Method and device in telecommunications system
AssigneeTelefonaktiebolaget LM Ericsson
InventorsClarence Fransson, Gunnar Larsson, Raimo Sissonen, Bengt Kvist
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Abstract
A method and a buffer structure ensure a fair share of the bandwidth between point-to-point and point-to-multipoint connections with the same or different priorities. For each priority class, the buffer structure includes one queue for each physical link of restoring point-to-point cells for each priority level and one queue for point-to-multipoint cells. When a cell is to be transmitted on a link, the point-to-point and point-to-multipoint cells for this link, if any, from the highest priority class in each case are identified. If the cells belong to the same priority class, the cell stored first is transmitted.
Claims6
Method for achieving fair share between point-to-point connections and point to-multipoint connections in a switch, comprising at least one buffer for each physical link and at least one buffer for point-to-multipoint connections, the method comprising the steps of:
- storing the cells belonging to point-to-point connections in a queue structure according to the physical link on which they are transmitted;
- storing the cells belonging to point-to-multipoint connections in another queue for point-to-multipoint connections;
- selecting a physical link on which a point-to-point cell should be transmitted;
- determining if the first cell in the point-to-multipoint queue should be transmitted on the physical link selected;
- if both a point-to-point cell and a point-to-multipoint cell should be transmitted on the physical link selected, determining which one of the point-to-point cell and the point-to-multipoint cell was first stored in the queue structure and transmitting this cell to an output queue.
A method for achieving fair share between point-to-point connections and point to-multipoint connections in a switch, comprising at least one buffer for each physical link and at least one buffer for point-to-multipoint connections, the method comprising the steps of:
- storing the cells belonging to point-to-point connections in a queue structure according to the physical link on which they are transmitted;
- storing the cells belonging to point-to-multipoint connections in another queue for point-to-multipoint connections;
- selecting a physical link on which a point-to-point cell should be transmitted;
- determining if the first cell in the point-to-multipoint queue should be transmitted on the physical link selected;
- if both a point-to-point cell and a point-to-multipoint cell should be transmitted on the physical link selected, determining which one of the point-to-point cell and the point-to-multipoint cell was first stored in the queue structure and transmitting this cell to an output queue, wherein the first stored cell is determined by:
- adding a sequence number to the cell, depending on the cell's priority class and physical link, before the cell is stored in the buffer;
- for any two cells that should be compared, calculating the difference between their sequence numbers;
- if the absolute value of the difference between the sequence numbers is smaller than the size of the buffers, then transmitting the cell with the lowest sequence number;
- and
- if the absolute value of the difference between the sequence numbers is greater than the size of the buffers, then transmitting the cell with the highest sequence number.
A switch comprising a number of inlet ports, a number of outlet ports, a switch core to which the outlet and inlet ports are connected, a queue structure including at least one queue for point-to-point connections on each physical link and at least one queue for point-to-multipoint connections, a selector which stores each incoming cell in the appropriate queue, a link selector, means for determining if the first cell in a multislot queue should be transmitted on a selected link, an output queue selector adapted to select a cell to transmit according to the cell's physical link and the time when the cell was stored, so that for each link, the cell that was stored first is transmitted first.
A switch comprising:
- a number of inlet ports;
- a number of outlet ports;
- a switch core to which the outlet and inlet ports are connected;
- a queue structure including at least one queue for point-to-point connections on each physical link and at least one queue for point-to-multipoint connections;
- a selector which stores each incoming cell in the appropriate queue;
- a link selector:
- means for determining if the first cell in a multislot queue should be transmitted on a selected link;
- an output queue selector adapted to select a cell to transmit according to the cell's physical link and the time when the cell was stored, so that for each link, the cell that was stored first is transmitted first;
- two or more queue structures to allow cells with different priority classes to be stored in different queue structures;
- and
- a priority class selector to select a priority class to be searched for a cell to be transmitted to the output queue, wherein a logical weight is assigned to each link, and each link is selected for transmission of a cell at a rate depending on the logical weight of the link.
Dependencies are inferred from the claim text.