Integration of OMNeT++ Hybrid TDM/WDM-PON Models into INET

Framework

Kyeong Soo (Joseph) Kim, Ph.D. Senior Lecturer in Networking

Multidisciplinary Nanotechnology Centre

College of Engineering Swansea University

21 March 2011

Virtual NGOA Test Bed

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1.25 Gb/s GPON test bed

Linux HPC cluster

with 22 nodes

Motivation

• To develop a comparative analysis framework and supporting environment (virtual test bed) for next-generation optical access (NGOA) architectures based on user-perceived performances

– Measuring end-to-end, user-level experience of performance (i.e., QoE)

– Traffic generation based on user behaviour models

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Scheduler

Downstream Traffic

Queues

. . .

1:M Passive Splitter

Upstream Traffic

Queues

. . .

Burst-Mode Receiver

MAC Downstream Traffic Queue

Upstream Traffic Queue Modulator

(SOA)

Hybrid TDM/WDM-PON OLT

Hybrid TDM/WDM-PON ONU

1:N AWG

. . .

. . .

Circulator

Tunable Transmitter

Tunable Transmitter

Tunable Receiver

Tunable Receiver

Circulator

. . .

. . .

Hybrid TDM/-WDM-PON

1:2 Passive Splitter 3

INET Integration

• Switching at OLT and ONU

• Optical layer modelling

• ONU Discovery

• Control Frames

4

Switching at OLT and ONU - 1

• Mapping between Ethernet and PON addresses

– PON address in hybrid PON: WDM channel index

• Based on point-to-point model of underlying PON

– No support of broadcasting/multicasting at the PON level

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PON as a point-to-point network

PON (= OLT + ODN + ONUs)

…

…

…

…

UNI SNI

…

…

Switching at OLT and ONU – 2

• Layered diagram of hybrid TDM/WDM-PON

6

Ethernet Switch (Bridge)

PON Layer (Scheduler@OLT)

Optical (WDM) Layer

ODN

Ethernet Switch (Bridge)

PON Layer (MAC@ONU)

Optical (WDM) Layer

1-to-1 mapping between

ports and ONUs (i.e.,

WDM channels)

OLT ONU

Optical Layer Modelling – Transmission and Reception

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TX start

(t1)

TX end

OLT RN (AWG) ONU

Processing starts

as soon as the

1st bit is received

RX event in

normal mode

Beginning of

Grant

RX event in

normal mode

(t2)

TX starts as soon as

the 1st bit is received

We need “flow-through”

reception mode here!

RTT

Hierarchical Model Construction

8

Application

Host (e.g., PC)

ONU (w/ Ethernet Switch)

Service

User

Subscriber (Household)

Overview of Host (User) Node

9

HTTP 1

TCP

UDP

Network and Lower

Layers

HTTP nh

…

FTP 1

FTP nf

…

Video 1

Video nv

…

UNI

Implemented Modules

10

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Streaming Video Traffic Model

• Based on H.264/AVC video traces

– e.g. “Terminator 2” VBR clip from ASU Video Trace Library • Duration: ~10 min

• Frame Size: HD 1280x720p

• Mean frame bit rate: 28.6 Mbit/s

• Interface with OMNeT++/INET through “UDPVideoStream{Svr,Cli}WithTrace” modules:

– Performance metrics: • Decodable frame rate (perceived quality metric)

• Packet end-to-end delay (vector)

• Packet loss rate

• Frame loss rate

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For More Information

• INET-HNRL

– http://kyeongsoo.github.com/inet-hnrl/

• Virtual Test Bed for Next-Generation Optical Access

– http://iat-hnrl.swan.ac.uk/projects/virtual_ngoa_testbed.html

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