Transcript Performance Evaluation of the CPE WAN Management Protocol

Performance Evaluation of the CPE WAN Management
Protocol
Serafeim Papastefanos
NTUA
www.ist-muse.eu
Outline
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Introduction to CWMP
>
Advantages / disadvantages of CWMP
>
Performance metrics
>
Improvements
>
Results
>
Implementation details
>
Conclusions
ICCS / NTUA
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Public Network
ACS Southbound
Interface
CPE WAN
Management Protocol
Hi-Fi Audio
PC
Operators
Content Providers
Application Providers
Customer Support Representatives
ICCS / NTUA
CPE Parameters
RPC Methods
Home Network
Residential
Gateway
Service Providers
CPE Parameters
SOAP
VoIP Phone
Security
Media Server
TV & Set-Top box
Gaming Console
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Internet Standards
ACS Northbound
Interface
DSL Forum
Defined
Operations
Device Management
Firmware Management
Service Management
AutoProvisioning
BAR
RMA Services
Vendor
Defined
The CPE WAN Management Protocol (TR-69)
HTTP
SSL/TLS
TCP/IP
Advantages of CWMP
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Usage of TCP
•
•
Reliability
No problem transferring bulk data
>
Passing through firewalls as HTTP traffic
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Avoidance of persistent connections
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Usage of XML
•
•
Extensibility
Lots of tools
ICCS / NTUA
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Disadvantages of CWMP
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Usage of XML
•
•
Increased requirements in bandwidth
Increased requirements in resources
–
>
Especially in TR069 clients which are embedded devices
Single ACS
•
This may be an issue in a multi-provider environment
ICCS / NTUA
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Performance Metrics
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Processing time
•
•
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Decoding and encoding of messages
Management process
Network delay
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Memory requirements
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Bandwidth requirements
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GetParameterValues and GetParameterValuesResponse
messages will be used for measurements
ICCS / NTUA
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Improvements
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Generic parsers
•
DOM
–
•
SAX
–
•
>
Encoding has to be done “by hand”
Easy to use – more resource requirements
Non-generic parsers
•
>
Can also be used for encoding or messages
Harder to use – less resource requirements
Compression
•
We reduce the bandwidth requirements but increase the
processing time.
ICCS / NTUA
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Memory requirements
200
GetParameterValues
size / KBytes
180
GetParameterValuesDom
160
GetParameterValuesResponse
140
GetParameterValuesResponseDom
120
100
80
60
40
20
0
0
ICCS / NTUA
50
100
# of state variables
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150
200
Encoding / decoding time
80
DOM time
generic time
Compression time
70
time / ms
60
50
40
30
20
10
0
0
ICCS / NTUA
50
100
# of state variables
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150
200
Compression sizes
50
GetParameterValues
SOAP PDU size (Kbytes)
45
GetParameterValues Bulk
40
GetParameterValues (Compressed)
35
GetParameterValues Bulk
(Compressed)
30
25
20
15
10
5
0
0
ICCS / NTUA
20
40
60
80
100
120
140
Num ber of state variables
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160
180
200
Time needed for management
0,6
0,5
time / s
0,4
0,3
0,2
0,1
0
0
50
100
# of state variables
512/256 kbit
1024/512 kbit
10 Mbit
512/256 kbit comp
1024/512 kbit comp
10 Mbit comp
ICCS / NTUA
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150
200
Implementation details
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A mini-ITX with a 600 MHz CPU was used.
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CWMP client build in C
•
•
Intel’s IXML library used for DOM parsing
Our implementation of non-generic parser
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mallinfo() to measure the DOM tree memory requirements
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minilzo library to implement compression
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gettimeofday() used to measure time
ICCS / NTUA
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Conclusions
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TR069 has many advantages over NETCONF and SNMP
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TR069 benefits from compression of messages, even in high
network links
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Using SAX or even better non-generic parsers instead of DOM
optimizes resource usage and speed
ICCS / NTUA
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