Abstract:
Systems and methods of supporting a communication session are provided. A first endpoint is authenticated with a terrestrial wireless communication network, wherein the first endpoint is in wireless communication with a satellite communication network. A quality of service is determined for communications exchanged between the first endpoint and a second endpoint supported by the terrestrial communication network. Communications are exchanged between the first and second endpoints in accordance with the determined quality of service.

Description:
BACKGROUND OF THE INVENTION 
     There are a variety of different types of communication networks, such as terrestrial-based wireless communication networks and satellite communication networks. Terrestrial-based wireless communication networks are commonly known as cellular networks because the network topology revolves around a number of base stations each supporting wireless communication units within a defined region known as a cell. Compared to terrestrial-based wireless communication networks, satellite communication networks have a large number of drawbacks, including the expense of the satellites and the associated handsets. An additional problem with satellite communication networks is the large latency associated with the time required for information to travel between a land-based communication device and the satellite. This delay is then repeated for the transmission of the communication from the satellite back down to another communication device. The delay introduced due to the satellite communication links begins on the order of 500 ms and can exceed 2,500 ms. 
     SUMMARY OF THE INVENTION 
     Current satellite communication networks do not provide quality of service mechanisms to account for delays and/or packet loss. Accordingly, exemplary embodiments of the present invention overcome the above-identified and other deficiencies of conventional systems. 
     Systems and methods of supporting a communication session are provided. A first endpoint is authenticated with a terrestrial wireless communication network, wherein the first endpoint is in wireless communication with a satellite communication network. A quality of service is determined for communications exchanged between the first endpoint and a second endpoint supported by the terrestrial communication network. Communications are exchanged between the first and second endpoints in accordance with the determined quality of service. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         FIG. 1  is a block diagram of an exemplary system in accordance with the present invention; and 
         FIG. 2  is a call flow diagram of an exemplary method in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a block diagram of an exemplary system in accordance with the present invention. The system of  FIG. 1  allows mobile station  104 , which is in wireless communication with a satellite communication network, to communicate with mobile station  102 , which is in wireless communication with a terrestrial-based network (represented in  FIG. 1  by base stations  103  and  105 ). The system can also provide digital video broadcasting to mobile station  104  via the satellite communication network. 
     The exemplary system includes satellite processor  150  coupled to a satellite communication network via satellite uplink component  176  and satellite  182 . Satellite processor  150  is also coupled to a terrestrial-based wireless communication network that includes base stations  103  and  105 . Satellite processor  150  provides advance internet protocol (IP) networking features, such as diversity routing and bandwidth, to support virtual private networks (VPNs) for mobile station  104  such that security can be provided for asynchronous transfer mode (ATM) packets of the satellite communication network. 
     Unlike a conventional base station, base station  105  includes an access service node gateway  114 , home agent  116 , authentication, authorization, accounting and auditing server (AAAA)  118  and core ATM/IP switch/router  120 . Core ATM/IP switch/router  120  can employ a 10BaseT, 100BaseT or 10Base2 connection with interface  152  of satellite processor  150 . Core ATM/IP switch/router  120  can provide rate adaptation for low-speed and high-speed traffic by using pre-assigned port IDs for the different rate traffic. Core ATM/IP switch/router  120  can include routing tables, that are automatically updated, for satellite to wireless routing protocols across the satellite communication network, and RIPV, OSPF or BGP across the terrestrial-based wireless communication network. Moreover, core ATM/IP switch/router  120  can provide satellite communication network to terrestrial-based wireless communication network subnet masking to allow for efficient use of IP addresses. Base transceiver  112  supports a wireless communication link between base station  105  and base station  103  of the terrestrial-based wireless communication network. 
     In the system of  FIG. 1  communications in the satellite communication network are performed using ATM packets and communications in the terrestrial-based wireless communications network are performed using IP packets. Accordingly, satellite processor  150  is coupled to base station  105  by way of ATM and IP interface  152 , which provides an interface between the IP-based terrestrial wireless communication network and the ATM-based satellite communication network. Interface  152  is coupled to ATM virtual path identifier/virtual channel identifier (VPI/VCI) fabric  154 , which acts as a convergence sublayer for incoming IP traffic from the terrestrial-based wireless communication network for transmission over the ATM-based satellite communication network and for outgoing ATM traffic from the satellite communication network for transmission over the IP-based terrestrial wireless communication network. ATM VPI/VCI fabric  154  can perform VCI/VPI address insertion for traffic received from the terrestrial-based wireless communication network. 
     ATM VPI/VCI fabric  154  is coupled to session control module  156 , buffering and delay correction module  158 , queuing and scheduling module  160  and payload processing and prioritization module  162 . Session control module  156  maintains a state event machine for establishment, maintenance and tearing down of connections. It dynamically changes the buffering and scheduling of packets based on channel conditions and feedback information received from applications running on the mobile station  104 . Buffering and delay correction module  158  buffers incoming packets (and purges the oldest living packets that have not been forwarded) and performs delay correction to change the packet size based on service request and channel condition status. Queuing and scheduling module  160  adjusts the delay performance of the applications running on mobile station  104  based on commands received from session control module  156 . For example, queuing and scheduling module  160  provides priority queuing management to support real time, non-real time and contention-based traffic. 
     Payload processing and prioritization module  162  processes incoming control plane packets, connection related signaling messages and user data from both the satellite and terrestrial-based wireless communication networks. Based on the service type request of a particular connection, payload processing and prioritization module  162  allocates the priority for each connection type. 
     Interface  152 , fabric  154  and modules  156 - 162  can be application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) and/or microprocessors executing code embodied on a computer-readable medium. Fabric  154  couples these elements to bus  155 , which in turn is coupled to digital receiver  164 , digital transmitter  166  and memory/clock  168 . Memory/clock  168  is also coupled to digital receiver  164  and digital transmitter  166 , and can include any type of memory, such as RAM, ROM, and/or flash memory. The clock of element  168  acts as a master clock for digital transmitter and receiver  164  and  166  and fabric  154  (via bus  155 ). The memory of element  168  can store locally executable files. Digital receiver  164  is coupled to analog receiver  170 , and digital transmitter  166  is coupled to analog transmitter  172 . Analog receiver  170  and analog transmitter  172  are coupled to each other, and to multiplexer  174 . 
     Multiplexer  174  couples satellite processor  150  to network coordination center (NCS)  178  of satellite uplink component  176 . NCS  178  is in turn coupled to satellite dish  180  which communicates with a satellite-based network, represented in  FIG. 1  by satellite  182 . Satellite  182  then communicates with mobile station  104 . 
       FIG. 2  is a call flow diagram of an exemplary method in accordance with the present invention. Initially, mobile station  104  performs satellite network access authentication with NCS  178  of the satellite network. After authentication with the satellite network, mobile station  104  sends a service request to payload processing and prioritization module  162 , which forwards the message to session control module  156  (step  204 ). Session control module  156  forwards the service request to ATM/IP interface  152  (step  206 ), which then forwards the service request to base station  105 . Base station  105  accesses information from AAAA server  118  and then sends an authentication request to interface  152 , which in turn, sends the authentication request to session control module  156  (step  208 ). 
     Session control module  156  forwards the authentication request to mobile station  104  (step  210 ), which responds with an authentication response (step  212 ). Session control module  156  forwards the authentication response to interface  152  (step  214 ), which forwards the authentication response to base station  105 . Base station  105  authenticates the mobile station using AAAA server  118 , accesses a service profile for the mobile station from home agent  116 , and provides interface  152  with the requested service profile. Interface  152  forwards the service profile to session control module  156  (step  216 ). Service control module  156  uses the service profile to provide quality of service for the mobile station supported by the satellite communication network. 
     Session control module  156 , based on the requested service profile, sends service specific queuing and scheduling initialization information to queuing and scheduling module  160  (step  218 ). Session control module  156 , based on the requested service profile, sends service specific buffering allocations to buffering and delay correction module  158  (step  220 ). Session control module  156  then forwards the requested service profile to mobile station  104  (step  222 ). 
     When interface  152  receives user data for mobile station  104 , the interface sends the user data to payload processing and prioritization module  162  (step  224 ), which then sends the user data to buffering and delay correction module  158  (step  226 ). Based on the service profile, buffering and delay correction module  158  sends the user data to fabric  154  (step  228 ), which forwards the user data to mobile station  104 . This process will be repeated for all user data transmitted to mobile station  104 . 
     Based upon the received user data, mobile station  104  sends service performance feedback information (step  230 ) to payload processing and prioritization module  162 , which forwards the information to session control module  156 . Session control module  156 , based upon the service profile and service performance feedback information, provides corrective actions to queuing and scheduling module  160  and buffering and delay correction module  158  (step  232 ). 
     When mobile station  104  desires to terminate the communication, the mobile station sends a service clear request to session control module  156  (step  234 ), which then informs buffering and delay correction module  158  of the service clear request (step  236 ) and forwards the information to fabric  152  (step  238 ), which then informs base station  105  of the clear request. 
     As can be seen from the discussion above, exemplary embodiments of the present invention provide for on-demand service provisioning and end-to-end Quality of Service (QoS) for mobile stations in wireless communication with a satellite communication network, which increases end-user satisfaction. 
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.