Method for transmitting packets in a network
Stream Control Transmission Protocol (SCTP) transmits packets to the remote peer with a size equal or smaller than Maximum Transmission Unit (MTU). The MTU can be discovered by SCTP utilizing the path-MTU discovery algorithm of RFC1191 (or similar techniques). However the MTU of a certain path within a SCTP association can change over time. If the path MTU grows then there is no problem. If the path MTU decreases, then packets with size equal to the old path MTU will not be able to be delivered to the remote peer as the link or router with the smaller MTU will drop the packet. Thus all such packets will remain unacknowledged and will lead to head of line blocking for in-sequence delivery of packets of the streams to which to non-delivered packets belong. This leads to the failure of the association. The proposed method resegments SCTP-packets due to a path MTU decrease in a SCTP association.
1. A method for transmitting packets in a network, comprising:
transmitting packets of a message of a connection, the packets being segmented from a data stream to have a packet size equal to or smaller than a maximum packet size;
assigning each packet of a transmission sequence number;
transmitting the segmented packets to a remote peer of the connection;
continuously monitoring a current maximum packet size;
resegmenting the packets with new transmission sequence numbers when a decrease in the maximum packet size has been monitored, the packets being resegemented to have packet sizes that match the current maximum packet size;
sending a resegment parameter to the remote peer to indicate which previously received transmission sequence numbers are being replaced with a new transmission sequence number; and
transmitting the resegmented packets to the remote user after sending the resegment parameter.
2. The method of claim 1 , wherein
packets are transmitted on a plurality of paths, and
the current maximum packet size is discovered for each path.
3. The method according claim 2 , comprising further:
not transmitting packets having a packet size larger than the maximum packet size.
4. The method according claim 2 , the wherein:
packets are transmitted according to a Stream Control Transmission Protocol (SCTP).
5. The method according claim 1 , comprising further:
not transmitting packets having a packet size larger than the maximum packet size.
6. The method according claim 1 , wherein:
packets are transmitted according to a Stream Control Transmission Protocol (SCTP).