Performance Evaluation of the CPE WAN Management Protocol Serafeim Papastefanos NTUA

/ NTUA Outline > Introduction to CWMP > Advantages / disadvantages of CWMP > Performance metrics > Improvements > Results > Implementation details > Conclusions

/ NTUA The CPE WAN Management Protocol (TR-69)

/ NTUA Advantages of CWMP > Usage of TCP Reliability No problem transferring bulk data > Passing through firewalls as HTTP traffic > Avoidance of persistent connections > Usage of XML Extensibility Lots of tools

/ NTUA Disadvantages of CWMP > 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

/ NTUA Performance Metrics > Processing time Decoding and encoding of messages Management process Network delay > Memory requirements > Bandwidth requirements > GetParameterValues and GetParameterValuesResponse messages will be used for measurements

/ NTUA Improvements > Generic parsers DOM – Can also be used for encoding or messages SAX – Encoding has to be done by hand Easy to use – more resource requirements > Non-generic parsers Harder to use – less resource requirements > Compression We reduce the bandwidth requirements but increase the processing time.

/ NTUA Memory requirements

/ NTUA Encoding / decoding time

/ NTUA Compression sizes

/ NTUA Time needed for management

/ NTUA Implementation details > A mini-ITX with a 600 MHz CPU was used. > CWMP client build in C Intels IXML library used for DOM parsing Our implementation of non-generic parser > mallinfo() to measure the DOM tree memory requirements > minilzo library to implement compression > gettimeofday() used to measure time

/ NTUA Conclusions > TR069 has many advantages over NETCONF and SNMP > TR069 benefits from compression of messages, even in high network links > Using SAX or even better non-generic parsers instead of DOM optimizes resource usage and speed