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    ADAPTIVE MEDIUM ACCESS CONTROL SCHEME FOR WIRELESS LAN
    31.
    发明专利
    ADAPTIVE MEDIUM ACCESS CONTROL SCHEME FOR WIRELESS LAN 未知

    公开(公告)号：CA2115211C

    公开(公告)日：1997-09-23

    申请号：CA2115211

    申请日：1994-02-08

    Applicant: IBM

    Inventor： BANTZ DAVID F ,  LAMAIRE RICHARD O ,  KRISHNA ARVIND ,  NATARAJAN KADATHUR S ,  BAUCHOT FREDERIC J ,  AHMADI HAMID

    IPC: H04J3/00 ,  H04B7/24 ,  H04J3/16 ,  H04L12/28 ,  H04L12/56

    Abstract: A Medium Access (MAC) Protocol is utilized for wireless radio access for a plurality of remote stations to a base station on a LAN. The MAC protocol is based on a reservation scheme for user data traffic and a random access technique for control and signalling traffic. There is a time division fixed frame structure in which time is slotted, and time slots are grouped into fixed frames consisting of data and control subframes or periods. The fixed frame structure consists of three periods (A, B, and C) along with their respective headers. The first period, the A period, is the outbound channel which is used exclusively for data transfer from the base station to the remote stations. The following period, the B period, is the inbound channel that is used for contention-free data transfer from the remote stations to the base station. The allocation of the data slots in the A and B periods is performed by the base station. The last period of the frame, designated as the C period, is the control channel used for the transmission of reservation requests and data from the remote stations to the base station in a random-access contention mode using a slotted Aloha protocol. The duration of the three periods may be varied using a movable boundary technique. The base station estimates the number of actively transmitting remote stations utilizing feedback information from the remote stations. This estimate is broadcast to the remote stations as control indicia to control their transmission attempts in the C period, thus yielding high transmission efficiency.

    32.
    发明专利
    未知

    公开(公告)号：ES2166759T3

    公开(公告)日：2002-05-01

    申请号：ES93480099

    申请日：1993-07-16

    Applicant: IBM

    Inventor： AHMADI HAMID ,  GUERIN ROCH ,  GUN LEVENT

    IPC: H04L12/56

    Abstract: In a packet communications network, the addition or deletion of a connection to the network by a user is governed by a link traffic metric which represents the effective capacity of each link in the network which participates in the packet connection route. The link metric is calculated in real-time and updated by simple vector addition or subtraction. Moreover, this link metric is also used to calculate leaky bucket parameters which govern the access of packets to the network once the connection is set up. A packet network using these link metrics and metric generation techniques provides maximum packet throughput while, at the same time, preserving grade of service guarantees.

    33.
    发明专利
    未知

    公开(公告)号：DE69331178D1

    公开(公告)日：2002-01-03

    申请号：DE69331178

    申请日：1993-07-16

    Applicant: IBM

    Inventor： AHMADI HAMID ,  GUERIN ROCH ,  GUN LEVENT

    IPC: H04L12/56

    Abstract: In a packet communications network, the addition or deletion of a connection to the network by a user is governed by a link traffic metric which represents the effective capacity of each link in the network which participates in the packet connection route. The link metric is calculated in real-time and updated by simple vector addition or subtraction. Moreover, this link metric is also used to calculate leaky bucket parameters which govern the access of packets to the network once the connection is set up. A packet network using these link metrics and metric generation techniques provides maximum packet throughput while, at the same time, preserving grade of service guarantees.

    35.
    发明专利
    未知

    公开(公告)号：DE69610761T2

    公开(公告)日：2001-05-10

    申请号：DE69610761

    申请日：1996-01-16

    Applicant: IBM

    Inventor： AHMADI HAMID ,  BAUCHOT JACQUES ,  BONNET ROSELYNE ,  KESSLER ILAN ,  KRISHNA ARVIND ,  LANNE P ,  NAGHSHINEH MAHMOUD ,  SOLER CATHERINE ,  WETTERWALD MARIE

    IPC: G06F13/00 ,  H04B7/26 ,  H04L12/56 ,  H04L29/06 ,  H04L29/12 ,  H04W8/26 ,  H04W40/24 ,  H04W40/26 ,  H04W40/36 ,  H04W80/04 ,  H04W92/02 ,  H04Q7/24

    Abstract: A communications network having a number of routers, a number of base stations and a number of mobile units maintains communications with the mobile units by assigning a unique address known to the routing entities of the network to each mobile unit. By including the mobile units unique address in topology updates of the network, the location of the mobile unit at any time is made known to all routers of the network. That is, once a mobile unit moves into a domain of a new access point and establishes a new link with the new access point, it uses the topology update mechanism of the network to make its new location known to all routers. Once a router of the network receives topology update information specific to the mobile unit's new location, it updates its routing table such that packets destined to the mobile unit are routed in a path which terminates at the mobile unit and contains its new access point.

    38.
    发明专利
    未知

    公开(公告)号：DE69610761D1

    公开(公告)日：2000-11-30

    申请号：DE69610761

    申请日：1996-01-16

    Applicant: IBM

    Inventor： AHMADI HAMID ,  BAUCHOT JACQUES ,  BONNET ROSELYNE ,  KESSLER ILAN ,  KRISHNA ARVIND ,  LANNE P ,  NAGHSHINEH MAHMOUD ,  SOLER CATHERINE ,  WETTERWALD MARIE

    IPC: G06F13/00 ,  H04B7/26 ,  H04L12/56 ,  H04L29/06 ,  H04L29/12 ,  H04W8/26 ,  H04W40/24 ,  H04W40/26 ,  H04W40/36 ,  H04W80/04 ,  H04W92/02 ,  H04Q7/24

    Abstract: A communications network having a number of routers, a number of base stations and a number of mobile units maintains communications with the mobile units by assigning a unique address known to the routing entities of the network to each mobile unit. By including the mobile units unique address in topology updates of the network, the location of the mobile unit at any time is made known to all routers of the network. That is, once a mobile unit moves into a domain of a new access point and establishes a new link with the new access point, it uses the topology update mechanism of the network to make its new location known to all routers. Once a router of the network receives topology update information specific to the mobile unit's new location, it updates its routing table such that packets destined to the mobile unit are routed in a path which terminates at the mobile unit and contains its new access point.

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