DE10150847B4 - Simple and secure method for determining the time zone of an Internet client - Google Patents

Abstract

Data communication system (1) having at least one central computer (2) and a computer time counter (10) which provides computer time counting data related to a reference time zone (B) and at least one client (3a) and a client Time counter (9a) providing client time count data related to the reference time zone (B) or another time zone (A), characterized
In that for determining the correctness of the client time count data and / or of client time zone data, the client time count data and the computer time count data are compared with one another and
- That during the time count data comparison, a modulo operation is performed with the client time count data and / or the computer time count data, or data derived therefrom.

Description

The The invention relates to a data communication system according to the preamble of claim 1, and a central computer for use in such a data communication system.

Of Furthermore, the invention relates to a data communication method according to the generic term of claim 17.

The Data transfer via the Internet continues to increase in importance. This communicates z. B. a central computer or central computer (server computer) with z. B. a remote therefrom arranged client, z. A stationary or portable computer, a mobile phone, etc.

The Communication takes place using so-called Internet protocols, in particular the Transmission Control Protocol (TCP) and the Internet Protocol (IP), TCP / IP for short.

For this is z. B. on the client (browser) software loaded, the TCP / IP protocol can understand and evaluate (socket or TCP / IP stack).

Of the The Internet's fastest growing service relies on hypertext Transfer Protocol (HTTP) and is called the World Wide Web (WWW). About the World Wide Web can individual documents, so-called websites or web pages.

HTTP is a client-server protocol. Before making an internet connection between the client and the server machine, the client can be specific Applications z. B. first with another web host assigned to him by an internet service provider (ISP). On this runs one of the client software (i.e., the browser) server software corresponding to the client.

Then becomes the client on the respective desired website on the server computer belonging Web address, which is then assigned by the client ISP web host is established from an internet connection.

The Web address is assigned in the form of one of the respective website URL (Universal Resource Locator). These is made up of several parts. The first part refers to that Internet Protocol (string "http: //") followed by - optionally - the string "www" as a label for the World Wide Web.

Of the next Part of the URL identifies the respective server computer, on which the website is stored (so-called domain name), and the Subsequent partial available - the Path to a local directory where the website is located on the server machine is stored. The last URL address part can then be the exact one Filename of the website, then from the server computer - under Interconnection of the ISP web host - via the Internet transferred to the client becomes.

Instead of to access simple files, over the Internet z. Belly programs stored in a corresponding directory (e.g., "cgi-bin") of the server computer to be started. Such programs may be e.g. to act on CGI programs (CGI = Common Gateway Interface). The last part of the URL indicates then the respective program file (e.g., "action.cgi").

With Help of a CGI program is e.g. possible between the client and a memory device associated with the server computer stored database information exchange (or general any, z. On appropriate data carriers, e.g. a hard disk, saved data).

To the start of the CGI program takes this connection with the database on, and asks the appropriate data.

These can in many different formats (e.g., text, graphics, Sound and video data, URLs, etc.).

The Data is formatted by the CGI program, for example put into HTML format or a DHTML format, or any other HTML derivatives (HTML = Hypertext Markup Language; DHTML = Dynamic Hypertext Markup Language), and then z. B. in the form of a HTML or DHTML website about transfer the internet to the client.

The respective website is then viewed by the browser on the client's screen displayed.

to Creation of CGI programs can be a Variety of different programming languages are used, for. Perl, C, C ++, Visual Basic, Fortran, etc. For programming languages such as B. C must the appropriate program code before it can be used with Help of a compiler to be compiled.

The compiler translates the program into machine code. Other programming languages - so-called script languages - do not need to be compiled. They will be executed during the term. Usually he becomes CGI scripts using Perl programming language.

Out US Pat. No. 6,094,672 discloses a method and an associated computer network for Management of time synchronization services known in the standardized Management logs interact with a time synchronization database which accesses time synchronization service modules. to Synchronization of the system time within the described computer network become by means of so-called "time source" computer units Time data to so-called "time client "transfer computer units, which their local time data with the transmitted synchronous time data synchronize. Here, the individual provided in the computer network Computer unit both as a time data transmitting "time source" computer unit as well as time data receiving "time client" computer unit act.

Out US Patent 5,938,729 is a method and associated computer system for monitoring the server services by means of a client computer known by means of a time indicator, each within the computer system generated message is timestamped at the time of sending the message. Here are the in the time zones used in the respective time zone independently of the time indicators of other local computers. In particular, be here the time counting data of a client computer compared to the time counting data of a server computer and in case of deviation of a maximum predetermined difference of the transmitted time indicator updated.

The Invention has for its object, a novel data communication system, a novel central computer for use in such Data communication system, as well as a novel data communication method available too put.

she achieves this and other goals through the objects of claims 1, 16 and 17.

advantageous Further developments of the invention are specified in the subclaims.

According to one The basic idea of the invention is a data communication system with at least one central computer and a computer time counter which provides computer time count data which to a reference time zone and at least one client and a client time counter, which provides client time count data which refer to the reference time zone or another time zone wherein, to determine the correctness of the client time count data the client time count data and the calculator time count data compared to each other and for Zeitzdatendaten comparison a modulo operation with the client time count data and / or the computer time counting data or derived data.

Thereby can e.g. be achieved that corresponding from the central computer, (e.g., transmitted from the above-mentioned client) Payload data with reference to the correct (or possibly corrected) Time can be stored, processed or output.

This is particularly advantageous if the corresponding payload e.g. shared by one or more users from multiple clients usable timemanagement system can be used. The time management system can e.g. a multi-user calendar or multi-user schedule function have, and z. B, centrally managed by the central computer.

Especially advantageous is an embodiment in which the central computer and the client over communicate the internet.

Prefers is the time counting data comparison the Difference between client time count data and computer time counting data, or from data derived from it.

Of the Client can e.g. a computer, in particular a portable or stationary computer be, or e.g. a telephone, in particular a portable or stationary telephone.

Advantageous become the time count data comparison the client time count data to the central computer, or to another, performing the comparison Transfer computer, especially about the Internet.

in the The following is the invention with reference to several embodiments and the attached drawing explained in more detail. In the drawing shows:

1 a schematic representation of a data communication system according to an embodiment of the invention;

2 a schematic representation of the time zones in which the in 1 shown server computer, as well as in 1 are shown clients; and

3 a schematic representation of the im Server computer calculated difference between server and client time.

In 1 is a schematic representation of a data communication system 1 shown according to an embodiment of the invention.

The data communication system 1 has a central computer 2 (Server computer), which is connected to the Internet (or alternatively to an intranet).

In an alternative, not shown embodiment, instead of the individual, central computer 2 Several central and / or distributed computers are used, which share the same functionality as the central computer 2 fulfill.

A first client 3a can via a calculator 4a an ISP (ISP = Internet Service Provider) - or in an alternative embodiment directly via a leased line - be connected to the Internet.

In a similar way is a second client 3b (and a variety of other clients) via another ISP computer 4b (or via other, not shown ISP computer) - or alternatively directly - connected to the Internet.

At the clients 3a . 3b These can be, for example, stationary or portable computers (eg personal computers, laptops or PDAs (PDA = Personal Digital Assistant)) or, for example, mobile phones.

The central computer 2 has a memory device 5 For example, one or more hard disks on which one or more databases are stored.

Furthermore, the central computer contains 2 a time counter 10 , eg a clock.

As in 1 as shown, each client rejects 3a . 3b an output device 6a . 6b , eg a screen or a display, as well as an input device 7a . 7b For example, a mouse and / or a keyboard.

Furthermore, each client 3a . 3b one or more storage devices 8a . 8b , For example, a hard disk, a memory chip (eg, a CMOS memory chip), etc. provided, and each time counter 9a . 9b , eg a clock.

As in 2 is shown, are the central computer 2 , as well as the clients 3a . 3b each at different locations on the globe 11 , which are each assigned to different time zones A, C, D. For example, there is the central computer 2 in Munich (Germany), the first client 3a in New York (USA), and the second client 3b in Tokyo (Japan).

The time in D (Tokyo) time zone is compared to that in a reference time zone B applicable time (here: GMT time (GMT = Greenwich Mean Time)) by +9 hours ahead, and those in the Time zone C (Munich) applicable time at +1 hour.

The time in A (New York) time zone is compared to the GMT time zone B valid time -5 Hours afterwards.

at other time zones, not shown, the difference between time and the time in GMT time zone B is also an integer Multiples of 0.5 hours. For example, can be in the appropriate Time zone applicable time the time applicable in GMT time zone B by x, 5 hours or running after.

The time counters 9a . 9b . 10 counts the time elapsed since a predetermined reference time, eg the seconds since January 1, 1970.

Alternatively, for example, the server time counter 10 do not count the time itself but, for example, receive the corresponding time count data from an external time counter in the manner of a radio clock.

The time counter 9a the first client 3a is - eg by a user of the client 3a , or in advance - has been set to count the time in that time zone in which the first client 3a is (local client time), and / or alternatively in the reference time zone (here: the GMT time zone B) applicable time (client GMT).

The time counter counts accordingly 9b the second client 3b (based on a setting made by a user) the time in time zone D (ie the time of the time zone in which the second client 3b is (local client time)), and / or alternatively in the reference time zone (here: the GMT time zone B) applicable time (client GMT).

The time counters 9a . 9b For example, they are often set inaccurately - for example, by a few minutes - (and / or there is no accidental or wrong time counter setting). In addition, the time counting of the time counters 9a . 9b be subject to an inaccuracy, so that the time counted by them - especially after prolonged operation - may differ from the actual time.

Furthermore, in the or one of the storage devices 8a . 8b (eg in a corresponding (CMOS) memory chip) of the respective client 3a . 3b an identifier (eg a time zone index) to be stored, which indicates the respective time zone A, B, C, D, in which the respective client 3a . 3b located.

The time zone identifier is used by the respective client user, for example when commissioning the client 3a . 3b (eg during (CMOS-) setup) with the help of the respective input device 7a . 7b in the client 3a . 3b entered, and then saved. Frequently, at the same time, the time counting device is also used 9a . 4b set.

For example, by the respective client 3a . 3b - after entering the time zone identifier, and the local client time - the client GMT will be calculated, and henceforth from the client 3a . 3b be used as "reference time" (see below).

The time counter 10 of the central computer 2 has been set - eg, by a computer user or administrator - or in advance - to count the time in the GMT reference time zone (server GMT), or alternatively the time in any other reference time zone.

In the database of the central computer 2 become the respective ones (eg from the Clients 3a . 3b transmitted or, for example, from the central computer 2 calculated) data, if necessary, each with respect to that of the time counter 10 determined GMT time (server GMT), and / or the respective client 3a . 3b transmitted GMT time (client GMT) and / or the local client time stored, alternatively in each case additionally with respect to each of the client 3a . 3b transmitted time zone identifier A, B, C, D.

The central computer 2 , or one in its memory device 5 stored program file is assigned to a specific URL address. This is made up of several parts.

Of the first part denotes the Internet Protocol (string "http: //"). This is followed by e.g. the string "www" as name for the World Wide Web. The next Part of the URL is the central computer on which the program file is stored (so-called domain name (e.g., "heptner.jp"), and the following Part the path to a local directory where the o.g. Program file (and optionally further program files) on the central computer is stored (e.g., "cgi-bin"). The last URL address part identifies the name of the respective program file (e.g., "action .cgi").

The program file may contain eg a CGI program (CGI = Common Gateway Interface). With the help of a CGI program it is possible, for example, to transfer data between the respective client 3a . 3b and on the storage device 5 of the central computer 2 to exchange stored database.

To start the CGI program, for example, at the input device 7a . 7b of the respective client 3a . 3b the corresponding URL address will be entered. In response to this - if not already done in advance - in a known per se with the interposition of the ISP computer 4a . 4b an internet connection between the respective client 3a . 3b , and the central computer 2 built up.

thereupon will that in the o.g. Program file stored CGI program started.

To the start of the CGI program takes this connection with the database on, and asks the appropriate data. These can be in many different formats (e.g., text, graphics, sound). and video data, etc.).

The data is formatted by the CGI program, for example, in HTML format or a DHTML format, or other HTML derivative format (DHTML = Dynamic Hypertext Markup Language), and then, for example, in Form of an HTML or DHTML website over the Internet to the respective client 3a . 3b transfer.

The corresponding HTMl or DHTML page is then controlled under the control of one or more storage devices 8a . 8b of the respective client 3a . 3b stored browser software program at the respective client output device 6a . 6b output or displayed.

For example, such an HTML or DHTML page can also be a start or login page which has one or more input fields into which the respective user of the client 3a . 3b by corresponding actuation of the input device 7a . 7b can enter certain data (eg a user ID and / or a (user-specific) password). This data can be used, for example, to the central computer 2 to carry out a check whether the respective user of the client 3a . 3b to access the central computer 2 in particular for reading or changing in its memory device 5 , eg the database data stored above is authorized.

Furthermore, the HTML or DHTML page contains a program code (eg a Java script), which when calling the page via the Internet from the central computer 2 to the respective client 3a . 3b and then executed by the respective browser software program - advantageous only when the login mask is pressed, so that the time difference between the corresponding client and server times is as small as possible.

The (Java Script / Perl Script) program reads from the respective time counter 9a . 9b delivered time count data (eg, the client GMT, and / or the local client time), and alternatively also the above-mentioned time zone identifier A, B, C, D (eg from one of the above-mentioned client memory devices 8a . 8b ).

Then - after appropriate input by the user - by the (Java Script / Perl script) program causes the corresponding data - along with the above, entered by the user data (eg the user ID) - over the Internet the central computer 2 be transmitted.

The received data (or a portion of the received data, such as the Client GMT and / or local client time and / or client time zone) passed to the CGI program.

The CGI program then reads the from the server time counter 10 supplied time count data (eg the server GMT), and compares these - possibly after previous conversion (see below) - with those of the client 3a . 3b received time count data (eg, the client GMT and / or the local client time). For this purpose, the corresponding time counting data (eg the server and the client GMT or the local client time) are deducted from each other.

In 3 schematically shows the difference d determined by the CGI program between the corresponding server and client time (here: in minutes). If the local client time is used instead of the client GMT, if minutes are used as a unit of time, the modulo 60 value of the resulting difference d or the local client time can be formed before the final evaluation is previously converted into the corresponding client GMT (eg using the above-mentioned time zone identifier or the time zone index A, B, C, D).

If the difference d (or its modulo 60 value) is in a first range Q (eg, -5 minutes ≤ d ≤ +5 minutes (or modulo d ≤ 5 minutes), or, for example, -10 minutes ≤ d ≤ + 10 minutes (or modulo d ≤ 10 minutes), etc.), it is assumed that the respective client 3a . 3b transmitted time count data, ie the corresponding client time, and / or the transmitted time zone identifier A, B, C, D is correct.

The allowable tolerance (± 5 minutes, or ± 10 minutes) takes into account the differences between the respective client and server time used for the evaluation as a result of the Internet transport time and a small, still acceptable inaccurate setting of the respective client time counter 9a . 9b ,

If the difference d is in the above-mentioned first area Q, the CGI program causes a first of several further HTML or DHTML pages to be sent to the respective client via the Internet 3a . 3b and under control of the respective browser software program at the respective client output device 6a . 6b is output or displayed.

This contains a data field, with which the respective user from the central computer 2 the (as correctly determined) time counting data (eg the client GMT, and / or the local client time) and / or the time zone identifier are communicated and / or with their help the correctness of the time counting data and / or the time zones Identification A, B, C, D is displayed or confirmed, and / or with the help of which the respective user is informed that server and client GMT are identical or substantially identical.

If the difference d (or its modulo 60 value) lies in a wider range R (eg, d <-5 minutes or d> +5 minutes (or eg modulo d> 5 minutes), or eg d <-10 Minutes or d> + 10 minutes (or eg Modulo d> 10 minutes), etc.), it is assumed that the respective client 3a . 3b transmitted time count data, ie the corresponding client time, and / or the transmitted time zone identifier are incorrect (eg the client time counter 9a . 9b too inaccurate).

The CGI program then causes a second of the several additional HTML or DHTML pages to be sent to the respective client via the Internet 3a . 3b and under control of the respective browser software program at the respective client output device 6a . 6b is output or displayed.

This contains a data field, with which the respective user from the central computer 2 the (as determined wrong) time counting data (eg the client GMT, and / or the local client time) and / or the time zone identifier are communicated, and / or to indicate to the user that the client time and / or time zone identifier is false and / or to inform the user that server and client GMT are not identical (or not substantially) identical), and / or with the help of which the user is requested to check the client time and / or the time zone identifier.

The user can then optionally by appropriate inputs to the input device 7a . 7b correcting his client. The (corrected) time count data, as well as alternatively also the (corrected) time zone identifier are then re-sent to the central computer as shown above 2 transferred, and checked there.

In an alternative embodiment, a third case may additionally be distinguished: is the difference d (or its modulo 60 value) in a third range S (eg, -27 minutes ≦ d ≦ -33 minutes, or, for example, 27 minutes ≦ d ≤ 33 minutes (or 27 minutes <modulo d <33 minutes)), it is assumed that the respective client 3a . 3b transmitted time count data, ie the corresponding client time, and / or the transmitted time zone identifier are correct, in particular, that the client 3a . 3b is in a time zone that has a time that is five hours ahead of or behind the time in GMT time zone B

The permissible tolerance (here: ± 3 minutes, alternatively eg ± 5 minutes) takes into account the differences between the respective client and server time used for the evaluation as well as a small, still acceptable inaccurate setting of the respective client and server time. time counting 9a . 9b , The tolerance is smaller than the above tolerance used for the first case (eg ± 5 or eg ± 10 minutes).

If the difference d in the above-mentioned third area S, is caused by the CGI program that a third of the above several HTML or DHTML pages over the Internet to the respective client 3a . 3b and under control of the respective browser software program at the respective client output device 6a . 6b is output or displayed.

This contains a data field, with which the respective user from the central computer 2 the (as correctly determined) time counting data (eg the client GMT, and / or the local client time) and / or the time zone identifier are communicated and / or with their help the correctness of the time counting data and / or the time zones Identification A, B, C, D is displayed or confirmed, and / or with the help of which the respective user is informed that server and client GMT are identical or substantially identical.

Alternatively or additionally, the data field may also contain a (warning) note, with which the user is informed, for example, that it has been determined that the client 3a . 3b in a time zone in which there is a time that is five or five hours ahead or behind (and / or with which, in particular if not so), the user for verification, in front of the time in GMT time zone B the client time and / or the time zone identifier is requested).

Alternatively, in each case a confirmation / if necessary. Correction of the calculated time zone of the client 3a . 3b respectively.

With the above-mentioned procedure it can be ensured, for example, that on the central computer 2 the respective ones (eg from the clients 3a . 3b transmitted or, for example, from the central computer 2 calculated) data each with reference to correct - or corrected - time count data and / or time zone identifiers are stored or output.

This is particularly advantageous if the corresponding data eg from one of several users of multiple clients 3a . 3b from jointly usable, eg from the central computer 2 managed timemanagement system (eg a timemanagement system with multi-user calendar or multi-user schedule function).

1

Data communication system

2

centrally computer

3a

client

3b

client

4a

ISP computer

4b

ISP computer

5

memory device

6a

output device

6b

output device

7a

input device

7b

input device

8a

memory device

8b

memory device

9a

time counting

9b

time counting

10

time counting

11

globe

Claims (17)

Data communication system ( 1 ) with at least one central computer ( 2 ) and a computer time counter ( 10 ), what computer time provides count data related to a reference time zone (B) and with at least one client ( 3a ) and a client time counter ( 9a ) providing client time count data related to the reference time zone (B) or another time zone (A), characterized in that for determining the correctness of the client time count data and / or client time zone data the client time count data and the computer time count data are compared with each other, and - that during the time count data comparison, a modulo operation is performed on the client time count data and / or the computer time count data or data derived therefrom. Data communication system ( 1 ) according to claim 1, wherein the central computer ( 2 ) and the client ( 3a ) communicate over the Internet. Data communication system ( 1 ) according to claim 1 or 2, wherein in the time count data comparison the difference between client time count data and computer time count data, or from data derived therefrom is formed. Data communication system ( 1 ) according to claim 3, wherein the client time count data is determined to be correct if the amount of the difference is in a first, predetermined range (Q), in particular less than 15, 10 or 5 minutes. Data communication system ( 1 ) according to claim 3 or 4, wherein the client time count data are determined to be incorrect if the amount of the difference is in a second region (R) different from the first region (Q), in particular greater than 15, 10 or 5 Minutes. Data communication system ( 1 ) according to one of Claims 3 to 5, in which the client time count data are additionally determined to be correct if the magnitude of the difference lies in a third region (S) different from the first and second regions (Q, R), in particular larger than 25 or 27 minutes, but less than 35 or 33 minutes. Data communication system ( 1 ) according to one of claims 4 to 6, in which, when the amount of the difference lies in the first, predetermined range (Q), at an output device ( 6a ) of the client ( 3a ) a first of several different data sets, in particular a first of several different Internet pages is output. Data communication system ( 1 ) according to one of Claims 4 to 7, in which, when the amount of the difference lies in the second, predetermined range (R), at the output device ( 6a ) of the client ( 3a ), a second, from the first record different record is output, in particular a second, different from the first web page. Data communication system ( 1 ) according to one of claims 4 to 8, in which, when the amount of the difference lies in the third, predetermined range, at the output device ( 6a ) of the client ( 3a ) a third, from the first and second record different record is output, in particular also containing a warning record. Data communication system ( 1 ) according to one of the preceding claims, in which, for the time count data comparison, the client time count data is sent to the central computer ( 2 ) or to another computer performing the comparison. Data communication system ( 1 ) according to one of Claims 1 to 10, in which, for the time count data comparison, the computer time count data is sent to the client ( 3a ) or to another computer performing the comparison. Data communication system ( 1 ) according to one of the preceding claims, in which the further time zone (A) is the time zone in which the client ( 3a ) is arranged. Data communication system ( 1 ) according to one of the preceding claims, in which the reference time zone (A) is the time zone in which the central computer ( 2 ) or the GMT time zone. Data communication system ( 1 ) according to one of the preceding claims, in which the client ( 3a ) is a computer, in particular a portable or stationary computer. Data communication system ( 1 ) according to one of the preceding claims, in which the client ( 3a ) is a telephone, in particular a portable or stationary telephone. Central computer ( 2 ), which is designed and set up so that it can be used as a central computer ( 2 ) in a data communication system ( 1 ) according to any one of claims 1-15, and for determining the correctness of the client time counting data the client time count data and the computer time count data compares with each other and in the time count data comparison a modulo operation with the client time count data and / or the computer Time counter data or data derived therefrom. Data communication method in which at least one central computer ( 2 ) and a computer time counter ( 10 ), which provides computer time count data related to a reference time zone (B) and in which at least one client ( 3a ) and a client time counter ( 9a ), which provides client timing data related to the reference time zone (B), or another time zone (A), characterized in that the method comprises the steps of: determining the correctness of the client time count data Comparing the client time count data and the computer time count data; Performing the time count data comparison by means of a modulo operation with the client time count data and / or the computer time count data, or data derived therefrom.