Reliable Link Layer Packet Retry

An apparatus comprising a first port adapted to communicate over a computer network with a point-to-point link connection to a second port, the first port configured to:

• store a first data packet to be transmitted to the second port,
• transmit to the second port from the buffer a first reliable link layer (RLL) packet over the link, the first RLL packet comprising a first RLL header and the first data packet, the first RLL header preceding the first data packet, the first RLL header comprising an RLL start-of-frame (SOF) character and an RLL packet sequence number (PSN),
• if the first port receives an RLL acknowledgment control packet from the link, acknowledge receipt of the first data packet, the first port does not retain the first data packet in the buffer, and
• if the first port does not receive the RLL acknowledgment packet from the link, acknowledge receipt of the first data packet, the first port does not re-transmit from the buffer the first data packet.

A computer program product for communicating over a network, comprising a computer useable medium having a computer readable program, wherein the computer readable program when executed on a computer causes the computer to:

• store in a buffer of a first port, a first data packet to be transmitted;
• transmit from the buffer of the first port a first reliable link layer (RLL) packet over the link, the first RLL packet comprising a first RLL header and the first data packet, the first RLL header preceding the first data packet, the first RLL header comprising an RLL start-of-frame (SOF) character and an RLL packet sequence number (PSN);
• if the first port receives an RLL acknowledgment control packet from the link, acknowledge receipt of the first data packet, the first port to not retain the first data packet in the buffer;
• and
• if the first port does not receive the RLL acknowledgment packet from the link, acknowledge receipt of the first data packet, re-transmit from the buffer the first data packet.