Synchronizing resource bindings within computer network

An intermediate network device positioned between a client device and a server in a network, the intermediate network device comprising:

• at least one interface card that receives an allocation message from the server that allocates a layer three (L3) network address for use by the client device identified by a unique identifier;
• a control unit that stores data defining a binding between the unique identifier identifying the client device and the L3 network address reserved for use by the client device,
• wherein the control unit includes a binding synchronization module that determines whether to release the binding between the unique identifier identifying the client device and the L3 network address reserved for use by the client device based on whether a communication has been received from a remote authentication dial-in user server (RADIUS) server specifying a RADIUS-initiated disconnect for the client device, determines, upon determining that the communication has been received from the RADIUS server specifying the RADIUS-initiated disconnect for the client device, that the binding release did not occur in response to receiving a release message from the client device, automatically generates a release message on behalf of the client device in response to determining that the binding release did not occur in response to receiving a release message from the client device, and outputs the automatically generated release message to the server that reserved the L3 network address for use by the client device identified by the unique identifier.

A network system comprising:

• a remote dial in user service (RADIUS) server;
• a dynamic host configuration protocol (DHCP) client;
• a DHCP server that allocates L3 network addresses for use by DHCP clients;
• at least one DHCP relay device positioned between the DHCP client device and the DHCP server, the at least one DHCP relay device comprising:
• at least one interface card that receives a DHCP message from the DHCP server allocating a layer three (L3) network address for use by the DHCP client device identified by a unique identifier;
• a control unit that stores data defining a binding between the unique identifier identifying the DHCP client device and the L3 network address reserved for use by the DHCP client device,
• wherein the control unit includes a binding synchronization module that determines whether to release the binding between the unique identifier identifying the DHCP client device and the L3 network address reserved for use by the DHCP client device based on whether a communication has been received from the RADIUS server specifying a RADIUS-initiated disconnect for the DHCP client device, determines, upon determining that the communication has been received from the RADIUS server specifying the RADIUS-initiated disconnect for the DHCP client device, that the binding release did not occur in response to receiving a DHCP release message from the DHCP client device, automatically generates a DHCP release message on behalf of the client device in response to determining that the binding release did not occur in response to receiving a DHCP release message from the DHCP client device, and outputs the automatically generated DHCP release message to the DHCP server that reserved the L3 network address for use by the DHCP client device identified by the unique identifier.

A non-transitory computer-readable storage medium comprising instructions that cause a processor to:

• receive, with an intermediate network device positioned between a client device and a server in a network, an allocation message from the server that allocates a layer three (L3) network address for use by the client device identified by a unique identifier;
• store, with the intermediate network device, data defining a binding between the unique identifier identifying the client device and the L3 network address reserved for use by the client device;
• determine, with the intermediate network device, whether to release the binding between the unique identifier identifying the client device and the L3 network address reserved for use by the client device based on whether a communication has been received from a remote authentication dial-in user server (RADIUS) server specifying a RADIUS-initiated disconnect for the client device;
• upon determining that the communication has been received from the RADIUS server specifying the RADIUS-initiated disconnect for the client device, determine, with the intermediate network device, that the binding release did not occur in response to receiving a release message from the client device;
• automatically generate, with the intermediate network device, a release message on behalf of the client device upon determining that the binding release did not occur in response to receiving a release message from the client device;
• and
• output, with the intermediate network device, the automatically generated release message to the server that reserved the L3 network address for use by the client device identified by the unique identifier.