Congestion controller for ethernet switch

• US 20040081090A1
• Filed: 08/28/2003
• Published: 04/29/2004
• Est. Priority Date: 09/09/2002
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Hara, Toshihide, Maeda, Takahide
• Granted Patent: US 7,525,911 B2
• Time in Patent Office: Days
• US Class Current: 370/229
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/13 in a LAN segment, e.g. ring or bus
• CPC Class Codes: H04L 47/22 Traffic shaping
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/266 Stopping or restarting the source, e.g. X-on or X-off
• CPC Class Codes: H04L 47/29 using a combination of thresholds
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/50 Queue scheduling

Abstract

The present invention relates to a congestion controller, which suppress transmission traffic based on a traffic attribute in the event of congestion especially in a circumstance in which a plurality of Ethernet switches are connected. The congestion controller in the Ethernet switch comprises a plurality of transmission queues having different priority each other, a receiving unit for receiving a PAUSE frame, and a restriction unit to restrict transmission traffic from the transmission queue by the received PAUSE frame, wherein the restriction unit restricts the transmission traffic from a transmission queue of lowest priority by a PAUSE frame received at a time other than a PAUSE time and suppresses transmission traffic from a transmission queue of highest priority by a PAUSE frame received during the PAUSE time.

Claims

1. A congestion controller for an Ethernet switch comprising

a plurality of transmission queues which have different priorities,

a receiving means for receiving a PAUSE frame,

a restriction means for restricting transmission traffic from the transmission queues by the received PAUSE frame, wherein

the restriction means restricts the transmission traffic from a transmission queue of the lowest priority by the PAUSE frame received at a time other than the PAUSE time, and restricts the transmission traffic from the transmission queue of the higher priority, by the PAUSE frame received during the PAUSE time.

2. A congestion controller for an Ethernet switch comprising

a transmission queue,

a receiving means for receiving a PAUSE frame,

a shaping means for shaping the transmission traffic from the transmission queue by the received PAUSE frame, wherein

the shaping means restricts transmission speed of the transmission traffic from the transmission queue to or below a transmission speed based on a predetermined shaping value.

3. A congestion controller according to claim 2 in which the restriction of the transmission speed is performed by providing a gap in the transmission traffic.

4. A congestion controller for an Ethernet switch comprising

a transmission queue,

an identifying means for identifying an input port which causes congestion by counting packets resident in the transmission queue, corresponding to the input port, and

a transmission means for transmitting a PAUSE frame to other switch which is connected to the identified input port.

5. A congestion controller according to claim 4 in which

the identifying means further identifies an application of the identified input port based on the attributes of the packets, and

the transmission means notifies the other switch of the identified application by a PAUSE frame transmitted thereto.