Network apparatus, edge router, and packet communication system

A packet communication system, comprising:

• a first communication apparatus to be coupled to a first link that is used in time division of a first kind of time slots;
• a second communication apparatus to be coupled to a second link that is used in time division of a second kind of time slots, each of the second kind of time slots is shorter than each of the first kind of time slots;
• and
• a network apparatus relaying packets communicated between the first and second communication apparatuses, the network apparatus comprises:
• a first port unit to be coupled to the first link;
• a second port unit to be coupled to the second link;
• at least two output banks that are storage areas to temporarily store
• the packets flowing from the first link to the second link;
• a switch coupling between the first port unit and the second port unit;
• and
• a controller to control the switch;
• and
• upon detecting switching to a first transmission time slot among the first kind of time slots, the controller couples the first port unit through the switch to a first output bank of the output banks and couples another output bank to the second port unit or the second link to cause the first output bank to temporarily store packets from the first link,
• upon detecting switching from the first transmission time slot to a next time slot of the first kind of time slots, the controller couples the first output bank to the second port unit or the second link and couples the first port unit through the switch to the another output bank, and
• upon detecting switching to a second transmission time slot among the second kind of time slots, the controller causes the second port unit to transmit the packets stored in the output bank coupled to the second port unit or the second link to the second link.

A non-transitory storage medium storing a program for causing a network apparatus to execute a procedure,

• the procedure comprising:
• upon detecting switching to a first transmission time slot among a first kind of time slots, coupling a first port unit to be coupled to a first link that is used in time division of the first kind of time slots through a switch to a first output bank of at least two output banks, and coupling another output bank to a second port unit to be coupled to a second link that is used in time division of a second kind of time slots or the second link, the network apparatus comprises the first port unit, the second port unit, the switch and the at least two output banks that are storage areas to temporarily store packets flowing from the first link to the second link, and each of the second kind of time slots is shorter than each of the first kind of time slots;
• causing the first output bank to temporarily store packets from the first link;
• upon detecting switching from the first transmission time slot to a next time slot among the first kind of time slots, coupling the first output bank to the second port unit or the second link and coupling the first port unit through the switch to the another output bank, and
• upon detecting switching to a second transmission time slot among the second kind of time slots, causing the second port unit to transmit the packets stored in the output bank coupled to the second port unit or the second link to the second link.