Patents by Inventor Mooi Choo Chuah

Mooi Choo Chuah has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7031254
    Abstract: A rate control system is provided for a link between a first node, such as an RNC and a second node, such as a Node B, within a wireless communications system where at least one user is provided a rate over the link as a function of link load. For example, the rate control system sets at least one user to a reduced rate on the link as a function of the rates of a plurality of users on the link. In certain embodiments, the rate control system controls the rate by selecting the size of a transport format block used to transport data for a user over the link during a transmission interval. The size of the transport format block can be selected by changing the number of transport blocks used to form the transport format block as a function of the total user data to be transported over the link at that time. The rate of data offered to the link can be controlled by the way user data is mapped into the transport format blocks used to send user data over the link.
    Type: Grant
    Filed: January 25, 2002
    Date of Patent: April 18, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Santosh P Abraham, Mooi Choo Chuah, Ashwin Sampath, Cem Uygur Saraydar
  • Patent number: 7023884
    Abstract: A new algorithm for clock offset estimation for resources distributed across a network (such as the Internet). By exchanging a sequence of time-stamped messages between pairs of network nodes and separately estimating variable delays for each message direction, present inventive embodiments provide estimates for clock offset between node pairs and the bias of such estimates, thereby to permit more accurate correction. Present inventive algorithms operate in a variety of peer and server network configurations while providing significant improvement in convergence speed and accuracy.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: April 4, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, Daniel R. Jeske, Muralidhran S. Kodialam, Ashwin Sampath, Anlu Yan, On-Ching Yue
  • Patent number: 6993021
    Abstract: A packet encapsulation scheme for multiplexing application sessions—Lightweight IP Encapsulation (LIPE)—is described. An LIPE packet comprises at least one multiplexing header (NH) and associated multimedia data packet (MDP). The LIPE packet uses UDP/IP as transport. An MH field further comprises a 16-bit a user identifier (UID) field, an 11 bit length indicator (LNG) field, a 1 bit “more” (M) field and an optional payload type/class of service (PT/CoS) field comprising 8 bits.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: January 31, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, Wolfgang Fleischer, Anlu Yan, On-Ching Yue
  • Patent number: 6980533
    Abstract: In a wireless internet access system, an access point of a base station and a group of wireless modems communicate over a wireless channel. This wireless channel comprises a sequence of “dwells,” where each dwell represents a period of time, e.g., 20 milli-seconds (ms). Each dwell can convey both uplink (or upstream) and downlink (or downstream) transmissions to, and from, the group of wireless modems. However, in each dwell a particular wireless modem can only communicate half-duplex—either provide an uplink transmission to the access point, or receive a downlink transmission from the access point. The access point load balances, or distributes, the downlink transmissions to the group of wireless modems across the dwells upon detection that some dwells convey more downlink transmissions than other dwells.
    Type: Grant
    Filed: August 29, 2000
    Date of Patent: December 27, 2005
    Assignee: Lucent Technologies Inc.
    Inventors: Santosh P Abraham, Mooi Choo Chuah
  • Patent number: 6970423
    Abstract: A UMTS (Universal Mobile Telecommunications System) core network supports the negotiation of asymmetric traffic classes with a mobile station (MS) (or user equipment (UE)). A new quality of service (QoS) information element (IE) is defined that allows for the MS to negotiate for asymmetric traffic classes.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: November 29, 2005
    Assignee: Lucent Technologies Inc.
    Inventor: Mooi Choo Chuah
  • Patent number: 6917600
    Abstract: Apparatus for transferring packet data incorporates a “hand-off” feature that allows the transfer of an existing PPP connection from one packet server to another packet server. Such a hand-off control message or call continue transaction can be initiated by any of the servers involved in the transactions. For instance, assume an initial arrangement where a point-to-point call is set up and in progress between a user and a private network via a first packet server (e.g., a first Serving LAC) and a second packet server (e.g., an Anchor LAC). If, for example, the user moves out of the region served by the first packet server into a region served by a third packet server (e.g., a second Serving LAC), then a hand-off control message transaction, according to the invention, is initiated. Either the second Serving LAC or the Anchor LAC may initiate the call continue transaction. Alternatively, radius servers respectively associated with the packet servers may be employed to perform the call continue transaction.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: July 12, 2005
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, Girish Rai
  • Patent number: 6839339
    Abstract: A UMTS (Universal Mobile Telecommunications System) core network supports a compression framework that provides for header compression of General Packet Radio Service Tunneling Protocol (GTP)-Encapsulated Packets. In particular; the GTP/UDP(User Datagram Protocol)/IP(Internet Protocol) header is compressed. In addition, the UMTS core network also supports RTP(Real Time Protocol)/UDP/IP header compression independent of the GTP/UDP/IP header compression.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: January 4, 2005
    Assignee: Lucent Technologies Inc.
    Inventor: Mooi Choo Chuah
  • Publication number: 20040266351
    Abstract: An advance over the prior art is achieved through an efficient method for the dynamic selection of frequencies with low occupancy in a manner that results in minimizing the search for such frequencies and the risk of a large of number of nodes choosing the same frequency. A method for dynamically selecting the frequencies according to the invention includes the following parts. A channel loading indicator that determines if the mobile node needs to look for a new channel. A channel search algorithm that quickly determines the new channel to be used. A tracking algorithm that remembers the channels that were most recently determined to be loaded and hence should be avoided in the near future. In one embodiment of the invention a method of selecting frequencies for use by a device in a wireless communications network is presented.
    Type: Application
    Filed: June 30, 2003
    Publication date: December 30, 2004
    Inventors: Mooi Choo Chuah, Kameswara Rao Medapalli
  • Patent number: 6801509
    Abstract: A Network Access Server incorporates a “hand-off” feature that allows the NAS to transfer an existing PPP connection from one NAS to another NAS. In particular, 3 new control messages are defined for use in the NAS. Namely: (i) Continued Call Request, (ii) Continued Call Reply, and (iii) Continued Call Connect. These 3 new control messages comprise a L2TP control message header, message identifier (e.g., continued call request, etc.), and a number of fields.
    Type: Grant
    Filed: May 8, 1998
    Date of Patent: October 5, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, Girish Rai
  • Publication number: 20040184471
    Abstract: Transmission methods for multicast messages and for signaling message responses thereto in communication systems supporting a multicast mode provide that a number of retransmissions of a multicast message may be changed based on a number of receivers of the message. Signaling messages to the multicast message may be transmitted in response to a fixed number of multicast message transmissions, and receivers that have not received the multicast message after the fixed number of transmissions may request further retransmissions up to an additional given number of times. Further, signaling messages may be transmitted at different times or staggered based on a radio condition of the receivers. For example, a first multicast message may be transmitted, and responses from groups of receivers may be listened to for a given period, after which one of a next multicast message and a portion of the first multicast message may be transmitted to the groups.
    Type: Application
    Filed: March 20, 2003
    Publication date: September 23, 2004
    Inventors: Mooi Choo Chuah, Arnab Das, Tingfang Ji
  • Patent number: 6757293
    Abstract: The present invention provides an improved RACH access burst arrangement and frame structure. That is, the invention provides methods and apparatus for supporting more than one access burst length in the UMTS access channel structure. Preferably, two access burst lengths are supported, e.g., 5 ms and 10 ms. Such an arrangement is advantageous in applications where it is beneficial to have fast access latency such as, for example, voice or other forms of real-time traffic. Also, the invention provides methods and apparatus for supporting multiple frame sizes. It is to be appreciated that further enhancement to access latency can be obtained by having the UMTS physical layer support multiple frame sizes. The access burst signal transmitted by a remote terminal over the RACH may be an access request or data packets in the case where the RACH is being utilized for UMTS short message services.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: June 29, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, On-Ching Yue, Qinqing Zhang
  • Patent number: 6735190
    Abstract: Overhead is reduced and packet transport efficiency is increased for a flow of switched packets from a router by identifying a plurality of packets having a common destination node within a network and transmitting at least one control message to establish the flow of switched packets; the at least one control message including: (i) a label mapping message corresponding to the flow of switched packets and (ii) a header removal field. Packet headers corresponding to packets of a switched packet flow are not parsed, therefore either the entire header, or a portion of the header, may be removed from each packet assigned a label. A header removal field is shared among routers while signaling to establish a labeled flow. The header removal field is used to provide header structure information to those routers which will be utilized for transport of the subsequent labeled flow.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: May 11, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, On-Ching Yue
  • Publication number: 20040054924
    Abstract: The present invention provides systems and methods for providing distributed, adaptive IP filtering techniques used in detecting and blocking IP packets involved in DDOS attacks through the use of Bloom Filters and leaky-bucket concepts to identify “attack” flows. In an exemplary embodiment of the present invention, a device tracks certain criteria of all IP packets traveling from IP sources outside a security perimeter to network devices within the security perimeter. The present invention examines the criteria and places them in different classifications in a uniformly random manner, estimates the amount of criteria normally received and then determines when a group of stored classifications is too excessive to be considered normal for a given period of time. After the device determines the criteria that excessive IP packets have in common, the device then determines rules to identify the packets that meet such criteria and filters or blocks so identified packets.
    Type: Application
    Filed: September 3, 2002
    Publication date: March 18, 2004
    Inventors: Mooi Choo Chuah, On-Ching Yue, Wing Cheong Lau
  • Patent number: 6704311
    Abstract: An Internet Protocol (IP)-based network incorporates an application level switching server and a number of packet endpoints. A packet endpoint multiplexes application sessions destined for different packet endpoints into one multiplexed session that is terminated with the application level switching server. The latter extracts each application session (or packets associated therewith) and repackages, or switches, them into other multiplexed sessions such that at least two switched packets are transmitted to different packet endpoints. The multiplexed sessions utilize either RTP/UDP/IP or UDP/IP encapsulation.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: March 9, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, Bharat Tarachand Doshi, Anlu Yan, On-Ching Yue
  • Publication number: 20040032877
    Abstract: In the dynamic access priority method, priority classes with different backoff delays are used to prioritize random access over shared channels and to reduce collision in the presence of a surge of random access requests. Service class information for a plurality of service classes is stored at user equipment. The service class information for a service class includes at least one of a maximum and a minimum back off value; the maximum back off value being indicative of a maximum back off interval and the minimum back off value being indicative of a minimum back off interval. At least one of a maximum and a minimum back off value is determined based on a selected service class of the user equipment, and a back off interval is determined based on the determined back off value. The back off interval indicates a period of time the user equipment waits before the user equipment attempts a transmission.
    Type: Application
    Filed: August 19, 2002
    Publication date: February 19, 2004
    Inventors: Mooi Choo Chuah, Tingfang Ji, Wei Luo
  • Patent number: 6693952
    Abstract: In a Universal Mobile Telecommunications System (UMTS) based wireless system, a channelization code-tree is partitioned into two sets: a permanent set and shared a shared set. Those codes in the permanent set are assigned to low data rate users for the duration of a session, or connection. Those codes in the shared set are assigned to high data rate users on a frame-by-frame basis using a downlink shared (DSCH) channel. The partition boundary between the permanent set and the shared set can be dynamically shifted based on traffic conditions.
    Type: Grant
    Filed: March 16, 1999
    Date of Patent: February 17, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, On-Ching Yue, Qinqing Zhang
  • Publication number: 20040017795
    Abstract: In a UMTS network, each packet data service user requires a dedicated channel (DCH) to transmit at high data rates. However, the number of DCHs available is small due to code and power limitations. Thus many users will have to be allocated the same DCH on a time sharing basis. Such sharing will not impact the quality of service for users whose applications are not delay sensitive and whose traffic generation pattern toggles between transmit and idle states. Such applications include web browsing, FTP sessions and E-mail. The present invention discloses four algorithms that can be used to dynamically allocate DCH channels to a contending user based on the user's need according to its traffic generation.
    Type: Application
    Filed: July 24, 2002
    Publication date: January 29, 2004
    Inventors: Santosh P. Abraham, Ching-Roung Chou, Mooi Choo Chuah, Philip Charles Sapiano, Steven E. Sommars
  • Patent number: 6674765
    Abstract: The present invention provides methods and apparatus for providing access priority in a MAC protocol of a communications system such as, for example, with respect to UMTS RACH. Particularly, the invention introduces several access priority methodologies including: (i) random chip delay access priority (RCDAP); (ii) random backoff based access priority (RBBAP); (iii) variable logical channel based access priority (VLCAP); (iv) UMTS-specific variable logical channel based access priority (VLCAP′); (v) probability based access priority (PBAP); and (vi) retransmission based access priority (REBAP). Each methodology associates some parameter or parameters to access priority classes in order to influence the likelihood of a remote terminal completing a successful access request to a base station.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: January 6, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Mooi Choo Chuah, On-Ching Yue, Qinqing Zhang
  • Publication number: 20040002362
    Abstract: The present invention sets forth a methodology for providing improved downlink backhaul services from a radio network controller (RNC) to a plurality of base stations via a backhaul network that provides Ethernet services. The Ethernet services are provided by a group of provider edge (PE) switches and regular label switch routers (referred to as P switches). Base stations within the network are assigned into clusters, each of the clusters having a cluster ID. The RNC transmits packets to a given switch or switches out on the network based on a cluster ID included within the transmitted packet. The communications traffic is then multicast from at least one last hop switch in the network to candidate base stations on the basis of the cluster ID and an active set within the cluster. Advantageously, the clusters act as subgroups for more easily directing the transmission of the backhaul multicast traffic.
    Type: Application
    Filed: June 28, 2002
    Publication date: January 1, 2004
    Inventors: Mooi Choo Chuah, Enrique Hernandez-Valencia, Wing Cheong Lau
  • Publication number: 20030233478
    Abstract: A method, apparatus, system, and computer software for compressing and decompressing a message for transmission. The method of compressing a text message for transmission may include parsing text strings and encoding numerical values with a binary representation and analyzing values of the text strings and populating a session specific codebook with partial strings from the values.
    Type: Application
    Filed: June 17, 2002
    Publication date: December 18, 2003
    Inventors: Mooi Choo Chuah, Tingfang JI, Subhasis Laha