Cisco Cisco Prime Network Registrar 8.1 Technical References

 An 

 enterprise ID is followed by an EID length.

AT_VERSION (version)

 A two-component 32 bit number, with 16 bits of major version and 16 bits of minor version.

AT_VPNID (vpnid)

 A 7-byte standard VPN ID, as defined in RFC 2685.

AT_ZEROSIZE (zero-size)

 A sequence of bytes representing certain DHCP options that have an option code and a length, where the length is always zero.