1. CERNET2 DVTS Experiences
Congxiao Bao
Tsinghua University, CERNET

2. Outline Introduction CERNET2 DVTS Experiences Lessons learnt Summary
Configuration
Data flow
Reflector development
Traffic monitoring
User controlled testing tools
Lessons learnt
Summary

3. CERNET Video Experiences
IPv4 unicast and multicast
38 GigaPops in 36 cities
2,200 universities connected
Self-funded operation
High utilization (70%+)
H.323
AccessGrid
DVTS
Easy
Easy if multicast ready
Easy if multicast ready
Not Easy

4. CERNET2 Video Trial Pure IPv6 National Backbone
25 GigaPops in 20 cities
120 universities connected
Free usage
Low utilization (10%)
DVTS (30Mbps) - Distance learning
HDTV(27Mbps) - for VoD
SDTV-uncompressed (280Mbps) - for interactive VC
HDTV-uncompressed(1.2Gbps) - for interactive HDVC
3D DVTS(60Mbps) - for special demo

5. Our Thinking DVTS is a good application
Popular globally
special demand for network support
30Mbps, single video stream
Solve the DVTS transmission problem may help for solving other HP transmission problems
Especially for inter-domain case
CERNET2 provides a test-bed
IPv6
large scale distributed DVTS collaborative environment
DVTS is a good starting point!!!

6. CERNET2 DVTS Trial Connection topology Node configuration Data flow
Reflector development
Traffic monitoring
Website support
User controlled testing tools

7. CERNET2 DVTS Connection Topology
25 DVTS nodes (diameter is about kms)
Bidirectional transmission
750Mbps
DVTS
THU XA WH HF
SJTU GZ CD SY TJ
CHQ XM NJ LZ DL
HAB
CHC JN HZ
CHS ZZ
PKU
BUPT
BUAA
FDU
TJU BJ SH

8. CERNET2 DVTS Node configurationSW
DVTS
Testing server
DVTS
sender
DVTS
receiver

9. DVTS configuration— Ordinary Node
CERNET2 backbone
From reflector
Uni.’s video
Other uni.’s videos
30Mbps
30Mbps
Sender
Receiver
display

10. Node configuration—Central Node (1)
Reflector
array
sender
switch GE
Multicast/unicast
T640
12 receivers
13 receivers
backup
CERNET2
THU sending
Reflector array
Each reflector receives multicast/unicast stream from sender and converts to 12(13)unicast duplicated copies to 25 different IPv6 hosts distributed in 25 Pops
30Mx25=750Mbps

11. Equipment Configuration— Central Node (2)bj wh gz nj sh xa cd sy
tjn
lzh
chq
chs
zhz
hef
jnn
xmn
hzh
dln
chc
hrb
pku
bupt
buaa
fdu
tju
PAD display
array PC
cluster
switch GE
30Mx25=750Mbps
PC cluster
Each PC receives a DVTS stream from one of the 25 Pops, respectively
T640
CERNET2
THU Receiving

12. Data Flow CERNET2 25 DVTS nodes CERNET2 CERNET2 DVTS receiving DVTS
sending
SJTU
XJTU
PKU …… ……
JLU
JLU
CERNET2
CERNET2 GE GE GE GE R R R R R R
switch
switch
switch
switch
PKU 北大
SJTU … … … …
DVTS
receiving
CERNET2 national Center
THU
CERNET2 national center
THU … …
DVTS
sending
JLU 吉大 … …
NMS 网管 DV DV

13. Video Wall

14. Reflector Development
It runs on Linux OS and developed using g++
It supports IPv4 and IPv6
It supports Unicast and multicast (SSM and ASM)
It can reflects 20+ streams with gigabit network card
It will be released as Open source soon
source
reflector S
SSM multicast
unicast

15. Network Traffic Monitoring

16. Website Support

17. User-controlled Testing tools (1)
Open and share the network-application test statistics both for administrators and end-users
Common language
To do the test automatically with the test server at any time without partners
testing servers setup
To do the trouble-shooting hop by hop
Distributed servers in each AS discovery and management

18. User-controlled Testing tools (2)
Key techniques
Testing server
Web-server
Easy access
Dvping
UDP packet/port 8000 (source-destination)/addr(source-destination)/30Mbps
Dvmcast
For DVTS file receiving
For DVTS real streaming echo
Distributed servers management
Dvbeacon
Dvping, internal 1 test/hour

19. User Controlled Testing Support (3)
Web server
dvmcast
dvping
User: tein2
Pass: tein2

20. dvping monitoring
dvbeacon

21. Lessons learnt (1) Large-scale DVTS is possible
Network limitation
30 nodes for unicast
Much more for multicast
PC limitation
CPU/Ethernet card
Integrated tools is very important for trouble-shooting
Isolate network problem and application problem
to do the test hop by hop
Open and share the testing statistics for the administrators and system engineers and end-users
Relieve the load of face-to-face test

22. Lessons Learnt (2) Non-technique factors POC list Website
Find the right person ASAP
Website
Standard configuration manul
Test reports release
Sharing info on common problem solving
Important notice

23. Summary Large-scale DVTS video platform
Unicast
Pure IPv6
Multiple reflectors with multicast feed
Multicast very soon
Large-scale application-specific measurement system
User controlled pre-test tools
Real time network traffic monitoring

24. Thank you!