Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W24/00—Supervisory, monitoring or testing arrangements
  • H04W24/02—Arrangements for optimising operational condition
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F8/00—Arrangements for software engineering
  • G06F8/60—Software deployment
  • G06F8/65—Updates
  • G06F8/656—Updates while running

Definitions

• the present invention relates generally to software loading in cellular telecommunication systems, and it pertains in particular to a method of loading software in the background while maintaining voice or data traffic.
• Software loading plays a significant role in the operation of complex electronic equipment such as cellular telecommunication systems.
• software loading is necessary in several instances.
• the functionality of modern cellular systems is, to a large extent, controlled by software.
• One common motivation for software loading is to provide system upgrades in the form of migratory releases of predetermined software packages.
• functional changes and enhancements may be added and activated by newly installed software.
• an analog network operating on the Advanced Mobile Phone System (AMPS) can be upgraded to a Digital Advanced Mobile Phone System (D- AMPS) with relatively minor hardware modifications which are activated by new software.
• AMPS Advanced Mobile Phone System
• D- AMPS Digital Advanced Mobile Phone System
• FIG. 1 illustrates a current method for loading software in a typical cellular network.
• a computer terminal 10 used for loading software is coupled to a mobile switching center (MSC) 12.
• MSC 12 mobile switching center
• Terminal 10 generally located at the same site as MSC 12, permits loading from a centralized location.
• MSC 12 is linked to a plurality of base stations by way of a high speed digital connection, such as a pulse code modulation (PCM) link.
• PCM link is an optical or wired link capable of efficiently delivering digital data over vast distances in accordance with a specified standard.
• One widely used standard link is a Tl link 14 which specifies transmission of data at 1.544 Mb/s.
• the Tl standard specifies the transmission of twenty four timeslots, where one timeslot corresponds to one analog conversation (AMPS) or three conversations in digital mode (D-AMPS). Of the twenty four timeslots, twenty three are used for carrying voice data and one, timeslot 9, is reserved for the transmission of control information. It is desirable to utilize the same transmission link for transporting both voice and software data to maximize efficiency, therefore, timeslot 9 is used to carry software data during loading.
• AMPS analog conversation
• D-AMPS digital mode
• timeslot 9 is used to carry software data during loading.
• Tl link 14 couples MSC 12 to base station one (BS1) for efficient high speed communication between the components.
• Base stations typically contain anywhere from eight to seventy two devices wherein each can include, for example, a transmitter and receiver (i.e. transceiver), Location Verification Module (LVM), Radio Frequency Test Loop (RFTL), Combiner Tuner Controller (CTC), or other microprocessor equipped units.
• the procedure for software loading requires that each of the devices be taken off-line or set in an idle state during loading. This is commonly referred to in the industry as "blocking" the device and must be done sequentially for each device prior to loading. Since it may take anywhere from seconds to several tens of seconds to load each device, it is readily apparent that the software loading may take a significant amount of time.
• each base station will have software loaded in its devices in a similar sequential fashion.
• MSC 12 is coupled to BS2 via Tl link 17 and BS3 is coupled to MSC 12 via Tl link 19.
• a complete software load for the entire network can take anywhere from several minutes to hours or even days.
• each device is "forced" out of service for a specific period of time. While out of service, the devices cannot serve traffic thereby depriving cellular operators of potential revenue.
• the current method is cumbersome, inefficient and time consuming thereby prompting the need for a better solution.
• the invention provides a technique for transparently loading software in the background for cellular telecommunication networks.
• the method comprises the steps of transmitting software data over a digital transmission link to designated devices in a base station.
• Each device includes a run-time memory, a backup memory, and a device processor.
• Data is written to the backup memory in the background while the associated device may be in service.
• the newly loaded data is copied from the backup memory to run-time memory when the device is idle.
• the processor switches device operations to run from backup memory when the device is idle.
• the switch enables the device to operate from the new software.
• a change in memory designation is also performed i.e. the backup memory becomes the current run-time memory and the previous run-time memory now becomes the current backup memory.
• a subsequent software load writes to the newly designated backup memory and an appropriate switch is again performed. Additional software loadings will continue to cycle in this fashion.
• a single memory bank comprising both run-time memory and backup memory is used in place of separate memory banks. The starting location for the backup memory is indicated by a pointer located sufficiently after the run-time memory.
• the software is written to the backup memory in the background to avoid interfering with possible device traffic.
• the processor switches code execution to the starting location for the backup memory.
• the device then operates from the new software and a switch in memory designation is performed.
• the data is written to the former run-time memory area in the background.
• An appropriate pointer switch is again made by the device processor. Additional loads repeat the load-and-pointer switch cycle as needed.
• the embodiments disclosed in the present invention provide a method of loading software that is efficient, economical, and transparent to the user.
• the method virtually eliminates down-time and revenue losses due to software loading for cellular operators.
• Figure 1 shows a prior art method of loading software in a cellular telecommunication system
• Figure 2 illustrates a method of background software loading in accordance with a first embodiment of the present invention
• Figure 3 illustrates a method of background software loading in accordance with a second embodiment of the present invention
• Figure 4 illustrates a method of background software loading in accordance with a third embodiment of the present invention.
• a mobile switching center In a basic cellular telecommunication system, a mobile switching center (MSC) is linked to a plurality of base stations by digital transmission links.
• the base stations are geographically dispersed to form an area of coverage for the system.
• Each base station (BS) is designated to cover a specified area or cell in which two way radio communication of voice or data can take place between a mobile station and the base station in the associated cell.
• the procedure for software loading is initiated at the MSC where the software data is distributed to the individual base stations.
• FIG. 2 illustrates a method of software loading in accordance with a first embodiment.
• An MSC 22 is coupled to a BS 24 by way of a Tl link 26.
• the device designated for software loading is selected by the MSC.
• the software data is then transmitted over the Tl link in timeslot 9 to BS 24 and routed to the designated device. Timeslot 9 of the Tl link specification is reserved for the transmission of control signals and is used for carrying software data during loading.
• timeslot 16 is used for such data transfer in the El link specification.
• other protocols may be used that designate software data to be transmitted in multiple timeslots for faster, more efficient loading.
• Components associated with each device in the base station include run-time memory (rtm) 27, backup memory (bpm) 28, and processor 30.
• the device runs from code stored in rtm 27 containing the current version of the operating software.
• the software loading process can be accomplished while the device is in operation, i.e. handling voice or data traffic. This occurs by writing the new software into to bpm 28 which is isolated from device operations. The action takes place in the background thereby permitting the device to be free from interruption during the load.
• Copying from bpm 28 to rtm 27 can be initiated by signaling from MSC 22 in order to make sure that the act does not interfere with ongoing traffic. Time critical tasks relating to handling traffic can be given higher priority by the MSC than those relating to software loading. Thus the MSC alerts the processor that the device is engaged and to delay copying the data to ensure traffic is maintained.
• Modifications to existing equipment may be necessary to allow operation in accordance with the present embodiment.
• the additional backup memory bank (bpm 28) may need to be added for each device and configured to receive transmitted software.
• Many existing devices contain processors that are used to block the device for software loading and maintenance etc. Modifications may be made to the part of resident software to allow the processor to manage the two memory banks.
• modifications to the operating software at the MSC can be made to implement the functionality for background software loading.
• FIG. 3 illustrates a technique for background software loading in accordance with a second embodiment of the present invention.
• the embodiment is a slight variation of that in embodiment one and includes essentially the same device components of rtm 27, bpm 28, and device processor 30' .
• MSC 22 transmits software data via Tl link 26 in timeslot 9 to bpm 28 of designated base station device 24' .
• software loading may proceed while the device is engaged in activity by writing the software data to bpm 28 in the background.
• Processor 30' manages the background activity and is alerted by MSC 22 when the device becomes idle. When an idle state is sensed, processor 30' has the possibility to immediately switch run-time operations from rtm 27 to bpm 28. That is, the bpm becomes the current rtm and vice versa such that ensuing device activities will operate from the new software.
• the MSC can direct the processors to delay until all devices have been updated before switching to the new software.
• the resident software for processor 30' includes a provision for keeping track of which memory bank contains the current rtm code. For existing devices, a relatively simple modification of the resident processor software is performed to include this functionality.
• a major advantage of the present embodiment is that, once the background software loading has been completed, the devices can switch to running the new software virtually instantaneously.
• FIG. 4 illustrates a technique for background software loading in accordance with a third embodiment of the present invention.
• MSC 22 transmits software data via Tl link 26 in timeslot 9 to bpm 28' of the base station device 24" .
• the embodiment includes a single memory 29 with sufficient capacity to contain both rtm 27' and bpm 28' having respective starting addresses Al and A2.
• Processor 30" directs the background loading to starting address A2 associated with bpm 28' .
• the device operates from the software stored in rtm 27' and is undisturbed during software loading to bpm 28' .
• processor 30" changes the pointer address from Al to A2 to enable execution of the newly loaded software.
• the present invention discloses a technique for conveniently loading software in the background that provides the capability to load, modify or replace software in cellular networks without interfering with active devices.
• the described method further provides an efficient and economical solution to software loading by eliminating costly down time.
• a further advantage is that no modifications to the standard method of software delivery are required since the standard Tl link continues to be used in the same way.
• CDMA Code Division Multiple Access
• GSM Global System for Mobile Communication
• PDC Personal Digital Cellular

Landscapes

• Engineering & Computer Science (AREA)
• Software Systems (AREA)
• General Engineering & Computer Science (AREA)
• Theoretical Computer Science (AREA)
• Computer Security & Cryptography (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Mobile Radio Communication Systems (AREA)
• Information Retrieval, Db Structures And Fs Structures Therefor (AREA)
• Techniques For Improving Reliability Of Storages (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (2)

Family

ID=25330819

Family Applications (1)

Country Status (8)

Cited By (10)

Families Citing this family (30)

Family Cites Families (31)

• 1997
  • 1997-05-20 US US08/859,395 patent/US6324411B1/en not_active Expired - Lifetime
• 1998
  • 1998-05-15 CA CA002290404A patent/CA2290404A1/en not_active Abandoned
  • 1998-05-15 BR BR9808806-8A patent/BR9808806A/pt not_active Application Discontinuation
  • 1998-05-15 DE DE19882411.4T patent/DE19882411B3/de not_active Expired - Fee Related
  • 1998-05-15 CN CNB988069822A patent/CN1179595C/zh not_active Expired - Fee Related
  • 1998-05-15 AU AU75610/98A patent/AU749010B2/en not_active Ceased
  • 1998-05-15 JP JP55028998A patent/JP2002502564A/ja active Pending
  • 1998-05-15 WO PCT/SE1998/000917 patent/WO1998053619A2/en not_active Ceased

Also Published As

Similar Documents

Legal Events