Hardware configuration, support node and method for implementing general packet radio services over gsm

The present invention relates to a hardware configuration, general packet radio service support node and method for realizing general line radio service (GPRS) in mobile global system communication.

This section introduces various aspects of the art that relate to the various aspects of the invention described and / or claimed below. The discussion here is effective in providing background information of the invention and facilitates an accurate understanding of various aspects of the invention. Therefore, it should be understood that the following description should be read from this point of view and is not intended to understand the prior art.

General Line Radio Service (GPRS) is a new standard of the European Telecommunications Standards Institute (ETSI) for a new bearer service set, which is already expanding its useful services in mobile global system (GSM) communications. GPRS is based on the end-to-end transfer of packet mode data between users on GSM. To provide both point-to-point (PTP) and point-to-multipoint (PTM) mobile packet data services, GPRS requires packet mode only for overlay networks on GSM.

The network infrastructure that underlies GSM is circuit-switched networks and voice bandwidth. GPRS adds a packet mode data transfer function to GSM. This additional feature of GPRS allows GSM to support a broader repertoire of additional mobile services using packet-mode data transfer. This is crucial given that today's users of cellular technology are demanding access to more database services, such as the Internet and other information services.

The traffic characteristics of packet-mode data that are effectively supported by GPRS range from intermittent, burst data transfers to frequent low volume data transmissions and can range from high volume data transmissions. When the interval between successive transmissions greatly exceeds the average transfer delay time, the data transmission is usually considered as a burst transmission. A service that frequently repeats the transfer of hundreds of octets at a time is a typical small-volume data service, that is, a small-scale message service. A transaction consisting of several kilobytes of data, which occurs at a rate of up to several transactions per hour, is an example of a large amount of data transmission that rarely occurs.

As already pointed out, the system that realizes GPRS must support PTP type and PTM type bearer services, but other GSM services are inevitably due to the nature of circuit-switched operations unique within GSM. It is a PTP type. To implement GPRS, both connectionless and connection-oriented network services in the category of PTP-type services must be supported. Possible PTP-type services include information retrieval, communication services, credit card transactions, monitors, Internet access, and the like.

All PTP-type services are based on the ability to send information from one source to multiple destinations with a single service request. To implement GPRS, it must support three categories: PTM multicast, PTM group call, and IP (Internet Protocol) multicast. PTM multicast allows a user, or subscriber, to send a message to some or all subscribers within a particular geographic area. Group calls (defined in ETSI) send messages only to cells that are known to contain specific recipients joined to the call group. IP multicast is a standard mechanism that allows users belonging to a particular group to exchange messages via the IP protocol suit within GSM. Some possible PTM services can include news or weather forecast distribution, electronic advertising, and all-vehicle dispatching services.

To implement GPRS, it must also support applications based on standard protocols for packet mode data communication. These standard protocols can have well-known, i.e., network-to-network connectivity procedures with existing IP and X.25 networks.

The first important advantage of GPRS is that the radio channels within GPRS are shared among multiple mobile stations (MS). The second advantage is that multiplexing on the air interface can effectively support burst traffic. A third advantage, especially for subscribers, is that GPRS users are charged for the amount of information transferred, not for the connection time connected to the system.

Although the enhancement of GSM by GPRS is a significant advance in cellular communications, there has been no well-known embodiment of GPRS in the past. GPRS requires additional hardware and software, as well as refurbishment of existing GSM networks. The implementation of GPRS must be effective, robust and economical.

<p> Therefore, it is an object of the present invention to provide an effective, robust, and cost effective hardware configuration, general purpose packet radio service support node and method for performing GPRS on GSM.</p>

<p> The above object is achieved by the hardware configuration, general purpose packet radio service support node and method for implementing GPRS in GSM according to the present invention. Some aspects corresponding to the scope of the original claims invention will be described below. These aspects merely give a brief overview of some of the possible forms of the invention and do not limit the scope of the invention. In fact, the present invention includes various aspects not described below. The following description is for the purpose of giving an overview of the present invention, and should not be regarded as the essence of the present invention in any of the following aspects. The present invention is defined separately within the scope of the claims.</p><p> According to one aspect of the present invention, a hardware configuration for implementing a general-purpose packet radio service on a mobile global system communication network is provided. The hardware configuration includes a plurality of electronic boards for realizing a general-purpose packet radio service function. The electronic boards communicate with each other via the internal bus and communicate with other external circuits via the external bus. This communication separation brings a performance advantage. The external bus is preferably an ATM bus that supports voice and / or data services.</p><p> The internal bus is preferably a PCI bus, particularly a compact PCI bus. The plurality of electronic boards include at least one single board computer that executes call control and SNMP management, and further includes at least one channel of processing cards.</p><p> According to another aspect of the present invention, a general line radio service support node (GSN) is provided for supporting general line radio service on a mobile global system communication network. The GSN is a single board computer for realizing the general-purpose packet radio service function required for each call in service, and a line card processor for realizing the general-purpose packet radio service function required for each packet in service. It has. The GSN functions as an SGSN (serving GSN), a GGSN (gateway GSN), or both.</p><p> When acting as an SGSN, the single board computer preferably supports wireless resource management, authentication and mobility management. Radio resource management includes, for example, cell selection management, call route management and U._mIt can consist of interface management. Mobility management can consist, for example, communication line management and logical link establishment, maintenance and cancellation. The line card processor can support, for example, encryption, compression, or routing and tunneling capabilities. When acting as a GGSN, the single board computer preferably supports, for example, session management capabilities. The line card processor can support, for example, an address translation function, an access control function, or a routing and tunneling function.</p><p> According to still another aspect of the present invention, there is provided a method for implementing a general-purpose packet radio service on a mobile global system communication network. The above method supports a step of providing a general-purpose packet radio service support node having first and second arithmetic units, and a general-purpose packet wireless service function required for each call serviced by the first arithmetic unit. This includes a step of supporting a general-purpose packet radio service function required for each packet receiving service from the second arithmetic unit.</p>

<figref num="1">It is a figure which shows the electric communication system for realizing GPRS on GSM.</figref><figref num="2">It is a figure which shows the hardware configuration by one aspect of this invention for realizing GPRS on GSM.</figref><figref num="3">It is a figure which shows the functional division of SGSN which can be carried out by the hardware configuration of FIG. 2 by another aspect of this invention.</figref><figref num="4">It is a figure which shows the functional division of GGSN which can be carried out by the hardware configuration of FIG. 2 by another aspect of this invention.</figref>

Figure 1 outlines the GPRS network 100, which is a system for realizing GPRS. Both the communication source and communication destination are GSM mobile stations (MS) 10 and 20, or terminal equipment (TE) 102. And 104. For illustration purposes, the signal interfaces between the components are shown with dashes, and the data transmission and signal interfaces are shown with a single line. As shown in the figure for TE104, TE102 and 104 can directly access GPRS network 100. Alternatively, the GPRS network 100 can be accessed via an external data network, such as the Packet Data Network (PDN) 106 used for communication with the TE102. MS10 and 20 communicate with GPRS network 100 over a radio channel via a base station system (BSS), which is base station 108.

The mobile terminal (MT) 110 interconnects TE104 and BSS108. MT110 and TE104 are related to this application, such as Digital Cellular Telecommunications System (Phase 2+), General Packet Radio Service (GPRS), Service Description Stage 2, GSM 3.60 of the European Telecommunications Standards Institute (ETSI). Communication is performed using the R interface described in v6.4.0. The serving GPRS support node (SGSN) 112 and the first and second gateway GPRS support nodes (GGSN) 114, 116 are processing packet traffic. As shown in the figure, the first GGSN114 communicates with the public land mobile network (PLMN) 118, and the second GGSN116 communicates with the TE102 via the PDN106. Network 100 further includes a mobile exchange (MSC) / visitor location register (VLR) 120 and a home location register (HLR) 122. Short Message System (SMS) / Gateway Mobile Exchange (GMSC) 121 and SMS / Network Connection MSC (IWMSC) 123 are connected to Short Message-Service Center (SM-SC) 124. The device identification register (EIR) 125 is connected to the SGSN112. FIG. 1 shows various interface modalities, such as the Gb interface between BSS108 and SGSN112. The interface shown in Figure 1 is defined in the ETSI standard for GSM, especially GPRS on GSM.

Next, with reference to FIG. 2, a hardware configuration 200 capable of implementing the GSN platform (GSNP) according to one aspect of the present invention is shown. As discussed in more detail below, GSNP is a platform that supports both SGSN and GGSN features. GSNP is preferably run on the Lucent Technology SPEED platform.

The hardware configuration 200 is an inexpensive, wideband, and easily expandable switching product built on an open architecture using a standard hardware interface and a software interface. The hardware configurations for SGSN112 and GGSN114 or 116 may be the same as long as they can support the features required by the specified standards. The hardware configuration 200 preferably comprises a wideband backplane, a switchline card, an intelligent network interface card, and a channel processing card.

The hardware configuration 200 consists of a PCI bus or internal bus 202, which consists of a single board computer (SBC) 204, a SCSI card 206, an Ethernet interface card 208, an optical carrier level 3 (OC3) interface card 210, and a first. E1 frame relay (FR) interface card 212, automatic voice recognition (ASR) card 214, digital signal processor (DSP) card 216, second E1FR interface card 218, and various external circuits represented by reference number 219. It is interconnected. The PCI bus 202 is preferably a 22-slot compact PCI bus. The cards 204, 206, 208, 210, 212, 214, 216, and 218 are commonly referred to as electronic cards. The ASR card 214 and DSP card 216 are channel processing cards that perform voice coding, echo cancellation, or dual-tone multi-frequency detection / generation.

The SBC card 204 executes call control to control the operation of GSNP and also executes the SNMP management function. The SBC card 204 can advantageously use a commercially available processor such as a Sun Microsystems SPARK -based processor or an Intel Pentium -based processor. The SBC card 204 preferably runs a Solaris UNIX -based operating system.

The PCI bus 202 is preferably 64-bit long and operates at 33 MHz. Compact PCI systems include a variety of compact PCI systems, including SCSI adapters, video adapters, Ethernet network interface controllers (NICs), ATM NICs (such as OC3 interface cards 210), signaling signal 7 (SS7) NICs, and hard drives. Commercially available 3U and 6U circuit packs are available. The PCI bus 202 is preferably a 2 Gbps compact PCI bus and is used for control and packet data transfer. External Asynchronous Transfer Mode (ATM) Bus 220 provides ATM communication within a hardware configuration of 1.4 Gbit / s (expandable to 5.6 Gbit / s) and is used for connection-oriented voice and data traffic. The ATM bus 220 preferably has 16 slots.

OC3 Interface 210 provides an Internet Protocol (IP) that interfaces with Platform 200. The OC3 interface card supports PDN traffic. ASR board 214 supports transmission encryption and compression, if desired. Each E1 The FR boards 212 and 218 preferably include 16 E1 links, a multiple synchronous communication controller, and a reduced instruction set computer (RISC) processor. Switchline cards provide synchronous interfaces (TI, E1, DS3 and E3) and asynchronous interfaces (OC3). The switch line card switches line-side traffic onto the ATM bus 220 and relays other circuit packs on the ATM bus 220 to handle the traffic. Intelligent network interface cards can provide ATM network interfaces (OC3, TI and E1) and Frame Relay network interfaces (TI and E1). The intelligent network interface card is a common MIPS that runs segmentation and assembly (SAR) equipment, high-level data link control (HDLC) control equipment, and VxWorks microchemels to handle high-level protocols. It consists of interface-specific devices such as the R4700 microprocessor core. VxWorks is a real-time operating system (RTOS) sold by Winder River Systems in Alameda, California.

The channel processing card includes a DSP card 216 and an ASR card 214, which contains a common R4700 processor core running VxWorks and an array of 40 DSP cards. The array provides an aggregate with a signal processing capacity of 4,000 MIPS for voice coding, echo cancellation, and dual tone multi-frequency (DTMF) detection / generation. The DSP card 216 accesses the PIC bus 202 and the ATM bus 220, allowing it to handle traffic from either the switchline card or the intelligent NIC.

Next, the functions, designs and operations of SGSN112 and GGSN114,116 will be described together with GSNP300 in the light of FIGS. 3 and 4. SGSN112 and GGSN114,116 are collectively referred to by GSN for the sake of brevity and simplicity. The functional configuration according to the present invention provides significant performance advantages over conventional systems. According to one aspect of the invention, the GPRS functionality required for each call in service (ie, on a call-by-call basis, and thus necessarily global) is provided by the single board computer, or generally the first arithmetic unit. Executed or supported. Conversely, the GPRS functionality required for each packet in service is performed or supported by a line card processor, or generally a second arithmetic unit. As shown below through performance calculation, such a functional configuration realizes high performance while keeping the necessary hardware at low cost.

FIG. 3 shows a design example of SGSN112 according to one aspect of the present invention in a functional diagram. SGSN112 is a node that services MS10 and 20 by supporting the Gb interface. The Gb interface is an interface with MS as defined in the ETSI GSM standard. When the GPRS is connected, the SGSN112 sets up a mobility management context that contains, for example, information about the mobility and security of a particular MS10 or 20.

With the initiation of the Packet Data Protocol (PDP) context activation, the SGSN112 sets the PDP context used for routing inside the PLMN118 in relation to the GGSN116 used by GPRS subscribers. The functions of SGSN112 and GGSN116 can be combined within the same physical node, or can be resident in individual physical nodes. SGSN112 and GGSN116 include an IP routing function and can be interconnected with an IP router. If the SGSN112 and GGSN116 are in different PLMNs, the SGSN112 and GGSN116 are connected via the Gp interface. When SGSN112 and GGSN114 are in the same PLMN, SGSN112 and GGSN116 are connected via the Gn interface. The Gp interface provides a function that adds the security function required for communication between PLMNs to the Gn interface. The SGSN112 can transmit location information to the MSC / VLR120 via an optional Gs interface. A paging request can also be sent from the MSC / VLR120 to the SGSN112 using the Gs interface.

Key features of the SGSN112 include mobility management, mobile station authentication, data encryption, data compression, and wireless resource management. SGSN112 must also handle packet routing and forwarding, address translation, logical link management, packet segmentation / reassembly, and tunneling. SGSN112 receives packets known as packet traffic in the aggregate from BSS108 via Frame Relay on E1 (Gb interface). The received packet is subjected to processing such as compression, encryption, and segmentation by SGSN112, and then packet traffic is sent to GGSN114 and forwarded to PDN106.

The GGSN114 is accessed by PDN106 based on the IP addressability of the user data. The IP addressability of the user data contains routing information for GPRS users connected to network 100. Using the routing information, the packet data unit (PDU) is tunneled to the current location of the MS10 connectivity mechanism. The current point of the connection mechanism is, for example, SGSN112. The GGSN114 can request location information from the HLR120 via an optional Gc interface.

Logical functions that must be performed within GPRS Network 100 include functions such as network access control, packet routing and forwarding, mobility management, logical link management, and radio resource management, and then these. The function of is briefly explained. The network access control function is a function that connects a user to the GPRS network 100 in order to utilize the services and / or equipment of the network 100 by using a defined access protocol and a set of procedures. User network access occurs from either a mobile communication device on the GPRS network 100, such as the MS10, or a fixed communication device, such as the TE102. The network interface for fixed communication devices can support multiple access protocols for external data networks such as X2.5 or IP.

Some of the key functions of network access control are described below. The registration function is a means for associating a user's mobile identification (ID) with an address in the user's packet data protocol and PLMN. The authentication and authorization function 302 is a function that verifies the validity of a service request type in order to identify and confirm the service requester and allow the user to use a specific network service. The approval control function is a function that calculates the network resources required to provide the required quality of service (QoS), determines the availability of these resources, and reserves them. This approval control function is executed in cooperation with the radio resource management function.

The packet route specification and forwarding function is a function that determines and uses a message transmission route within PLMN118 or between PLMNs according to a rule set. The key functions of the packet routing and forwarding functions are the relay function, the routing function 304, the address translation and mapping function, the encapsulation function, the tunneling function 306, the compression function 308, and the encryption function 310. The relay function is a means for causing a node to transfer data received from one node to the next node in the data path.

The routing function 304 is a function that uses the destination address of the message to determine the GGSN to which the message should be forwarded and the basic service used to reach the GGSN. The route specification function 304 selects a transmission route to the next destination in the packet route.

Data transmission between GSNs is done via an external data network with its own internal routing capabilities, such as X.25, Frame Relay or ATM networks. The address translation and mapping function is a function that translates an address of a certain type into another address of a different type. This address translation feature can be used to translate an external network protocol address into an internal network address and use it to route packets within and between PLMNs.

The encapsulation function is a function that adds address and control information to a data unit in order to specify the route of packets within and between PLMNs. The decapsulation function is a function that removes the address and control information from the packet and returns it to the original data unit. The tunneling function 306 is a function for transferring encapsulated data from an encapsulated point to a decapsulated point within and between PLMNs. A tunnel is a bidirectional two-point route. Only the tunnel termination point is identified.

The compression function 308 is a function that optimizes the use of radio path capacitance by transmitting the smallest possible standard data unit (SDU). The encryption function 310 is a function that maintains the confidentiality of user data and the confidentiality of signals between radio channels by encrypting and decrypting user data.

The mobility management function 312 is a function that keeps track of the current position of the MS in the PLMN. The mobility management function 312 can include a logical link management function 314 and a logical link establishment / maintenance / release (LLE / M / R) function 316. The logical link management function 314 is a function for maintaining communication between the MS and PLMN across wireless interfaces. The LLE / M / R function 316 establishes communication when the MS is connected to GPRS, monitors the logical link status, manages changes in the link state, and deallocates resources related to the logical link connection. It is a function.

The wireless resource management function 318 is a function related to the allocation and maintenance of wireless communication paths. GSM radio resources are shared between circuit mode (voice and data) services and GPRS. The radio resource management function 318 can include a Um management function 320, a cell selection function 322, and a route management function 324. The Um management function 320 is a function that manages the physical channels used in each cell and determines the amount of radio resources allocated to GPRS in each cell. The amount of radio resources allocated to GPRS varies from cell to cell at the request of premises users. The cell selection function 322 is a function that enables the MS to select the optimum cell used to establish a communication path with the PLMN. In this selection process, it is necessary to measure and evaluate the signal quality from neighboring cells, and to detect and avoid congestion in a specific candidate cell. The route management function 324 is a function for managing the packet data communication route between the BSS and the serving GSN node. The establishment and cancellation of these communication paths may be dynamic depending on the amount of data traffic, or static depending on the maximum expected load in each cell.

According to the present invention, the GSNP300 provides an application with a normal environment based on standard operating systems and communication services, a concise set of application program interfaces (APIs) for hardware management, media stream processing, and an SNMP management framework. ing. The GSNP300 software can extend a wide variety of access modes and support a variety of telephone technology and data applications that extend the range of reliability to cost ratios. For example, the GSNP300 has the advantages of various software.

The software can provide operating system services. SBC204 is running Solaris UNIX S. The MIPS R4700 processor built into the intelligent NIC and channel processing card runs VxWorks. The application software can be run in any environment. Embedded processors are typically used for real-time processing of critical traffic, and SBC204 is used to control plane signals and element management.

Communication service applications access various communication services in both Solaris and VxWorks environments. You can take advantage of TCP / IP networking, native ATM and Frame Relay networking, and backplane IP networking through a regular socket interface. Backplane IP networking makes it possible to consider the backplane as an IP subnet with each card on a bus that has its own IP address on the subnet. Hardware management services running within Solaris or VxWorks Application software can access hardware management services such as resource inventory management and status, connection management and diagnostics via the GSNP300 API. The same services are provided to the external network management system (NMS) 328 via the SNMP agent 326 and the SNMP agent 326.

The GSNP300 offers applications for a number of middleware options. For example, you can run the TinkerTool middleware package to bring UNIX and VxWorks tasks into the same standard event-driven run-to-compression programming environment, as described in the SPEED architecture documentation. Services in this environment include application event handler registering / dispatching, interprocess / processor datagram communication, finite state machines and event logging. The channel processing framework can be used for application protocol / media processing software residing on DSP card 216. The Protocol Streams Framework provides a flexible object-oriented environment for developing and configuring protocol streams.

The GSNP300 supports transmission and signaling plane protocols. To illustrate this, it is assumed that the underlying transfer protocol is Frame Relay. Higher layer protocols are TCP / UDP over IP and GTP (GPRS Tunneling Protocol). Signaling protocols include SS7-based MAP and other existing GSM protocols. See the ETSI standard for additional information on the GPRS protocol. Some configurations of the protocol in SGSN 112 and GGSN 114 or 116 according to one aspect of the invention will be described below.

Figure 3 shows the SGSN112's functional splits and the protocol stacks supported on the GSNP300. SGSN112 is divided into two processing elements, as indicated by the dash line 301. Its processing elements are the SBC204 on one side and the line card processor (MIPS) on the other, which can be placed on line cards such as the E1 cards 212 and 218. R4700), a line card processor circuit 205 consisting of a DSP card 216 or an ASR card 214. For illustration purposes, the E1 card 212 or 218 shall serve to terminate the traffic plane associated with the GPRS protocol, such as SNDCP, LLC, BSSGB, GTP, and the lower layers of the SS7 protocol stack (MTP2, MTP3, etc.). To do. In contrast to the packet-by-packet basis, the functions required for the call-by-call basis, such as mobility management function 312, radio resource management function 318, policing function 227, and authentication function 302, are assigned to SBC204. A line card that can be used in favor of the present invention is disclosed in a co-pending US patent application entitled "Line Card for Supporting Circuit and Packet Switching" by Chakrabarti et al. Has been done.

The SNMP agent 326, which manages and maintains the SGSN112, is assigned to run on the SBS204. An external link is provided between the SNMP agent 326 and the NMS 328 to perform auxiliary post-processing of the measurement data. The upper layer 329 of the SS7 protocol stack, such as the SCCP layer and the TCAP layer, is supplied to the SS7 server on SBC204. The measurement function 333 on the SBC204 measures the parameters associated with the call being processed. The E1 card 214 has dedicated hardware for Level 1 and Level 2 frame processing, leaving ancillary CPU cycles for the R4700 processor for data protocol processing. The lower layers 332 of the SS7 protocol stack, such as the MTP2 layer and the E1 layer, are processed on the line card processor circuit 205.

Both Cryptographic 310 and Compressed 308 operations are highly compute-bound and can easily run out of CPU cycles on the R4700 processor. The encryption and compression operations are preferably performed by the DSP board 216 on the line card processor circuit 205, which is advantageous. The DSP board 216 consists of 30 to 40 DSPs, each running at 100 MIPS, performing effective and cost-effective traffic encryption and compression.

FIG. 4 shows the software division, that is, the functional division of the GGSN114 based on the GSNP300. As will be appreciated by engineers in the field, this software split can be applied to the GGSN116 as well. Functions assigned to the SBC204 typically consist of session management 402 and GGSN management 404. The GGSN management 404 can typically have functions related to the operation, management, and maintenance of the GGSN114. Address translation 406, access control 408, routing 410, and tunneling 412 are assigned to the linecard R4700 processor. This functional split is indicated by the dash line 401. The configuration of protocol stack 414 supported by GGSN114 is shown and includes GTP416, TCP / UDP418, IP420, and E1424. Data traffic is input from SGSN112 to GGSN114. IP-based data traffic is carried from the GGSN114 to the PDN. The GGSN114 terminates the Gn interface (from SGSN112) and the Gi interface (to PDN106).

Next, we consider the typical performance engineering of GPRS applications with respect to the GSNP300. Assume the following two performance conditions. (a) Support 1,000 active sessions or users with each user-transmitted packet with a CSI-coded data rate of 9.05 Kbps. (b) Each user is using only one time slot.

Under these assumptions, the sizing of SGSN112 on the GSNP300 can be completed. The E1 board 212 or 218 can maintain a data rate of 512xDS0, which is approximately 32Mbps overall. Therefore, 1,000 subscribers, each traveling at 9.05 Kbps, can generate aggregate data of about 9 Mbps. The E1 board is running at 28% of the total line rate. The R4700 processor running at 120MHz (100MIPS) on the E1 board can process 50,000 AAL0 packets per second, assuming each packet length is 53 bytes. 9Mbps data traffic is generating about 21,000 packets per second. Therefore, a single E1 board can operate as an SGSN and fully support 1,000 channels. This disclosure will reveal other variants (various data encoding schemes and data rates) to engineers in the art.

According to another aspect of the present invention, the DSP board 216 is used to encrypt 310 and compress 308 data. Each DSP board 216 has 40 DSPs running at 100 MIPS, and it is preferable to realize 4,000 MIPS in total. All data traffic that requires encryption or decryption and / or compression or decompression will be routed through the DSP board 216. Assuming 0.5 MIPS for the encryption of one 64 Kbps data stream, 1,000 users would need a total of 500 MIPS, but with a data rate of only 9 Kbps per channel for CS1 encoding. Therefore, the MIPS required for encryption in the present invention is much smaller than 500 MIPS. Bit-level compression is a CPU-intensive activity and currently estimates require 1-2 DSP MIPS for compression of 9-14 Kbps data channels. In the present invention, since the data rate is around 9 Kbps, 1,000 channels can be compressed at 1,000 to 2,000 MIPS.

The E1 card with the GGSN function, which can play the role of GGSN as well as SGSN, is divided as shown in FIG. If the volume of data traffic is low, the E1 card can also be operated as an SGSN and GGSN. GPRS allows up to 8 time slots per user on the air interface. A user with eight time slots can generate 140 Kbps of data including all overheads. The GPSN300 can have up to 16 E1 / T1 boards and therefore can have up to 16x512 channels. The total data input rate that the GSNP300 can support is therefore 16x512x64 or 524Mbps. Multiple E1 / T1 boards are required to support 1,000 users. A rough estimate is that the invention can support up to 3,724 users, each running in eight time slots on GSNP.

It is possible to allow a typical calculation of the number of cacheable sessions that can be performed within the present invention. In one embodiment of the invention, each E1 board has a main memory, a DRAM with a cache size of 128 megabytes, and a level 1 cache of 32 kilobytes. There is no Level 2 cache in this embodiment. Supports approximately 3,200 sessions per megabyte, assuming all contextual information is stored in line card main storage and there is 306 bytes of contextual information per active session for both SGSN and GGSN. can do. The number of sessions that can be executed without a cache is about 100.

One SBC would be required for the configurations shown in Figures 3 and 4 for all global operations required on a call-by-call, or session-by-session basis. One SBC can support multiple SGSNs and GGSNs.

The reference numerals in parentheses after the constituent requirements of the invention described in the claims are intended to facilitate the understanding of the invention in association with the constituent requirements and the examples, and should be used in interpreting the claims. Not a thing.

API application program interface ATM asynchronous transfer mode BSS base station system ETSI European Telecommunications Standards Association GGSN gateway GPRS support node GPRS general-purpose packet radio service Global system for GSM mobiles GSN General Packet Radio Service Support Node GSNP GSN platform GTP GPRS tunneling protocol HLR home location register IP internet protocol LLC logical link control MS GSM mobile station PCI Peripheral Component Interconnect PDN packet data network PLMN Public Land Mobile Network PTM point-to-multipoint type PTP point-to-point type SGSN Serving GPRS Support Node SNMP Simple network management protocol TCP transmission control protocol TE terminal equipment UDP user datagram protocol 10,20 GSM Mobile Station (MS) 100 GPRS network 102,104 Terminal equipment (ET) 106 Packet Data Network (PDN) 108 Base Station System (BSS) 110 Mobile terminal (MT) 112 GPRS Support Node (SGSN) 114,116 Gateway GPRS Support Node (GGSN) 118 Public Land Mobile Network (PLMN) 120 Mobile Exchange (MSC) / Visitor Location Register (VLR) 121 Short Message System (SMS) / Gateway Mobile Exchange (GMSC) 122 Home Location Register (HLR) 123 SMS / Network connection MSC (IWMSC) 124 Short Message-Service Center (SM-SC) 125 Device identification register (EIR) Hardware configuration capable of implementing 200 GSNP 202 PIC bus 204 Single Board Computer (SBC) 205 line card processor circuit 206 SCSI card 208 Ethernet interface card 210 Optical Carrier Level 3 (OC3) Interface Card 212,218 E1 Frame Relay (FR) Interface Card 214 Automatic Speech Recognition (ASR) Card 216 Digital Signal Processor (DSP) Card 219 External circuit 220 ATM bus 227 Policing function 300 GSN Platform (GSNP) 301 dash line 302 Authentication and authorization function 304 Route specification function 306 Tunneling function 308 compression function 310 Encryption function 312 Mobility management function 314 Logical link management function 316 Logical link establishment / maintenance / release (LLE / M / R) function 318 Wireless resource management function 320 Um management function 322 Cell selection function 324 Route management function 326 SNMP agent 328 Network Management System (NMS) 329 Upper layer of SS7 protocol stack 227 Policing function 332 Lower layer of SS7 protocol stack 333 Measurement function 402 Session management 404 GGSN management 406 Address translation 408 Access control 410 Route specification 412 Tunneling Protocol stack supported by 414 GGSN114 416 GTP 418 TCP / UDP 420 IP 424 E1