Network Engineering SessionAPAN Conference 2004 in Cairns

July 4, 2004

e-VLBI Update and E2E Performance

Masaki Hirabaru David Lapsley Yasuhiro Koyama

NICT KoganeiJapan

MIT Haystack Observatory, USA

NICT KashimaSpace Center, Japan

masaki@nict.go.jp dlapsley@haystack.mit.edu koyama@nict.go.jp

VLBI (Very Long Baseline Interferometry)de

lay

radio signal from a star

correlator

A/D clockA/D

　Internet

clock

•e-VLBI geographically distributed observation, interconnecting radio antennas over the world

•Gigabit / real-time VLBI multi-gigabit rate sampling

High Bandwidth – Delay Product Network issue

ASTRONOMYGEODESY

~Gbps~Gbps

Two Recent Experiments of UT1-UTC Estimation

• July 23 4am-6am JST (tsev7) Kashima was connected at 100M.NIC hardware error was reported.

• July 30 4am-6am JST (tsev8)Kashima was upgraded to 1G through JGN II 10G link.All processing done in ~4.5 hours (last time ~21 hours)Average ~30 Mbps transfer by bbftp (under investigation)

test

experiment

Koganei12GCF

1 Gbps

1 Gbps

1 Gbps

e-VLBI Network Configuration (Japan side)

NICT Koganei (north)

12GCF

TransPAC

OC192

GS4000

L2

203.181.248.200/30

203.181.194.48/28203.181.194.0/28

U-node

JGN IIJGN II

NICTKoganei (south)

KDDI Otemachi

GbE x2

OC48 (ATM)

L2

NICT Kashima (34m)

GbE x2

e-VLBI for TransPAC

U-node

Domestic VLBI network

OC48+GbE

L2

GbE x2

VLBI

1

vlbi2

vlbi-perf1

vlbi-bwctl

50

51

52

GbEGbE x2

koganei-perf1

koganei-perf2

2

3

GS4000

GS4000

49

201

202MS3 tpr2

OC192

GbE10G

tpr410G

PRO

JGN IIJGN II

NICT Kashima (main)

From Kashima to Washington DC

From Tokyo (perf5) to Washington DC (kame)

　

KwangjuBusan

2.5G

Fukuoka

Korea

                                       

2.5G SONET

KORENTaegu

Daejon

10G

1G1G

1G

Seoul XP

Genkai XP

Kitakyushu

Kashima

1G

Fukuoka Japan

250km

1,000km2.5G

TransPAC

9,000km

4,000km

Los Angeles

Cicago

New York

MIT Haystack

10G

2.4G x2

APII/JGNII

Abilene

Koganei

1G

Indianapolis

100kmbwctl server

Network Diagram for e-VLBI 2004 planand TransPAC/I2 bwctl servers

1G x2

Tokyo XP

*Info and key exchange page needed like:http://e2epi.internet2.edu/pipes/ami/bwctl/

perf server

e-vlbi server

– Done 1 Gbps upgrade at Kashima

– Planned 2.5 Gbps upgrade at Haystack– Experiments using 1 Gbps and more – Using real-time correlation

JGNII

e-VLBI:

E2E Measurement for High Bandwidth-Delay Product Network(backbone ~ access)

• UDP – not TCP friendly

• TCP – Long time to get average (~ 30 minutes) Depends on TCP implementations

TCP peak rate (Slow start)

Available bandwidth

http://mrtg.koganei.itrc.net/mrtg/tcp/

Scheduled Test:

On-Demand Test:• iperf only – difficult to see the reason

iperf (bwctl) with web100 kernel

TCP behavior

http://mrtg.koganei.itrc.net/cgi-bin/web100plot.cgi?server=203.181.194.51

TCP Peak Rate in Japan and Korea

Kashima - Tokyo

Busan - Tokyo

Fukuoka - Tokyo

Plans

•The 3rd e-VLBI WorkshopOctober 6-7, 2004, Makuhari Japan

e-VLBI:

Performance test:• with Internet2/piPES

• will be a part of Global Observatory

Backup

bwctl – iperf wrapper

bwctld bwctld

bwctl

Host A

iperfiperf

Username &password

Run &response

Host B

NTP

APAN JP Maps written in perl and fig2div