Towards Modeling and Testing of IP Routing Protocols

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Towards Modeling and Testing of IP Routing
Protocols

• Jianping Wu, Zhongjie Li, Xia Yin
• Tsinghua University, P.R.China
• Sophia Antipolis, France
• May. 26, 2003

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contents

• background and problem
• the MP-FSM model of Routing Information
  Processing
• a pragmatic test architecture PADTACC
• a simple test notation RIPTS
• a software tester
• example test cases
• conclusions and future work

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IP Routing Protocols
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Testing

• network communication (NC)
• Basic content of routing protocols test
• FSM, other state based approach
• many researches (not covered in this paper)
• routing information processing (RI-Pro)
• Main content of routing protocols test
• Specified in natural language, no formal model
• challenging research (covered in this paper)

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status

• Formal and automatic testing
• Tsinghua TTCN-1 based, etc
• Agilent RouterTester, etc
• Informal and manual testing
• UNH IOL Interoperability test suite, etc

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TTCN Problem-1 data
START T1 ?C ?D ?A ?B
?C ?D ?Otherwise/Timeout
Post0F ?B ?A
?C ?D ?Otherwise/Timeout
Post0F ?Otherwise/Timeout
Post0F
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TTCN Problem-2 control

• TTCN is not so powerful as C,C
• NC-part testing based on TTCN useful, but not a
  good base to support RI-Pro testing (as preamble,
  postamble, etc)
• RI-Pro testing need a correct, stable and
  function-rich NC-Part service
• PDU code/decode (carry routing information)
• State machines
• Protocol configuration

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design overview
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the mp-FSM model
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verify a state
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test architecture
TTCN-2
PADTACC
Parallel And Distributed Test Architecture with
Centralized-Control
Main Test Component (MTC) Parallel Test Component
(PTC) Coordination Point (CP)
Distributed Communication Utilities (DCU)
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test architecture (contd)
test system
Router Under Test
SR1
ifc1
PC_1
ifc2
SR2
ifc3
SRx
ifcn
PC_m
one Main Tester, several Slave Testers compose
the test system, SRs act as PTCs
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requirements on test notation

• Flexible and Simple to be customized
• Send, Receive and State Verification statements
• Specify parallel behaviors on PCOs
• Formalization and Automation of Test
  Configurations
• RIPTS Routing Information Processing Test Script

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RIPTS
a test step
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software tester
UI User Interface TC-Editor Test Case
Editor TM Test Management AC Auxiliary
Channel TE Test Execution RI-Gen Routing
Information Generation
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Example test scenario 1
N1 10.1.1.0/24 N2 10.1.2.0/24 N3
10.1.3.0/24 IUT interface1 10.1.1.5, metric1
interface2 10.1.2.5, metric2
interface3 10.1.3.5, metric3
LSA Link State Advertisement (OSPF routing
information)
Fig. 10. the TOP2 Test Case Outline
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Example test scenario 2
pco1 send top3_total5.ol pco1 recv empty.ol pco2
recv top3_total5.ol pco3 recv top3_total4.ol pco4
recv empty.ol stop
pco1 recv top3_a0_noaggr.ol pco2 recv
top3_a0_noaggr.ol pco3 recv top3_a1_noaggr.ol pco4
recv top3_a2_stub.ol pause
TestCase 3 TestCfg testcfg1 TestEvents wait all
full
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conclusions

• What and how to test RI processing
• mp-FSM model
• PADTACC architecture
• RIPTS notation
• Software tester
• A groping walk off the TTCN road

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future works

• improve RIPTS and IRIT
• application to similar protocols
• relate to TTCN-3
• external function
• interleave

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Thank you. Comments and Criticisms are welcome.