Downstream frame transfer device, transfer method and transfer program

Patent metadata

Field	Value
Publication number	US-11637647-B2
Application number	US-201917622025-A
Country	US
Kind code	B2
Filing date	Jun 25, 2019
Priority date	Jun 25, 2019
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A transfer device includes: a frame information acquisition unit configured to monitor downstream frames between host devices and OLTs and calculate a statistical value of the downstream frames per a fixed cycle; a frame storage unit configured to store the downstream frames in a plurality of queues; a frame sorting unit configured to input the downstream frames to the queues; and a distribution control unit configured to determine the number of frames to be sequentially input to the queues and increase the number of distributed frames of at least one of the host devices input to an OLT, the OLT having a smaller value of a total number of frames input from all the host devices than a maximum number of rounded frames obtained by dividing a value of a total number of frames input until the frames of all the host devices take turns around the plurality of queues by the number of OLTs. As a result, a delay requirement can be satisfied while a memory size of the queue and power consumption required for the frame sorting process are reduced.

First claim

The invention claimed is:

1. A transfer device comprising:
a processor; and
a storage medium having computer program instructions stored thereon, when executed by the processor, perform to:
monitor, in a communication system to which a network with a PON configuration including a plurality of OLTs between host devices and subordinate devices is applied, downstream frames input from the host devices between the host devices and the OLTs and calculate a statistical value of the downstream frames per a fixed cycle predetermined;

store the downstream frames input from the host devices in a plurality of queues;
input the downstream frames to the plurality of queues; and
determine the number of frames to be sequentially input to the plurality of queues in the frame sorting process and increase a value of the number of distributed frames of at least one of the host devices input to an OLT, the OLT having a smaller value of a total number of frames input from all the host devices than a maximum number of rounded frames obtained by dividing a value of a total number of frames input until the frames of all the host devices take turns around the plurality of queues by the number of OLTs.

2. The transfer device according to claim 1 , wherein
when the number of host devices is p, the number of OLTs is q, a minimum integer exceeding a number obtained by dividing a value of a total number of frames input until the frames of all the host devices take turns around the plurality of queues by the number of OLTs is N, an optical communication speed in a PON section is B, a speed at which a host device i (i is an integer from 1 to p) outputs downstream frames is Ri, the statistical value of the number of downstream frames per the fixed cycle of the host device i is ni, the statistical value of maximum values of downstream frame sizes per the fixed cycle is s, a predetermined delay upper limit is y, and the number of distributed frames of the host device i that the frame sorting unit sequentially inputs to the queue connected to a k-th OLT (k is an integer from 1 to q) is nk, the distribution control unit determines the N to satisfy the following equation

[

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.

9

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N
=

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,

determines the nk to satisfy the following equation based on the determined N

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∑

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=
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ik

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NR
i

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and
when between the N and the nk, the following condition

[

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.

11

]

N
-
1

Assignees

• Nippon Telegraph & Telephone

Inventors

• HARADA Rintaro
• Uzawa Hiroyuki
• Nakamura Hirotaka
• Terada Jun

Classifications

• H04L47/621

  Individual queue per connection or flow, e.g. per VC · CPC title

• H04J14/0239 Primary

  in WDM-PON sharing multiple downstream wavelengths for groups of optical network units [ONU], e.g. multicasting wavelengths · CPC title

• H04Q2011/0064

  Arbitration, scheduling or medium access control aspects · CPC title

• H04L47/56 Primary

  implementing delay-aware scheduling · CPC title

• H04Q11/0067

  Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring · CPC title