Here is a list of all namespaces with brief descriptions:

NAEBStream
NAEData
NAEVideo
NAEVoice
NBEMonitor
NBiDomainGenerator
Ncommon_DVModule
Ncommon_GraphCL
Ncommon_LSModule
Ncommon_Routing
NDLMonitor
NDMRnms
NDMRnmsDV
NDMRnmsLS
NDomainTable
NDQMonitor
NeDLMonitor
NFloodMiniTable
NFWQ
NHierarchicalGenerator
NHierarchicalTable
NHopsQoSMEntries
NHopsSingle1Entry
NHopsSingleMEntries
NIListener
NIMultiQoSTable
NInfection
NIQoSAwareMEntries
NIterativeScheduling
NLatencySingle1Entry
NLatencySingleMEntries
NLatGenerator
NMiniTable
NMM_DL_Drop
NMM_DL_Out
NMM_DQ_Drop
NMM_DQ_Out
NMM_eDL_Drop
NMM_eDL_Out
NMM_maxDelay_Out
NMM_maxDelayLimited_Out
NMM_maxPST_Out
NMM_maxWP_Out
NMM_P_Out
NMM_PDQ_Drop
NMM_psDQ_Out
NMM_Simple_Drop
NMM_Simple_Out
NMM_SPort_Drop
NMM_WFQ_Drop
NMM_WFQ_Out
NModularMonitor
NMSimpleGenerator
NMultiMiniTable
NMultiQoSTable
NNSPPSTLatOrHopMEntries
NNSPSimpleDC
NNSPSimpleHopMEntries
NNSPSimpleLatOrHopMEntries
Nomnetpp
NPLQoSAwareMEntries
NQoSAwareMEntries
NQoSDomainGenerator
NQoSTable
NSimpleDV
NSimpleGenerator
NSimpleLS
NSimpleTable
NSingleDomainGenerator
NStaticGenerator
NtDomain
NTKMonitor
NTSimpleDV
NTSimpleLS