This paper presented the virtual telephony network, P_VPN. The architecture of P_VPN includes management layer, transmission layer and control plane.

文章提出了电话虚拟专网P_ VPN安全模型，其体系包括管理层、传输层和控制面。

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The telecommuting boom has been driven in part by the rapid penetration of broadband in the home, easier and cheaper forms of IP telephony, more robust VPN (virtual private network) software, plus a new generation of powerful laptops that are true desktop replacements.

ECONOMIST: Tech.view