ETSI ES 203 385描述了实施DOCSIS®第二层的CMTSs和CMs要求 虚拟专用网络（DOCSIS？L2VPN）功能。L2VPN功能允许有线电视运营商向商业用户提供第二层透明局域网服务（TLS） 企业。为了加快上市时间，CM-TR-L2VPN-DG-V02[i.8]为CMTS制造商提供了如何 分阶段实施本文件中规定的要求。相位指定仅适用于 CMTS产品。有线调制解调器预计将支持第一阶段所需的所有L2VPN功能。本文件与CableLabs L2VPN规范CM-SP-L2VPN-I12[i]相对应。 19].

ETSI ES 203 385 describes requirements on both CMTSs and CMs in order to implement a DOCSIS® Layer-2 Virtual Private Network (DOCSIS? L2VPN) feature.The L2VPN feature allows cable operators to offer a Layer 2 Transparent LAN Service (TLS) to commercial enterprises.In order to speed time to market, CM-TR-L2VPN-DG-V02 [i.8] offers guidelines to CMTS manufacturers as to how to phase the implementation of requirements defined in the present document. Phase designations are only applicable to CMTS products. Cable modems are expected to support all required L2VPN features in Phase 1.The present document corresponds to the CableLabs L2VPN specification CM-SP-L2VPN-I12 [i.19].