In this paper, we explore a framework model for supportingonline VPNs with different QoS requirements over opticalWDMnetworks. We formulate the online problem inwhich a physical topology and set of VPNs are provided.VPN applications can be classiﬁed into the following types:CBR, VBR and UBR, or ABR. The proposed QoS modelis intended to guarantee diverse QoS requirements ofdifferent VPNs, especially those with very stringent delayjitter requirement and those with a bursty characteristic.Therefore, online VPN over optical networks can provideservice for real-time trafﬁc, e.g. various multimediaapplications. We compare static VPN and dynamic VPNwith the same trafﬁc loading and network conﬁguration.We ﬁnd that the static VPN has better performence insystems with a large buffer, and dynamic VPN has betterperformance in networks without a large buffer. We presentthe basic performance analysis and demonstrate bysimulation that we can provide different QoS for differentpackets from different kinds of VPNs. In addition, we studythe performance of networks with different system parameters, e.g. different proportions of the different trafﬁctypes, and systems with and without buffer.