An object of this type indicates a set of CM MAC bridge interfaces, encoded as a BITS syntax with a ?1?Bit for each interface included in the set.Bit position eCM(0) represents a conceptual interface to the internal ‘self’ host MAC of the eCM itself. All other bit positions K correspond to CM MAC bridge port interfaceindex with ifIndex value K. A BITS object is encoded as an OCTET STRING, which may havelength zero. Bit position 0 is encoded in the mostsignificant bit of the first octet, proceeding to bit position 7 in the least significant bit. Bit position 8is encoded in the most significant bit of the second octet,and so on.In a CM, ifIndex value 1 corresponds to the primary CPE interface. In CableHome devices, this interface is assignedto the embedded Portal Services (ePS) host interface, whichprovides a portal to the primary physical CPE interface. In many contexts of a DocsL2VpnIfList, a ‘1’ in bit position 1 corresponds to ‘any’ or ‘all’ CPE interfaces when the CM contains more than one CPE interface. ifIndex value 2 corresponds to the docsCableMacLayer RF MAC interface. ifIndex values 3 and 4 correspond to the docsCableDownstream and docsCableUpstream interfaces, respectively, which are not separate MAC bridge port interfaces. Bit positions 3 and 4 are unused in this type;they must be saved and reported as configured, but otherwise ignored. ifIndex values 5 through 15 are reserved for individualCPE interfaces for devices that implement more than oneCPE interface. In such devices, DocsL2vpnIfList bit position 1 corresponds to the set of all CPE interfaces.A CM with more than one CPE interface MAY assign a DocsL2vpnIfList bit position within the range of 5..15 torefer to the single primary CPE interface.ifIndex value 16 is assigned to any embedded Multimedia Terminal Adapter (eMTA) as defined by PacketCable.ifIndex value 17 is assigned to the IP management host interface of an embedded Set Top Box (eSTB). ifIndex value 18 is reserved for the DOCSIS Set-top Gateway (DSG) trafficdelivered to an eSTB. ifIndex values 19 through 31 arereserved for future defined embedded Service Application.