This is defined by the control vector X'64' and contains the IP characteristics of a TN3270E LU. These characteristics include the IP address of the LU, the port name associated with the LU, and the name of the LU's domain name server, if any. When the SME receives this vector during initial or secondary authorization, or during initial or final accounting, the SME can use these characteristics of the TN3270 LU as part of its authentication logic. See SNA Formats, GA273136 for more information about the TCP/IP information control vector.