Kokusai Denshin Denwa Co., Ltd.

Kokusai Denshin Denwa Kabushiki Kaisha

Kenji Suzuki

Toshihiko Kato

Hiroki Horiuchi

Hisao Watanabe

Sadao Obana

Akira Idoue

Tomohiko Ogishi

Shuji Momomoto

A method and apparatus for monitoring a communication link based on TCP/IP protocol obtains a protocol data unit (PDU) between communication systems. A emulation log is produced by analyzing the PDU in a PDU analysis part. An event sequence log is produced by estimating an event sequence of both communication systems based the emulation log in an event sequence estimation part. The behavior and the internal procedure of TCP is emulated by using the specific TCP state transition specification, internal variables of TCP, internal variables indicating the status and internal procedures in the TCP emulation part.

Method and apparatus for monitoring a communication link based on TCP/IP protocol by emulating behavior of the TCP protocol

An efficient packed encoding rules (EPER) for ASN.1 for efficiently encoding the value to each type of abstract syntax definition, in which structure of an encoding data is divided into three fields of a bit field, an octet field following the bit field, and an offset field selectively added to before the bit field, in the bit field, bit data is set in the order of the abstract syntax definition, in the octet field, octet data in a unit of octet is set in the order of the abstract syntax definition, in the offset field, a length information of bit field is set and, in the bit field, padding is made so that a total length of the offset field and the bit field is an integer multiple of 8 bits, and the offset field is added when the length of bit field is not determined from the abstract syntax definition, thereby eliminating problems of PER.

Efficient packed encoding method for ASN.1

A power source control system is disclosed for a data terminal which is connected to a communication line through a modem and a network control unit. A power source control unit is provided between the modem and the data terminal while interface between the modem and the data terminal is maintained so that when an incoming call to the data terminal is received and detected, a line establishing procedure is immediately executed with resepct to the calling party in place of the data terminal, and a main power source of the data terminal is turned ON, making the data terminal ready for a communication operation.

Power source system for data terminal equipment

Growing community of inventors

Komae, Japan

Kenji Suzuki