices to securely communicate via a MACsec session between the network devices. The MACsec session utilizes a CAK to enable secure communication between the network devices. For example, each of the network devices may derive and/or generate other keys, such as a secure association key (SAK) and/or a key encryption key (KEK), to encrypt communications between the network devices. While the keys derived from the CAK can be automatically updated and/or changed at any time (by the network devices), a change to a CAK requires a manual intervention by a system administrator of the network devices. In some cases, the system administrator may manually configure the network devices with a "keychain" of CAKs and a schedule indicating when each CAK is to be utilized by the MACsec session. However, this requires a use of computing resources (e.g., processing resources, memory resources, communication resources, and/or power resources, among other examples) of the network devices to maintain the keychain and to ensure that the network devices are synchronized (e.g., to ensure that the network devices are using the same CAK at the same time). Further, after all the CAKs in the keychain have been used, the system administrator again has to manually configure the network devices with a new keychain of CAKs.

Some implementations described herein provide a first network device and a second network device that are connected via a MACsec session. The first network device may determine a new CAK for the MACsec session (e.g., on a scheduled basis, or on a triggered basis, such as based on a security threat determination). The first network device may use a KDF and one or more KDF input parameters to generate the new CAK and, accordingly, may encrypt the one or more KDF input parameters and/or KDF identification information that identifies the KDF and/or the one or more KDF input parameters to generate encrypted KDF input information. The first network device may send, to the second network device, a first message (e.g., a MACsec key agreement protocol data unit (MKPDU)) that includes the encrypted KDF input information. The second network device may decrypt the encrypted KDF input information of the first message to determine the one or more KDF input parameters and/or the KDF identification information. Accordingly, the second network device may use the one or more KDF input parameters and/or the KDF identification information to determine the new CAK (e.g., the same CAK determined by the first network device). The second network device then may determine a checksum value (e.g., based on the new CAK) and may send, to the first network device, a second message (e.g., an MKPDU) that includes the checksum value. The first network device may validate the checksum value of the second message (e.g., by determining an additional checksum value based on the new CAK that was generated by the first network device and determining that the checksum value and the additional checksum value match). Accordingly, the first network device may determine that the second network device has determined the new CAK and the first network device and the second network device then may communicate to cause the MACsec session to utilize the new CAK (e.g., because both the first network device and the second network device have determined the same new CAK for the MACsec session).

In this way, some implementations described herein enable automatic generation and update of CAKs for MACsec sessions. Accordingly, the first network device and the second network device do not need to be manually configured (e.g., by a system administrator) with new CAKs. Additionally, the first network device and the second network device do not need to use computing resources (e.g., processing resources, memory resources, communication resources, and/or power resources, among other examples) to maintain a keychain of CAKs and/or to ensure that the first network device and the second network device are synchronized (e.g., because the first network device and the second network device may determine and utilize a new CAK regardless of schedule and/or synchronization of the first network device and the second network device).

<FIG> are diagrams of one or more example implementations <NUM> described herein. Example implementation(s) <NUM> may include a first network device and a second network device in a network. The first network device and the second network device are described in more detail below in connection with <FIG>.

As shown in <FIG>, and by reference number <NUM>, the first network device and the second network device may establish a MACsec session (also referred to as a MACsec key agreement (MKA) session). For example, the first network device and the second network device may perform a handshake procedure, in which the network devices exchange information to establish the MACsec session. The MACsec session may utilize a CAK. For example, the first network device and/or the second network device may process the CAK to generate and/or determine one or more encryption keys, such as a SAK or KEK, to be used to encrypt and/or decrypt information that is to be communicated between the first network device and the second network device via the MACsec session. The MACsec session may have a name (e.g., "ABCD"), also referred to as a CAK name or a connectivity association key name (CKN), to enable the first network device and the second network device to identify the MACsec session and differentiate the MACsec session from other MACsec sessions associated with the network devices.

As shown by reference number <NUM>, the first network device and the second network device may communicate messages via the MACsec session. In some implementations, the messages may be "hello" messages (also referred to as "keep-alive" messages) that the first network device and/or the second network device periodically send to each other to maintain the MACsec session. For example, the messages may be MKA protocol data unit (MKPDU) messages, each of which includes a name field (e.g., a CAK name field or a CKN field) that identifies the name of the MACsec session (e.g., to indicate to a recipient network device that the MACsec session should be maintained).

As shown in <FIG>, and by reference number <NUM>, the first network device may identify the MACsec session (e.g., as part of a process to update the CAK for the MACsec session). For example, the first network device, on a scheduled basis, on an on-demand basis, on a triggered basis, or on an ad-hoc basis, among other examples, may identify the MACsec session to enable the first network device to update the CAK of the MACsec session.

As shown by reference number <NUM>, the first network device may determine an additional CAK (e.g., a "new" CAK or an "updated" CAK) to be utilized by the MACsec session. For example, the first network device may identify (e.g., generate or select) and use one or more key derivation function (KDF) input parameters to generate the additional CAK. The one or more KDF input parameters may include, for example, a KDF parameter (e.g., that indicates a KDF to be used to generate the additional CAK), a key parameter to be used by the KDF, a label parameter to be used by the KDF, and/or a context parameter to be used by the KDF. Accordingly, the first network device may use the KDF (e.g., as indicated by the one or more KDF parameters), and/or one or more other parameters of the one or more KDF input parameters, to generate the additional CAK. In a representative example, the first network device may use a KDF "KDF1" with a key "KEY1," a label "LABEL1," and a context "VAR1" to generate the additional CAK.

As shown by reference number <NUM>, the first network device may encrypt the one or more KDF input parameters and/or KDF identification information that identifies the KDF and/or the one or more KDF input parameters to generate encrypted KDF input information. For example, the first network device may use an encryption key associated with the CAK (e.g., the "current" CAK of the MACsec session), such as a secure association key (SAK) or a key encryption key (KEK), to encrypt the one or more KDF input parameters to generate the encrypted KDF input information. With reference to the representative example above, the first network device may encrypt a string "KDF1#KEY1#LABEL1#VAR1," which is a concatenation of the one or more KDF input parameters, to generate the encrypted KDF input information "2AB*^&GH JL(KB*HBN".

As shown by reference number <NUM>, the first network device may send, to the second network device, a first message that includes the encrypted KDF information. The first message may be, for example, an MKPDU (e.g., that is associated with the MACsec session) and the encrypted KDF information may be included in a name field (e.g., a CAK name field or a CKN field) of the MKPDU. In some implementations, the first message may include an indicator (e.g., one or more characters, such as an "@" character) indicating that the first message includes the encrypted KDF input information. With reference to the representative example, the name field of the first message may include "ABCD@2AB*^&GH JL(KB*HBN," where "ABCD" is the name of the MACsec session, "@" is the indicator indicating that the first message includes the encrypted KDF input information, and "2AB*^&GH JL(KB*HBN" is the encrypted KDF input information.

As shown in <FIG>, and by reference number <NUM>, the second network device may determine the encrypted KDF input information (e.g., based on receiving the first message from the first network device). In some implementations, the second network device may process (e.g., parse and/or read) the first message to determine the encrypted KDF input information. For example, the second network device may read the name field of the first message to determine the encrypted KDF input information. As another example, the second network device may parse the name field of the first message to identify the indicator indicating that the first message includes the encrypted KDF input information (e.g., the "@" character) and may thereby identify the encrypted KDF input information. With reference to the representative example, the second network device may process the first message to identify the "@" indicator and may thereby identify the "2AB*^&GH JL(KB*HBN" encrypted KDF input information.

As shown by reference number <NUM>, the second network device may determine the one or more KDF input parameters and/or the KDF identification information (e.g., that identifies the KDF and/or the one or more KDF input parameters). In some implementations, the second network device may decrypt the encrypted KDF information (e.g., that the second network device determined based on the first message) to determine the one or more KDF input parameters and/or the KDF identification information. For example, the second network device may use an encryption key associated with the CAK (e.g., the current CAK of the MACsec session), such as the SAK or the KEK (e.g., that the first network device used to generate the encrypted KDF information), to decrypt the encrypted KDF information and thereby determine the one or more KDF input parameters and/or the KDF identification information. In some implementations, the second network device may decrypt the encrypted KDF information based on the indicator in the first message that indicates that the first message includes the encrypted KDF input information. For example, the second device may decrypt the encrypted KDF information based on identifying the indicator in the first message (e.g., because the indicator indicates that the encrypted KDF input information is included in the name field of the first message, positioned after the indicator within the name field). With reference to the representative example, the second network device may decrypt the encrypted KDF input information "2AB*^&GH JL(KB*HBN" to determine the "KDF1#KEY1#LABEL1#VAR1" string that is a concatenation of the one or more KDF input parameters.

As shown by reference number <NUM>, the second network device may determine the additional CAK (e.g., the new CAK or the updated CAK) that is to be utilized by the MACsec session. For example, the second network device may use the KDF and the one or more KDF input parameters to generate the additional CAK (e.g., use the KDF indicated by the KDF parameter, of the one or more KDF input parameters, and/or one or more other parameters of the one or more KDF input parameters) to generate the additional CAK. With reference to the representative example, the second network device may use the KDF "KDF1" with the key "KEY1," the label "LABEL1," and the context "VAR1" to generate the additional CAK. Additionally, or alternatively, the second network device may identify, based on the KDF identification information, the KDF and/or the one or more KDF input parameters and may thereby use the KDF and/or the one or more KDF input parameters to generate the additional CAK.

As shown by reference number <NUM>, the second network device may determine a checksum value. For example, the second network device may process (e.g., using a hashing technique or a checksum technique) the additional CAK to determine the checksum value. Accordingly, the checksum value is associated with the second network device determining the additional CAK based on the encrypted KDF input information (e.g., that was included in the first message that was received by the second network device). With reference to the representative example, the second network device may process the additional CAK to generate the checksum value "CHKSUM34539AB".

As shown by reference number <NUM>, the second network device may send, to the first network device, a second message that includes the checksum value. The second message may be, for example, an MKPDU (e.g., that is associated with the MACsec session) and the encrypted checksum value may be included in a name field (e.g., a CAK name field or a CKN field) of the MKPDU. In some implementations, the second message includes an indicator (e.g., one or more characters, such as a "#" character) indicating that the second message includes the checksum value. With reference to the representative example, the name field of the second message may include "ABCD#CHKSUM34539AB," where "ABCD" is the name of the MACsec session, "#" is the indicator indicating that the second message includes the checksum value, and "CHKSUM34539AB" is the checksum value.

As shown in <FIG>, and by reference number <NUM>, the first network device may determine the checksum value (e.g., based on receiving the second message from the second network device). In some implementations, the first network device may process (e.g., parse and/or read) the second message to determine the checksum value. For example, the first network device may read the name field of the second message to determine the checksum value. As another example, the first network device may parse the name field of the second message to identify the indicator indicating that the second message includes the checksum value (e.g., the "#" character) and may thereby identify the checksum value. With reference to the representative example, the first network device may process the second message to identify the "#" indicator and may thereby identify the "CHKSUM34539AB" checksum value.

As shown by reference number <NUM>, the first network device may determine an additional checksum value. For example, the first network device may process (e.g., using a hashing technique or a checksum technique) the additional CAK (e.g., determined by the first network device, as described herein in relation to <FIG> and reference number <NUM>) to determine the additional checksum value. With reference to the representative example, the first network device may process the additional CAK to generate the checksum value "CHKSUM34539AB".

As shown by reference number <NUM>, the first network device may validate the checksum value (e.g., based on the additional checksum value). For example, the first network device may compare the checksum value and the additional checksum value. The first network device may validate the checksum value when the first network device determines, based on the comparison, that the checksum value matches (e.g., is equal to) the additional checksum value. The first network device may thereby determine that the second network device has determined the additional CAK (and may therefore perform one or more additional processing steps described herein). Alternatively, the first network device may not validate the checksum value when the first network device determines, based on the comparison, that the checksum value does not match (e.g., is not equal to) the additional checksum value. The first network device may thereby determine that the second network device has not determined the additional CAK and may refrain from performing any additional processing steps described herein.

As shown by reference number <NUM>, the first network device and the second network device may communicate to cause the MACsec session to utilize the additional CAK. For example, the first network device, based on validating the checksum value and/or determining that the second network device has determined the additional CAK, may initiate a handshake procedure between the first network device and the second network device, in which the network devices exchange information (e.g., based on the additional CAK) to update the MACsec session to utilize the additional CAK. In some implementations, when updating the MACsec session to utilize the additional CAK, the first network device and the second network device may update the name of the MACsec session. For example, the first network device and the second network device may each determine, based on the additional CAK, an updated name (e.g., a new CAK name or a new CKN) of the MACsec session and may communicate messages (e.g., hello messages or keep-alive messages) to each other that include the updated name. In some implementations, the first network device may determine the updated name in association with determining the additional CAK (e.g., as described herein in relation to <FIG> and reference number <NUM>) and/or the second network device may determine the updated name in association with determining the additional CAK (e.g., as described herein in relation to <FIG> and reference number <NUM>).

<FIG> is a diagram of an example environment <NUM> in which systems and/or methods described herein may be implemented. As shown in <FIG>, environment <NUM> may include two network devices <NUM> (shown as network device <NUM>-<NUM> and network device <NUM>-<NUM>) and a network <NUM>. Devices of environment <NUM> may interconnect via wired connections, wireless connections, or a combination of wired and wireless connections.

Network device <NUM> includes one or more devices capable of receiving, processing, storing, routing, and/or providing traffic (e.g., a packet or other information or metadata) in a manner described herein. For example, network device <NUM> may include a router, such as a label switching router (LSR), a label edge router (LER), an ingress router, an egress router, a provider router (e.g., a provider edge router or a provider core router), a virtual router, or another type of router. Additionally, or alternatively, network device <NUM> may include a gateway, a switch, a firewall, a hub, a bridge, a reverse proxy, a server (e.g., a proxy server, a cloud server, or a data center server), a load balancer, and/or a similar device. In some implementations, network device <NUM> may be a physical device implemented within a housing, such as a chassis. In some implementations, network device <NUM> may be a virtual device implemented by one or more computer devices of a cloud computing environment or a data center. In some implementations, a group of network devices <NUM> may be a group of data center nodes that are used to route traffic flow through network <NUM>. In some implementations, two network devices <NUM> (e.g., network device <NUM>-<NUM> and network device <NUM>-<NUM>) may communicate via a MACsec session, as described elsewhere herein.

Network <NUM> includes one or more wired and/or wireless networks. For example, network <NUM> may include a packet switched network, a cellular network (e.g., a fifth generation (<NUM>) network, a fourth generation (<NUM>) network, such as a long-term evolution (LTE) network, a third generation (<NUM>) network, a code division multiple access (CDMA) network, a public land mobile network (PLMN), a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), a telephone network (e.g., the Public Switched Telephone Network (PSTN)), a private network, an ad hoc network, an intranet, the Internet, a fiber optic-based network, a cloud computing network, or the like, and/or a combination of these or other types of networks.

<FIG> is a diagram of example components of a device <NUM>, which may correspond to network device <NUM>. In some implementations, network device <NUM> includes one or more devices <NUM> and/or one or more components of device <NUM>. As shown in <FIG>, device <NUM> may include a bus <NUM>, a processor <NUM>, a memory <NUM>, an input component <NUM>, an output component <NUM>, and a communication component <NUM>.

Bus <NUM> includes one or more components that enable wired and/or wireless communication among the components of device <NUM>. Bus <NUM> may couple together two or more components of <FIG>, such as via operative coupling, communicative coupling, electronic coupling, and/or electric coupling. Processor <NUM> includes a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, and/or another type of processing component. Processor <NUM> is implemented in hardware, firmware, or a combination of hardware and software. In some implementations, processor <NUM> includes one or more processors capable of being programmed to perform one or more operations or processes described elsewhere herein.

Memory <NUM> includes volatile and/or nonvolatile memory. For example, memory <NUM> may include random access memory (RAM), read only memory (ROM), a hard disk drive, and/or another type of memory (e.g., a flash memory, a magnetic memory, and/or an optical memory). Memory <NUM> may include internal memory (e.g., RAM, ROM, or a hard disk drive) and/or removable memory (e.g., removable via a universal serial bus connection). Memory <NUM> may be a non-transitory computer-readable medium. Memory <NUM> stores information, instructions, and/or software (e.g., one or more software applications) related to the operation of device <NUM>. In some implementations, memory <NUM> includes one or more memories that are coupled to one or more processors (e.g., processor <NUM>), such as via bus <NUM>.

Input component <NUM> enables device <NUM> to receive input, such as user input and/or sensed input. For example, input component <NUM> may include a touch screen, a keyboard, a keypad, a mouse, a button, a microphone, a switch, a sensor, a global positioning system sensor, an accelerometer, a gyroscope, and/or an actuator. Output component <NUM> enables device <NUM> to provide output, such as via a display, a speaker, and/or a light-emitting diode. Communication component <NUM> enables device <NUM> to communicate with other devices via a wired connection and/or a wireless connection. For example, communication component <NUM> may include a receiver, a transmitter, a transceiver, a modem, a network interface card, and/or an antenna.

Device <NUM> may perform one or more operations or processes described herein. For example, a non-transitory computer-readable medium (e.g., memory <NUM>) may store a set of instructions (e.g., one or more instructions or code) for execution by processor <NUM>. Processor <NUM> may execute the set of instructions to perform one or more operations or processes described herein. In some implementations, execution of the set of instructions, by one or more processors <NUM>, causes the one or more processors <NUM> and/or the device <NUM> to perform one or more operations or processes described herein. In some implementations, hardwired circuitry is used instead of or in combination with the instructions to perform one or more operations or processes described herein. Additionally, or alternatively, processor <NUM> may be configured to perform one or more operations or processes described herein.

<FIG> is a diagram of example components of a device <NUM>. Device <NUM> may correspond to network device <NUM>. In some implementations, network device <NUM> may include one or more devices <NUM> and/or one or more components of device <NUM>. As shown in <FIG>, device <NUM> may include one or more input components <NUM>-<NUM> through <NUM>-B (B ≥ <NUM>) (hereinafter referred to collectively as input components <NUM>, and individually as input component <NUM>), a switching component <NUM>, one or more output components <NUM>-<NUM> through <NUM>-C (C ≥ <NUM>) (hereinafter referred to collectively as output components <NUM>, and individually as output component <NUM>), and a controller <NUM>.

Controller <NUM> may perform one or more processes described herein. Controller <NUM> may perform these processes in response to executing software instructions encoded by a computer-readable medium. A computer-readable medium can include a non-transitory memory device. A memory device includes memory space within a single physical storage device or memory space spread across multiple physical storage devices. Additionally, or alternatively, a computer-readable medium can include transient media such as carrier signals and transmission media.

<FIG> is a flowchart of an example process <NUM> associated with automatic generation and update of CAKs for MACsec protocol. In some implementations, one or more process blocks of <FIG> are performed by a first network device (e.g., network device <NUM>-<NUM>). In some implementations, one or more process blocks of <FIG> are performed by another device or a group of devices separate from or including the first network device, such as a second network device (e.g., network device <NUM>-<NUM>). Additionally, or alternatively, one or more process blocks of <FIG> may be performed by one or more components of device <NUM>, such as processor <NUM>, memory <NUM>, input component <NUM>, output component <NUM>, and/or communication component <NUM>; one or more components of device <NUM>, such as input component <NUM>, switching component <NUM>, output component <NUM>, and/or controller <NUM>; and/or one or more other components.

As shown in <FIG>, process <NUM> may include identifying a MACsec session between the first network device and a second network device, wherein the MACsec session utilizes a CAK (block <NUM>). For example, the first network device may identify a MACsec session between the first network device and a second network device, as described above. In some implementations, the MACsec session utilizes a CAK.

As further shown in <FIG>, process <NUM> may include determining, using a KDF and one or more KDF input parameters, an additional CAK (block <NUM>). For example, the first network device may determine, using one or more KDF input parameters, an additional CAK, as described above.

As further shown in <FIG>, process <NUM> may include encrypting at least one of the one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information (block <NUM>). For example, the first network device may encrypt at least one of the one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information, as described above.

As further shown in <FIG>, process <NUM> may include sending, to the second network device, a first message that includes the encrypted KDF input information (block <NUM>). For example, the first network device may send, to the second network device, a first message that includes the encrypted KDF input information, as described above.

As further shown in <FIG>, process <NUM> may include receiving, from the second network device and based on sending the first message, a second message that includes a checksum value (block <NUM>). For example, the first network device may receive, from the second network device and based on sending the first message, a second message that includes a checksum value, as described above.

As further shown in <FIG>, process <NUM> may include determining, based on the checksum value, that the second network device has determined the additional CAK (block <NUM>). For example, the first network device may determine, based on the checksum value, that the second network device has determined the additional CAK, as described above.

As further shown in <FIG>, process <NUM> may include communicating, with the second network device, to cause the MACsec session to utilize the additional CAK (block <NUM>). For example, the first network device may communicate, with the second network device, to cause the MACsec session to utilize the additional CAK, as described above.

In a first implementation, the one or more KDF input parameters include at least one of a KDF parameter, a key parameter, a label parameter, or a context parameter.

In a second implementation, alone or in combination with the first implementation, the encrypted KDF input information is encrypted using a SAK or a KEK, each of which is associated with the MACsec session.

In a third implementation, alone or in combination with one or more of the first and second implementations, the first message is an MKPDU.

In a fourth implementation, alone or in combination with one or more of the first through third implementations, the encrypted KDF input information is included in a CAK name field of the MKPDU.

In a fifth implementation, alone or in combination with one or more of the first through fourth implementations, the second message is an MKPDU.

In a sixth implementation, alone or in combination with one or more of the first through fifth implementations, the checksum value is included in a CAK name field of the MKPDU.

In a seventh implementation, alone or in combination with one or more of the first through sixth implementations, the checksum value is associated with the second network device determining the additional CAK based on the encrypted KDF input information.

In an eighth implementation, alone or in combination with one or more of the first through seventh implementations, the first message includes an indicator indicating that the first message includes the encrypted KDF input information, wherein the second network device is to process the first message to identify the indicator and the encrypted KDF input information; decrypt, based on the indicator, the encrypted KDF input information to determine at least one of the one or more KDF input parameters or the KDF identification information; and determine, based on determining the at least one of the one or more KDF input parameters or the KDF identification information, the additional CAK.

In a ninth implementation, alone or in combination with one or more of the first through eighth implementations, the encrypted KDF input information is encrypted using an encryption key associated with the additional CAK.

In a tenth implementation, alone or in combination with one or more of the first through ninth implementations, the encrypted KDF input information is included in a CAK name field of the first message.

In an eleventh implementation, alone or in combination with one or more of the first through tenth implementations, the first message includes an indicator indicating that the first message includes the encrypted KDF input information.

In a twelfth implementation, alone or in combination with one or more of the first through eleventh implementations, the second message includes a checksum value, wherein the checksum value is associated with the second network device determining the additional CAK based on the encrypted KDF input information.

In a thirteenth implementation, alone or in combination with one or more of the first through twelfth implementations, the second message includes a checksum value and an indicator indicating that the second message includes the checksum value.

In a fourteenth implementation, alone or in combination with one or more of the first through thirteenth implementations, communicating to cause the MACsec session to utilize the additional CAK includes processing the second message to determine a checksum value included in the second message; processing the additional CAK to determine an additional checksum value; validating, based on the additional checksum value, the checksum value; and communicating, with the second network device and based on validating the checksum value, to cause the MACsec session to utilize the additional CAK.

Although <FIG> shows example blocks of process <NUM>, in some implementations, process <NUM> includes additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in <FIG>.

<FIG> is a flowchart of an example process <NUM> associated with automatic generation and update of CAKs for MACsec protocol. In some implementations, one or more process blocks of <FIG> are performed by a second network device (e.g., network device <NUM>-<NUM>). In some implementations, one or more process blocks of <FIG> are performed by another device or a group of devices separate from or including the second network device, such as a first network device (e.g., network device <NUM>-<NUM>). Additionally, or alternatively, one or more process blocks of <FIG> may be performed by one or more components of device <NUM>, such as processor <NUM>, memory <NUM>, input component <NUM>, output component <NUM>, and/or communication component <NUM>; one or more components of device <NUM>, such as input component <NUM>, switching component <NUM>, output component <NUM>, and/or controller <NUM>; and/or one or more other components.

As shown in <FIG>, process <NUM> may include receiving, from a first network device, a first message that includes encrypted KDF input information (block <NUM>). For example, the second network device may receive, from a first network device, a first message that includes encrypted KDF input information, as described above.

As further shown in <FIG>, process <NUM> may include processing the first message to determine the encrypted KDF input information (block <NUM>). For example, the second network device may process the first message to determine the encrypted KDF input information, as described above.

As further shown in <FIG>, process <NUM> may include decrypting the encrypted KDF input information to determine at least one of one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters (block <NUM>). For example, the second network device may decrypt the encrypted KDF input information to determine at least one of one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters, as described above.

As further shown in <FIG>, process <NUM> may include determining, based on determining at least one of the one or more KDF input parameters or the KDF identification information that identifies the KDF and the one or more KDF input parameters, a CAK for a MACsec session between the first network device and the second network device (block <NUM>). For example, the second network device may determine, based on determining at least one of the one or more KDF input parameters or the KDF identification information that identifies the KDF and the one or more KDF input parameters, a CAK for a MACsec session between the first network device and the second network device, as described above.

As further shown in <FIG>, process <NUM> may include determining, based on the CAK, a checksum value (block <NUM>). For example, the second network device may determine, based on the CAK, a checksum value, as described above.

As further shown in <FIG>, process <NUM> may include sending, to the first network device, a second message that includes the checksum value (block <NUM>). For example, the second network device may send, to the first network device, a second message that includes the checksum value, as described above.

In a first implementation, process <NUM> includes communicating, with the first network device and based on sending the second message, to cause the MACsec session to utilize the CAK.

In a second implementation, alone or in combination with the first implementation, at least one of the first message and the second message is an MKPDU.

In a third implementation, alone or in combination with one or more of the first and second implementations, the second message includes an indicator indicating that the second message includes the checksum value.

Thus, from one perspective, there has now been described a first network device which may identify a MACsec session between the first network device and a second network device that utilizes a CAK, may determine, using a KDF and one or more KDF input parameters, an additional CAK, may encrypt the one or more KDF input parameters and/or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information, and may send, to the second network device, a first message that includes the encrypted KDF input information. The first network device may receive, from the second network device, based on sending the first message, a second message that includes a checksum value, may determine, based on the checksum value, that the second network device has determined the additional CAK, and may communicate, with the second network device, to cause the MACsec session to utilize the additional CAK.

As an example, "at least one of: a, b, or c" is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiple of the same item.

Claim 1:
A method (<NUM>), comprising:
identifying (<NUM>), by a first network device, a Media Access Control Security, MACsec, session between the first network device and a second network device,
wherein the MACsec session utilizes a connectivity association key, CAK;
determining (<NUM>), by the first network device and using a key derivation function, KDF, and one or more KDF input parameters, an additional CAK;
encrypting (<NUM>), by the first network device, at least one of the one or more KDF input parameters or KDF identification information that identifies the KDF and the one or more KDF input parameters to generate encrypted KDF input information;
sending (<NUM>), by the first network device and to the second network device, a first message that includes the encrypted KDF input information;
receiving (<NUM>), by the first network device, from the second network device, and based on sending the first message, a second message that includes a checksum value;
determining (<NUM>), by the first network device and based on the checksum value, that the second network device has determined the additional CAK; and
communicating (<NUM>), by the first network device and with the second network device, to cause the MACsec session to utilize the additional CAK.