JP2008271611A5

JP2008271611A5 -

Info

Publication number: JP2008271611A5
Application number: JP2008207691A
Authority: JP
Filing date: 2008-08-12
Publication date: 2010-07-01
Anticipated expiration: 2025-05-26

Claims

In a packet transfer method in which a packet transfer device transfers data,
The packet transfer apparatus includes an interface unit that transmits and receives packets, a switch that outputs a received packet to a destination interface unit, and a shaping unit that controls transmission timing of the packet,
The shaping unit includes a packet buffer for temporarily storing the received packet;
The packet transfer method includes:
A bandwidth control step in which the shaping unit controls a transmission bandwidth of the packet;
A request selecting step in which the shaping unit determines a packet to be read from the packet buffer;
The bandwidth control step includes:
A first timing generation step in which the shaping unit determines whether reading of the received packet from the packet buffer using a token bucket algorithm is equal to or lower than a minimum guaranteed bandwidth;
A second timing generation step in which the shaping unit determines whether reading of the received packet from the packet buffer using a leaky bucket algorithm is less than or equal to a maximum allowable bandwidth;
The token bucket algorithm determines that reading of the packet from the packet buffer is below the minimum guaranteed bandwidth when the token amount held in the token bucket is positive, and the leaky bucket algorithm is held in the leaky bucket When the token amount is 0, it is determined that reading of the packet from the packet buffer is below the maximum allowable bandwidth,
In the request selection step, it is determined in the first timing generation step that reading of the packet from the packet buffer exceeds a minimum guaranteed bandwidth, and in the second timing generation step, reading of the packet from the packet buffer is performed. A packet transfer method, comprising: determining that the packet can be read from the packet buffer when it is determined that the bandwidth is equal to or less than a maximum allowable bandwidth.

In the request selection step, in the first timing generation step, it is determined that reading of the packet from the packet buffer is not more than a minimum guaranteed bandwidth, and in the second timing generation step, the reading of the packet from the packet buffer is maximum. The packet transfer method according to claim 1, further comprising: a step of determining that the packet can be read from the packet buffer when the shaping unit determines that the allowable bandwidth is exceeded.

The packet transfer apparatus includes a control unit that controls the shaping unit,
In the packet transfer method, the reading of the packet from the packet buffer in the first timing generation step is determined to be less than a minimum guaranteed bandwidth, and the reading of the packet from the packet buffer in the second timing generation step The control unit includes a step of changing a setting of a mode for determining that the packet is readable or impossible from the packet buffer in the request selection step when it is determined that the maximum allowable bandwidth is exceeded. The packet transfer method according to claim 1.

4. The first timing generation step according to claim 1, wherein, in the token bucket algorithm, a token amount held in the token bucket is allowed to take a negative value. 5. Packet transfer method.

2. The request selection step includes a step of determining the packet read from the packet buffer based on signals output in the first timing generation step and the second timing generation step. 4. The packet transfer method according to any one of items 1 to 3.

4. The packet transfer method according to claim 3, further comprising a step in which the control unit switches between valid and invalid of timing generation by the first timing generation step and the second timing generation step. 5.

In the request selection step, it is determined in the first timing generation step that the reading of the packet from the packet buffer exceeds a minimum guaranteed bandwidth, and in the second timing generation step, the reading of the packet from the packet buffer is performed 4. The packet transfer according to claim 1, wherein when it is determined that the maximum allowable bandwidth is exceeded, the shaping unit determines that the packet cannot be read from the packet buffer. 5. Method.

In the request selection step, in the first timing generation step, it is determined that reading of the packet from the packet buffer is not more than a minimum guaranteed bandwidth, and in the second timing generation step, the reading of the packet from the packet buffer is maximum. 4. The packet transfer method according to claim 1, wherein when it is determined that the bandwidth is equal to or less than an allowable bandwidth, the shaping unit determines that the packet can be read from the packet buffer. 5.

The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received packet on a best effort basis. Or a packet transfer method according to any one of the above.

The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received packet at a best effort,
7. The packet transfer method according to claim 3, wherein the control unit further sets validity or invalidity of timing generation by each timing generation unit. 8.

5. The method according to claim 1, wherein the packet transfer method further includes a step in which the shaping unit sets a maximum value to a token amount held in the token bucket in the first timing generation step. Or a packet transfer method according to any one of the above.

  The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received packet at a best effort,
  The shaping unit includes a valid / invalid holding unit that holds validity or invalidity of timing generation by each timing generation step,
  7. The packet transfer method according to claim 3, further comprising a step in which the control unit sets the validity / invalidity of timing generation in each timing generation step in the validity / invalidity holding unit. The packet transfer method described.

The packet transfer method according to claim 1, wherein the interface unit includes an optical / electrical conversion unit that converts a received optical signal into an electrical signal.

  In the packet transfer method between the station-side optical termination device and the subscriber-side optical termination device in a network system in which the station-side optical termination device and the subscriber-side optical termination device are connected by an optical fiber network,
  The station side optical termination device is connected to a core network,
  The station-side optical termination device includes an interface unit that transmits and receives a fixed-length frame in which a variable-length packet is stored, a switch that outputs to a destination interface unit of the received variable-length packet, and a shaping that controls transmission timing of the variable-length packet Part
  The shaping unit includes a packet buffer that temporarily stores the received variable-length packet;
  The packet transfer method includes:
  A bandwidth control step in which the shaping unit controls a transmission bandwidth of the variable-length packet;
  A request selecting step in which the shaping unit determines the variable length packet read from the packet buffer;
  The bandwidth control step includes:
  A first timing generation step in which the shaping unit determines whether reading of the received packet from the packet buffer using a token bucket algorithm is below a minimum guaranteed bandwidth;
  A second timing generation step in which the shaping unit determines whether reading of the received packet from the packet buffer using a leaky bucket algorithm is less than or equal to a maximum allowable bandwidth;
  The token bucket algorithm determines that the reading of the variable length packet from the packet buffer is less than the minimum guaranteed bandwidth when the token amount held in the token bucket is positive, and the leaky bucket algorithm holds in the leaky bucket When the amount of tokens to be performed is 0, the reading of the variable length packet from the packet buffer is determined to be less than the maximum allowable bandwidth,
  In the request selection step, it is determined that the reading of the variable length packet from the packet buffer in the first timing generation step exceeds a minimum guaranteed bandwidth, and the variable length from the packet buffer is determined in the second timing generation unit. A packet transfer method comprising: a step of determining that the variable-length packet can be read from the packet buffer when the packet reading is determined to be less than or equal to a maximum allowable bandwidth.

In the request selection step, it is determined in the first timing generation step that the reading of the variable length packet from the packet buffer is not more than a minimum guaranteed bandwidth, and in the second timing generation step, the variable length packet from the packet buffer is determined. 15. The method of claim 14, further comprising: determining that the variable-length packet can be read from the packet buffer when it is determined that the reading of the packet exceeds a maximum allowable bandwidth. Packet transfer method.

The station side optical termination device includes a control unit that controls the shaping unit,
In the packet transfer method, it is further determined that reading of the variable length packet from the packet buffer in the first timing generation step is less than a minimum guaranteed bandwidth, and the variable from the packet buffer in the second timing generation step. When it is determined that the long packet read exceeds the maximum allowable bandwidth, the control unit sets the mode so that the request selection step determines that the variable length packet can be read from the packet buffer. The packet transfer method according to claim 14, further comprising a changing step.

17. The method according to claim 14, wherein, in the first timing generation step, in the token bucket algorithm, a token amount held in the token bucket is allowed to take a negative value. Packet transfer method.

The request selection step includes a step of determining the variable-length packet read from the packet buffer based on signals output from the first timing generation step and the second timing generation step. Item 17. The packet transfer method according to any one of Items 14 to 16.

17. The packet transfer method according to claim 16, further comprising a step in which the control unit switches between valid and invalid timing generation by the first timing generation step and the second timing generation step.

In the request selection step, it is determined in the first timing generation step that the reading of the variable length packet from the packet buffer exceeds a minimum guaranteed bandwidth, and in the second timing generation step, the variable from the packet buffer is determined. 17. The method according to claim 14, wherein the shaping unit determines that the variable-length packet can be read from the packet buffer when it is determined that reading of the long packet exceeds a maximum allowable bandwidth. The packet transfer method according to one.

In the request selection step, the first timing generation unit determines that reading of the variable length packet from the packet buffer is less than or equal to a minimum guaranteed bandwidth, and the second timing generation unit determines the variable length from the packet buffer. 17. The method according to claim 14, wherein the shaping unit determines that the variable-length packet can be read from the packet buffer when it is determined that the packet reading is equal to or less than a maximum allowable bandwidth. The packet transfer method described.

17. The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received variable-length packet at a best effort. The packet transfer method according to any one of the above.

The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received variable length packet at best effort,
20. The packet transfer method according to claim 16 or 19, wherein the control unit further sets validity or invalidity of timing generation by each timing generation step.

17. The method according to claim 14, wherein the packet transfer method further includes a step in which the shaping unit sets a maximum value to a token amount held in the token bucket in the first timing generation step. Or a packet transfer method according to any one of the above.

  The bandwidth control step includes a third timing generation step in which the shaping unit outputs a transmission timing of the packet for transmitting the received variable length packet at best effort,
  The shaping unit includes a valid / invalid holding unit that holds validity or invalidity of timing generation by each timing generation step,
  The packet transfer method further includes a step in which the control unit sets the validity / invalidity of timing generation in each timing generation step in the validity / invalidity holding unit. The packet transfer method described.

The packet transfer method according to any one of claims 14 to 16, wherein the interface unit includes an optical / electrical conversion unit that converts a received optical signal into an electrical signal.