Method for managing network connections

A method for managing network connections connected through a network device, the network device storing a connection-tracking (Conntrack) table where entries of tracked connection data related respectively to the network connections are stored, the method comprising steps of:

• in response to receipt of a request for establishing a new network connection, storing in the Conntrack table an entry of tracked connection data that is related to the new network connection to be established, and updating a current tracked-connection count by adding one thereto, the current tracked-connection count representing a number of entries of tracked connection data that are currently stored in the Conntrack table and that are related respectively to existing network connections connected through the network device;
• determining a priority level of the new network connection according to a data packet transmitted through the new network connection;
• determining whether to output data packets that are received through the new network connection based at least on the current tracked-connection count and the priority level of the new network connection;
• and
• determining not to output the data packets and removing from the Conntrack table the entry of tracked connection data related to the new network connection when a connection condition is satisfied, wherein the connection condition is that the current tracked-connection count is smaller than a maximum number of data entries which can be stored in the Conntrack table and greater than a first predetermined count threshold which is smaller than the maximum number of data entries, and that the priority level of the new network connection is a predetermined priority level that is lower than a highest priority level,
• wherein the step of determining a priority level of the new network connection includes determining whether the priority level of the new network connection is the highest priority level, a lowest priority level, or a medium priority level that is between the highest priority level and the lowest priority level,
• wherein the predetermined priority level is the lowest priority level;
• and
• wherein the method further comprises:
• under the connection condition, when it is determined that the priority level of the new network connection is the medium priority level, which is the predetermined priority level, and the current tracked-connection count is greater than a second predetermined count threshold which is smaller than the maximum number of data entries and greater than the first predetermined count threshold, determining not to output the data packets and removing from the Conntrack table the entry of tracked connection data related to the new network connection.

A method for managing network connections connected through a network device, the network device storing a connection-tracking (Conntrack) table where entries of tracked connection data related respectively to the network connections are stored, the method comprising steps of:

• in response to receipt of a request for establishing a new network connection, storing in the Conntrack table an entry of tracked connection data that is related to the new network connection to be established, and updating a current tracked-connection count by adding one thereto, the current tracked-connection count representing a number of entries of tracked connection data that are currently stored in the Conntrack table and that are related respectively to existing network connections connected through the network device;
• determining a priority level of the new network connection according to a data packet transmitted through the new network connection;
• and
• determining whether to output data packets that are received through the new network connection based at least on the current tracked-connection count and the priority level of the new network connection,
• wherein the step of determining a priority level of the new network connection includes determining whether the priority level of the new network connection is one of a number N of priority levels, where a first one of the number N of priority levels is a highest priority level, an Nth one of the number N of priority levels is a lowest priority level, a jth one of the number N of priority levels is higher than a (j+1)th one of the number N of priority levels, and j is an integer ranging from one to (N−1),
• wherein the method further comprises
• when it is determined that the priority level of the new network connection is the Nth one of the number N of priority levels and the current tracked-connection count is greater than an Nth one of a number N of predetermined count thresholds, determining to output the data packets and removing from the Conntrack table one of the entries of tracked connection data that is related to one of the existing network connections which has the Nth one of the number N of priority levels, where the number N of predetermined count thresholds are all smaller than a maximum number of data entries which can be stored in the Conntrack table, an ith one of the number N of predetermined count thresholds is greater than an (i+1)th one of the number N of predetermined count thresholds, and i is an integer ranging from one to (N−1).

A method for managing network connections connected through a network device, the network device storing a connection-tracking (Conntrack) table where entries of tracked connection data related respectively to the network connections are stored, the method comprising steps of:

• in response to receipt of a request for establishing a new network connection, storing in the Conntrack table an entry of tracked connection data that is related to the new network connection to be established, and updating a current tracked-connection count by adding one thereto, the current tracked-connection count representing a number of entries of tracked connection data that are currently stored in the Conntrack table and that are related respectively to existing network connections connected through the network device;
• determining a priority level of the new network connection according to a data packet transmitted through the new network connection;
• and
• determining whether to output data packets that are received through the new network connection based at least on the current tracked-connection count and the priority level of the new network connection,
• wherein the step of determining a priority level of the new network connection includes determining whether the priority level of the new network connection is one of a number N of priority levels, where a first one of the number N of priority levels is a highest priority level, an Nth one of the number N of priority levels is a lowest priority level, a jth one of the number N of priority levels is higher than a (j+1)th one of the number N of priority levels, and j is an integer ranging from one to (N−1),
• wherein the method further comprises
• when it is determined that the priority level of the new network connection is the Nth one of the number N of priority levels and the current tracked-connection count is greater than an Nth one of a number N of predetermined count thresholds, determining not to output the data packets and removing from the Conntrack table the entry of tracked connection data related to the new network connection, where the number N of predetermined count thresholds are all smaller than a maximum number of data entries which can be stored in the Conntrack table, an ith one of the number N of predetermined count thresholds is greater than an (i+1)th one of the number N of predetermined count thresholds, and i is an integer ranging from one to (N−1).