Packet transfer device, packet transfer method, and packet transfer program
AssigneeNippon Telegraph and Telephone Corporation
InventorsMasayuki Nishiki, Masato Nishiguchi, Yuki Takei
Life of this patent
Estimating the term…
Abstract
A packet transfer apparatus registers time information from a system clock on a CPU region to a time information holding table on a hardware region, adds a receiving time to a received packet using a counter value on a hardware clock and the time information registered in the table, and transfers, to a transfer destination, the packet to which the receiving time has been added.
Claims6
A packet transfer apparatus comprising one or more processors configured to:
- obtain time information from a system clock on a CPU region at a predetermined time interval;
- periodically register the obtained time information into a table and a hardware clock on a hardware region,
- wherein periodically registering the obtained time information into the table and the hardware clock comprises:
- updating the table and the hardware clock at the same time for the first time, and periodically updating only the table after the first time;
- receive a packet;
- determine a receiving time using i) the time information periodically updated in the table in the hardware region and ii) a counter value of the hardware clock on the hardware region that indicates an elapsed time;
- add the receiving time to the received packet;
- and
- transfer, to a transfer destination, the packet to which the receiving time has been added.
A packet transfer method that is executed by a packet transfer apparatus, the method comprising:
- obtaining time information from a system clock on a CPU region at a predetermined time interval;
- periodically registering the obtained time information into a table and a hardware clock on a hardware region,
- wherein periodically registering the obtained time information into the table and the hardware clock comprises:
- updating the table and the hardware clock at the same time for the first time, and periodically updating only the table after the first time;
- receiving a packet;
- determining a receiving time using i) the time information periodically registered in the table on the hardware region and ii) a counter value of a hardware clock on the hardware region that indicates an elapsed time;
- adding the receiving time to the received packet;
- and
- transferring, to a transfer destination, the packet to which the receiving time has been added.
A non-transitory computer readable medium storing one or more instructions for causing a computer to execute:
- obtaining time information from a system clock on a CPU region at a predetermined time interval;
- periodically registering the obtained time information into a table and a hardware clock on a hardware region,
- wherein periodically registering the obtained time information into the table and the hardware clock comprises:
- updating the table and the hardware clock at the same time for the first time, and periodically updating only the table after the first time;
- receiving a packet;
- determining a receiving time using i) the time information periodically registered in the table on the hardware region and ii) a counter value of a hardware clock on the hardware region that indicates an elapsed time;
- adding the receiving time to the received packet;
- and
- transferring, to a transfer destination, the packet to which the receiving time has been added.
Dependencies are inferred from the claim text.