U.S. patent application number 11/488924 was filed with the patent office on 2007-05-03 for method for amortizing authentication overhead.
This patent application is currently assigned to Xanboo, Inc.. Invention is credited to Jack L. Chen, Babak Rezvani.
Application Number | 20070100772 11/488924 |
Document ID | / |
Family ID | 27398068 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070100772 |
Kind Code |
A1 |
Rezvani; Babak ; et
al. |
May 3, 2007 |
Method for amortizing authentication overhead
Abstract
A method is disclosed for amortizing the authentication overhead
of data transmissions. The method comprises establishing a first
secure transmission of data between a transmitter and a receiver by
transmitting at least one token to the receiver during the first
secure transmission. There may be any number of senders and
receivers, and any receivers may be a sender and vice versa. The
method also comprises establishing at least one additional
transmission of data between the sender and the receiver and
transmitting the data and at least one token during the at least
one additional transmission. In addition, the method compares the
at least one token transmitted during the at least one additional
transmission to the token transmitted during the first secure
transmission to guarantee the authenticity of that at least one
additional transmission. The method may also include transmitting a
preselected number of tokens during the first secure transmission.
The number of additional transmissions may or may not correspond to
the preselected number of tokens. The at least one additional
transmission may be conducted over an unsecure connection using
open communication. The first secure transmission may be protected
or encrypted.
Inventors: |
Rezvani; Babak; (Ossling,
NY) ; Chen; Jack L.; (Astoria, NY) |
Correspondence
Address: |
POLLACK, P.C.
THE CHRYSLER BUILDING
132 EAST 43RD STREET, SUITE 760
NEW YORK
NY
10017
US
|
Assignee: |
Xanboo, Inc.
|
Family ID: |
27398068 |
Appl. No.: |
11/488924 |
Filed: |
July 17, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09684012 |
Oct 6, 2000 |
7080046 |
|
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11488924 |
Jul 17, 2006 |
|
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|
60230319 |
Sep 6, 2000 |
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60230301 |
Sep 6, 2000 |
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Current U.S.
Class: |
705/67 |
Current CPC
Class: |
G06Q 30/0601 20130101;
G06Q 20/382 20130101; H04L 41/00 20130101; H04L 63/123 20130101;
G06Q 20/3674 20130101; G06F 21/31 20130101; H04L 63/08 20130101;
H04L 63/18 20130101 |
Class at
Publication: |
705/067 |
International
Class: |
G06Q 99/00 20060101
G06Q099/00; H04L 9/00 20060101 H04L009/00 |
Claims
1. A method for authenticating transferred data between a sender
system and a receiver system over an open network comprising the
steps of: establishing a first secure transmission of data between
the sender system and the receiver system; assigning a value to a
variable N where the value of N is a positive number and defines a
selected number of additional transmissions; transmitting selected
authentication information including N number of token(s) from the
sender system to the receiver system during the first secure
transmission so as to allow the sender system to authenticate
itself, each of the N number of token(s) being a unique identifier;
transmitting an acknowledgment from the receiver system to the
sender system, upon successful receipt and processing of the first
transmission by the receiver system; establishing at least one
additional transmission of data between the sender system and the
receiver system; transmitting the data and the N token(s) from the
sender system during the at least one additional transmission;
comparing the one token transmitted from the sender system during
the additional transmission to each of the token(s) transmitted
from the sender system during the one or more previous
transmission(s) to determine whether the most recent additional
transmission is authentic; establishing a second secure
transmission between the sender system and the receiver system;
assigning a second value to the variable N where the second value
of N is a positive number and defines a second selected number of
additional transmissions; and transmitting the second value of N
and a second value of N number of tokens to be used to authenticate
the sender computer, from the sender computer to the receiver
computer, each of the second N number of tokens being a unique
identifier.
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Description
FIELD OF THE INVENTION
[0001] The invention relates generally to network security and,
more particularly, to the field of authentication
BACKGROUND OF THE INVENTION
[0002] There are two major areas of the art of networking security,
encryption and authentication. Encryption is a method of hiding or
encrypting the data in transmission so that only the recipient may
have access to the data in its unhidden or unencrypted form. This
is also known as data privacy. Authentication on the other hand is
a method of ensuring that a transmission that is sent from a sender
to a receiver in fact came from the true sender. This is otherwise
known as integrity. A method that provides encryption ensures that
only the appropriate and intended receiver may possess the method
to decrypt the data for use, and a method that provides
authentication ensures that only an appropriate and valid sender of
a transmission did indeed sign the message with a uniquely
identifiable and verifiable signing method.
[0003] The area of security that the present invention is concerned
with is authentication. There are two major groupings of
authentication methods in use today, public key and private key
methods. In private key authentication, the method employs a
secret, shared key which is known only to the sender and the
receiver. In providing key authentication, a data transmission is
uniquely manipulated by use of an algorithm using the private key
before being sent to the receiver. A receiver, receiving such a
manipulated transmission, uses a reciprocal algorithm to the
sender's algorithm and the sender's private key to uniquely read
the message. Since only the sender and the receiver know the secret
key, only the sender could have manipulated the message so that the
receiver could read it.
[0004] The problem with private key authentication is the transfer
of the sender's secret or private key to the receiver. In addition,
secret keys in private key authentication are often breakable given
the amount of computing power available today, and are difficult to
maintain. In addition, the lifespan of the key is relatively short
due to the inherent breakability and difficulty in securely
transmitting the private key over an unsecure network. Typically,
private key authentication is used when there is an out of band
channel available to send private keys outside of the unsecure
network, such as a military installation with a dedicated, secret
radio key transmitter. Also, transmissions using private key
authentication are often small due to the necessary processing
overhead for each packet of the transmission; the larger the
packet, the larger the overhead needed to run the secret algorithms
on the data.
[0005] Public key authentication eliminates the secure key transfer
problem inherent with private key authentication. In public key
authentication, a pair of reciprocal keys is used between the
sender and receiver, the sender's private and public keys. The
unique property of public key authentication is that a message
received and verified with an algorithm using the sender's public
key could only have been signed using the sender's particular and
reciprocal private key of that pair.
[0006] Public key methods make use of the property that extremely
large numbers, the numbers used to manipulate the transmitted
messages, are extremely expensive to factor into smaller numbers
while the smaller numbers, which are the keys themselves, are very
easy to multiply together to get the large cipher number. In each
pair of keys used by the sender and the receiver, each of the
entities holds one and only one of the keys as well as the
multiplied large number. From this, it is easy to determine the
content of the message through a mathematical algorithm which does
not reveal the reciprocal key.
[0007] Because of these properties, many schemes, such as the
widely used SSL and HTTPS, employ public key schemes. However, the
expensive processing cost used in the algorithm needed to take the
extremely large cipher number and manipulate the data with it make
it very difficult for typical servers receiving appreciable traffic
to use because of the high per transaction authentication costs.
Unlike private key cryptography, there is no benefit for very small
transactions as small data sizes still take a significant initial
processing investment to get started. Therefore, the public key
schemes are suited for large transmissions with fewer transactions,
but unsuitable for the high frequency, smaller transactions
typically found on the Internet.
[0008] With both public and private key cryptography, processing is
done on a per-transmission basis, resulting in bloated processing
on the entity which is performing the authentication. With the
processing power available to malicious individuals spying on
network traffic, it is also impractical to vary the keys of the
private key method at a high enough frequency because of the
difficulty of sending the shared keys securely over an unsecure
network. The only way to reduce the processing overhead is to
reduce the authentication strength, to decrease the frequency of
key refreshes in private key methods, and to reduce the size and
strengths of the keys in public key authentication. This, of
course, is unacceptable for sensitive information such as credit
card information, stock trading activity, and voting which
frequently needs to be sent through unsecure networks.
[0009] Thus, there exists a need for efficiently authenticating
data from a user transmitting over an unsecure network that
requires both low processing overhead, yet still prevents a
third-party from impersonating the data from a legitimate user.
SUMMARY OF THE INVENTION
[0010] A method is disclosed for amortizing the authentication
overhead of data transmissions. The method comprises establishing a
first secure transmission of data between a transmitter and a
receiver by transmitting at least one token to the receiver during
the first secure transmission. There may be any number of senders
and receivers, and any receivers may be a sender and vice versa.
The method also comprises establishing at least one additional
transmission of data between the sender and the receiver and
transmitting the data and at least one token during the at least
one additional transmission. In addition, the method compares the
at least one token transmitted during the at least one additional
transmission to the token transmitted during the first secure
transmission to guarantee the authenticity of that at least one
additional transmission. The method may also include transmitting a
preselected number of tokens during the first secure transmission.
The number of additional transmissions may or may not correspond to
the preselected number of tokens. The at least one additional
transmission may be conducted over an unsecure connection using
open communication. The first secure transmission may be protected
or encrypted.
[0011] The method may also include transmitting a checksum value
during the first transmission and having a receiver verify that the
checksum value is accurate by comparing the transmitted value to a
checksum value generated using a similar checksum algorithm at the
receiver. A Checksum value may also be included during the at least
one additional transmissions. The generation of the checksum value
during the at least one additional transmissions may also depend on
data or checksum values from any or all previous and future
checksum values of other at least one additional transmissions or
the first secure transmission.
[0012] An adaptive scheme may be included that varies the number of
tokens and additional transmissions to vary the authentication
strength.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more complete understanding of this invention,
reference should now be made to the embodiments illustrated in
greater detail in the accompanying drawings and described
below.
In the drawings:
[0014] FIG. 1 is a schematic view of one embodiment of a client
server system in accordance with the present invention.
[0015] FIG. 2 is a schematic view of the client and server
components of the system shown in FIG. 1.
[0016] FIG. 3 is a schematic view of the controlled devices and
virtual representation of same in the server database of the system
shown in FIG. 1.
[0017] FIG. 4 is a schematic of a generic sender and receiver
system employing the authentication scheme of the present invention
using a secure transmission.
[0018] FIG. 5 is a generic sender and receiver system employing the
authentication scheme of the present invention using a less secure
or unsecure transmission of the present invention.
[0019] FIG. 6 is a flow chart showing the steps of performing the
method of the present invention.
[0020] FIG. 7 is a flow chart showing the sender performing its
portion of the method of the present invention.
[0021] FIG. 8 is a flow chart showing the receiver performing its
portion of the method of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Overview of System Architecture
Client-Side
[0022] In FIG. 1 there is shown a client and server system 10 in
accordance with the present invention. The client server system 10
includes a client 12 and a server 14 which are connected via a
global computer network 16, such as the Internet.
[0023] The client 12 is operated by a local user (not shown). The
client 12 may comprise a plurality of nodes, such as first user
node 18 and second user node 20. It should be understood that the
nodes 18 and 20 may be located at a single location, such as the
user's house or at separate locations such as the user's main house
and the user's vacation house. The present invention contemplates a
plurality of local user locations and/or a plurality of remote user
locations.
[0024] In one form of the invention, the user node 18 includes a
client computer 22 that is connected to the global computer network
16 via an Internet Service Provider (ISP) 23 by any conventional
means, such as a dial-up connection, DSL line, cable modem,
satellite connection, or T1 line. The client computer 22 includes
an Internet browser program 26 for accessing web pages via the
global computer network 16.
[0025] A monitoring module 28 is also provided which serves as a
gateway between the server 14 and at least one connected device 32.
The monitoring module can take various forms, such as a software
program 29 running on the client computer (as shown at node 18).
Alternately, the monitoring module 28 can take the form of a
stand-alone appliance 30 (as shown at node 20) which is connected
to the global computer network 16 and operates separately and
independently from the client computer 22. The monitoring module 28
is described in greater detail below.
[0026] At least one, and preferably a plurality of, device or
appliance 32 is connected to and controlled by each monitoring
module 28. The connection between the monitoring module 28 and the
various devices 32 can be wired or wireless.
[0027] The appliances 32 encompass a multitude of devices which are
capable of being controlled or mediated by an external controller.
Such appliances include camera 34, radio 36, smoke or fire detector
38, contact sensor 40, and light switch 41. Although not
illustrated, it should be understood that the present invention
encompasses many other such devices such as various audio input and
output devices, various visual displays, washers/dryers, microwave
ovens, cooking ranges, car alarms, plant watering devices,
sprinkler, thermostats, carbon monoxide sensors, humidistats, rain
gauges, video cassette recorders, radio tuners, and the like.
[0028] In addition, a myriad of notification devices, such as pager
42, can also be incorporated into the system. As best seen in FIG.
1, the pager 42 is in wireless communication with a wireless or
cellular transmitter 44 associated with the server component 14.
Other notification devices besides the pager 42 are also
contemplated by the present invention including, e-mail clients,
wireless hand-held computers, wireless wearable computer units,
automatic web notification via dynamic web content, telephone
clients, voice mail clients, cellular telephones, instant messaging
clients, and the like.
Server-Side
[0029] The server 14 of the present invention includes a web server
46 and a database server 48. The web server 46 generates static web
pages and dynamic web pages from data contained in the database
server 48. The web pages 50 can be viewed by the user on the
Internet browser 26 running on the client computer 22.
[0030] It is contemplated that the client 12 and the server 14
communicate over the global computer network 16 via the
conventionally available TCP/IP environment using the HTTP
protocol. Of course, it should be understood that any
request-response type of protocol and socket-based packet transport
environment would also be suitable and within the scope of the
contemplated invention.
[0031] It is also contemplated that the server 14 of the present
invention functions as the master controller of the system 10. In
addition, the client-server configuration of the system 10 and the
connection of the system 10 to the global computer network 16 via
an ISP 23 allow a user to access the system 10 via any computer,
monitoring appliance or similar device connected to the global
computer network 16.
[0032] In this way a user is able to control and monitor a
plurality of devices 32 connected to the monitoring module 29 at
node 18 and a plurality of devices 32 connected to the networked
monitoring module 30 at node 20. The devices 32 can be accessed via
any personal computer 22 by accessing the control server 14 via the
global computer network 16. By using a global computer network 16
it should be clear that a user, or anyone the user permits access
to, can readily monitor and control the monitoring modules 28 at
nodes 18 and 20, from any location, using any suitable device that
has access to the global computer network 16.
The Monitoring Module
[0033] Referring now to FIG. 2, the monitoring module 28 serves as
the connection hub for the controlled devices 32 and as the gateway
for brokering communications between the devices 32 and the control
server 14 via the global computer network 16.
[0034] One of the functions of the monitoring module 28 is to serve
as a translation and brokering agent between the server 14 and the
connected devices 32. In its software form 29, the monitoring
module 28 comprises a plurality of dynamically loaded objects, or
device descriptors 49 that allow the server 14 to interface with
the connected devices 32. The dynamically loaded device descriptors
49 act as the device drivers for the connected devices 32,
translating, in both directions, the monitoring, command, and
control data sent and received from the monitoring module 28 to the
server 14 via the global computer network 16. Each device
descriptor 49 also translates the signals received from the
monitoring module 28 into the specific electrical signals that are
required to communicate with, both input and output, and control
its associated device 32. In addition, because each device 32 has
its own specific interface and requires a specific set of
electrical signals to monitor and control it, a different device
descriptor 49 must be provided for each specific model of each
device 32.
[0035] The monitoring module 28 also controls the communication
between the server 14 and the connected devices 32 via the global
computer network 16. The HTTP protocol employed by the existing
global computer network is a stateless protocol. Since the
knowledge of the current state of the connected devices is vital to
the successful operation of the system 10, it is necessary for the
monitoring module 28 to store the persistent state of the connected
devices 32 and to provide a system for periodically updating and
obtaining the state of each connected device 32 and for obtaining
commands from the server 14. The monitoring module 28 does this by
polling 50 the server 14 and maintaining a system heartbeat 52.
[0036] The monitoring module 28 polls 50 by scheduling a
transmission between the monitoring module 28 and the server 14 in
which it checks for commands from the server 14. If commands are
waiting on the server 14, the server will return commands in an
algorithmic manner, that can take various forms, for processing and
also informs the monitoring module that N commands are waiting in
the queue. The monitoring module 14 will then poll the server 14
and retrieve data from the server 14 until there are no more
commands in the queue. In this way, commands from the server 14 can
be delivered to the monitoring module 28 to effect changes in the
devices 32 over the stateless medium of the existing global
computer network 16.
[0037] In a typical polling operation 50, the client computer 22
issues a command for incurring a change in state of one of the
control devices 32. The change in state command is posted to a data
store 51, such as a command queue associated with the server 14.
Similarly, if server 14 desires to make an internal change to
monitor 28, such as setting or modifying the polling 50 or
heartbeat 52 time intervals, these commands are likewise posted to
the storage device 51. Upon reaching the end of the current polling
interval, the monitoring module 28 sends a transmission to the
server 14, requesting any queued commands. The monitoring module 28
continues to poll, using a preselected transmission scheme, until
the queue of commands waiting for the monitor 28 is complete. Each
command received from the queue is acted upon when it is received
and any associated state changes are effected. The server 14
transmits an acknowledgment of receipt and successful processing of
the data back to the monitoring module 28.
[0038] The monitoring module 28 is also responsible for maintaining
a heartbeat 52 or a scheduled periodic update regime to refresh the
current state of the devices 32 stored in the database server 48.
The primary function of the heartbeat 52 is to synchronize the
states of the devices 32 and the virtual representation of those
devices stored on the server 14. The heartbeat 52 also functions to
send device events and state changes between the devices 32 and the
server 14 to effect this synchronization of the control server 14
and to assure that the monitoring module 28 and the server 14 are
synchronized.
[0039] Not only is the monitoring module able to send commands to
the server 14, but the server 14 is able to send commands back to
the monitoring module 28. The types of transmissions that cause the
server 14 to send unsolicited transmissions back to the monitoring
module 28 are to set or update the heartbeat or polling time and to
issue a command to update a component of a device.
[0040] In a typical heartbeat operation 52, the monitoring module
28 sends a transmission to the server 14 in response to a change in
state of a connected device 32, a synchronization of a control
device 32 with server 14, a triggered alert event, or the like. In
such a heartbeat operation 52, all data intended to be transmitted
to the server 14 is transmitted to the server 14 via the global
computer network. The server 14 transmits an acknowledgment of
receipt and successful processing of the data back to the
monitoring module 28.
[0041] Along with maintaining the polling and heartbeat operations
and sending and receiving events, data, and commands 54 to and from
the server 14, the monitoring module 28 also takes care of many
network level activities 56 such as verifying passwords, dialing up
the ISP if necessary, periodically uploading accounting/billing
information, and performing security measures.
[0042] Another function of the monitoring module 28 is the storage
of the persistent state of the devices 32. In the event that the
user's computer 22 crashes and the monitoring module 28 must be
restarted, many of the parameters that were negotiated between the
monitoring module 28 and the server 14 during the registration
process are stored in the memory of the monitoring module.
Device Interface and Descriptors
[0043] Referring now to FIG. 3, a series of devices 32, 32a, 32b,
32c, 32d is shown. Each device is connected to a monitoring module
28 via a device descriptor or driver 49 (only one shown). Each
device includes a customizable user interface 58 that is viewable
on the client computer 22 over the global computer network 16
through a virtual representation of the user interface stored on
the web server 46, as explained below. The user interface 58
comprises at least one resource or sub-devices 60, 62, and 64.
Typically, a resource provides a specific functionality of the
device. For example, the device shown in FIG. 3 represents a VCR
having a recording setting resource 60, a channel selecting
resource 62, and a power selecting resource 64. Of course, a
typical VCR would have many other operational resources, but the
resources illustrated are sufficient to describe the basic
operation of the device.
[0044] Each resource 60, 62, 64 is made up of components or the
basic building blocks of the user interface 58 of the device. For
example, the recording setting resource 60 comprises a display
component 70 and a series of pushbuttons 72, 74, 76, 78 which
activate the VCR's fast forward, reverse, play, and stop functions,
respectively. The channel selecting resource 62 comprises the
display component 70 and a pair of pushbuttons 82 which activate
the up channel and down channel functions of the VCR. The power
selecting resource 64 comprises a toggle switch 80 for activating
the VCR's power on and power off commands and an LED indicator 81
which indicates the power condition of the VCR.
[0045] A virtual representation of each device 32, 32a, 32b, 32c,
32d also exists as a record 94, 94a, 94b, 94c, 94d in the database
server 48 of the control server 14. Each record contains an entry
for each resource and its associated components which make up the
device. For example, The record 94 for the VCR device 32 contains
an entry 90, 91, 92 for each resource 60, 62, 64 and an entry 90a,
90b, 90c, 90d, 91a, 91b, 92a, 92b for each component 70, 72, 72,
74, 80, 81, 82, respectively. In addition, a web page 50 can be
generated by the web server 46 by extracting the associated record
for that device from the database server 48 and creating a
graphical, textual, tactile, aural, or other similar modality user
interface representation of that device which a user can access via
the Internet browser 26.
Basic Operation of the System
[0046] In operation, the client 12 first registers with the server
component 14 to begin using the services offered therein by
accessing the web server 46 of the server component 14 via the
client browser 26. At this point, an account is opened for the
client 12 and the user's information is stored in the database
server 48. If it has not been previously registered, the monitoring
modules 29 and 30 would also be registered with the server
component 14 and their information would also be stored in the
database server 48 and associated with the node 18. Once the
monitoring modules 29 and 30 have been registered, any device 32
that is attached to either of the monitoring devices 29 and 30
would also be registered in the system, stored in the database
server 48, and available to the user. Each device 32 communicates
with the monitoring modules 29, 30 and either exports its interface
to the database server 48 or otherwise obtains a default interface
configuration, as explained in greater detail below. These
interfaces, as described in greater detail below, are adapted to be
displayed, to be viewed, and to be interacted with by the user via
the client browser 26 over the global computer network 16 by
accessing the web server 46.
[0047] A few uses of the present system 10 will now be explained to
aid in the understanding of the operation. For example, the contact
sensor 40 could be associated with the front door (not shown) at
the remote location 20 and set to trip whenever the front door is
opened. The camera 34 is also positioned to view the front door
location and can be programmed to take a digital photograph
whenever the sensor contact 40 is tripped and transmit that
photograph to be stored in the database server 48. When, in fact,
the contact sensor 40 detects that the front door has been opened,
an event notification or alarm trigger is transmitted by the
monitoring module 30 to the database server 48 which has been
previously programmed to transmit a notification event to the
user's pager via the cellular transmitter 44. As the contact sensor
is tripped, the camera 34 takes a picture of the front door and
transmits that picture via the monitoring module 30 via the global
computer network 16 to the database server 48. The user, having
been notified via the pager 42, can now access the web server 46 of
the server component 14 via his Internet browser 26 to retrieve the
photograph that has been stored on a database server 48. In this
way, the user can determine whether an intruder has entered via the
front door of his vacation home or whether his family has just
arrived for their vacation.
[0048] Another use for the system 10 would be for the user located
at the node 18 to be able to control his lamp 42 at his vacation
home located at node 20. The user would contact the web server 46
via his Internet browser 26 to access the database entry of the
light switch 41. A virtual representation of the light switch 41
would be available on the web server 46 and could be manipulated by
the user to remotely change the state of the light switch 41 and
the connected lamp 46, say from being "off" to being "on". To do
this, the user would simply manipulate the on/off virtual
representation of the light switch on the web server 46 and this
command would be placed in a queue of waiting commands on the
server component.
[0049] Periodically, the controlling module or monitor 30 polls the
server component 14 looking for waiting commands, such as the
change state command of the light switch 41. Thereafter, the
command would be transmitted to the monitoring device 30 which
would instruct the light switch to change from the "off" state to
"on" state, and, thus, turning on the lamp 46. This change in state
of the lamp 46 could be viewed by an appropriately positioned
camera, such as camera 34, which would be used to visually monitor
the remote location 20 to determine whether the command had been
completed successfully.
The Method and Svstem for Amortizing the Authentication
Overhead
[0050] Having described a complex preferred network system in FIGS.
1-3, FIGS. 4-8 describe a simplified preferred network system to
facilitate an understanding of the underlying concepts of the
present invention and the scope to which those concepts can be
extended.
[0051] Referring now to FIG. 4, in the present invention there are
two main entities, a sender 12 and a receiver 14 which communicate
over a global network 16, which is preferably a packet switched
network. The protocol disclosed is particularly advantageous in a
client server environment, although it may also be employed in any
peer to peer environment. It should also be apparent that the
system contemplates a plurality of senders 12 and/or a plurality of
receivers 14 which are in communication over various local and
global networks 16.
[0052] While in the current implementation the sender 12 is a
computer, it should be understood that the sender 12 can be any
entity which transmits data to a destination, including a receiver
which transmits data back to the sender. Other suitable senders may
include, but are not limited to, home appliances, cameras, home
gateways, and the like. Similarly, the receivers can be any entity
which is capable of receiving data, including clients that receive
return data transmissions from receivers. Suitable receivers
include, but are not limited to, database servers, web servers,
gateways, firewall servers, ISP gateways, network enabled cameras,
networked home appliances, and the like.
[0053] Many different types of networks which the senders 12 use to
communicate with the receivers are also contemplated by the present
invention 14. These networks may be of any size and may reach and
travel over a plurality of media, not limited to, wired and
wireless networks.
[0054] The present invention includes a sender computer 12
communicating over a global network 16, such as the Internet, to a
receiver computer 14. The present implementation also includes a
software program 120 running on the sender computer 12 which
packages and sends data to another program 122 running on the
receiver 14 via the global computer network 16. In the present
implementation, programs 120 and 122 are implemented in software;
however, the functionality of the software programs may also be
implemented in hardware, firmware, or the like.
[0055] In one preferred embodiment, the software program 120
running on the sender 12 can generate and transmit many different
data forms, types, and amounts over the network 16 and may be
processed by the software 122 running on the receiver 14. This data
may include, but is not limited to, large video streams,
acknowledgment messages, requests for data, email messages, and the
like. Also as part of the present invention, the software 120 is
used to perform client-side authentication of data transmissions
sent to the software 122 running on the receiver 14 and the
software 122 is used to process data from a plurality of the
senders 12, some of which may be correctly authenticating data and
some of which may not correctly authenticate the source of the
data. In addition, the present invention contemplates a number of
different protocols by which data is transmitted from the sender 12
to the receiver 14. The primary protocol used is HTTP, but other
suitable protocols include and are not limited to, TCP, IP, FTP,
UDP, HTTPS.
[0056] Having described the preferred embodiment of the present
invention in FIGS. 1-8, it should be apparent that the
sender/client 12 would typically have multiple transactions to
perform with the server 14 over the global computer network 16. The
nature of the data being sent from the sender/client computer 12 to
the receiver/server 14 must be absolutely verifiable that the data
indeed was from the sender/client computer 12 and not some other
source, such as a malicious third party or even a network
aberration. Since the global computer network 16 is an unsecure
network, the protocols used to transmit data from sender 12 to the
server 14 via the network 16 themselves provide no means for
authentication.
[0057] The data is transmitted over the network as a large number
of small transmissions, each requiring authentication. Since the
protocols in use, HTTP, TCP, UDP, and FTP are stateless, such that
information from one transmission is independent of other
transmissions and is discrete by transmission, authenticating a
previous transmission cannot aid in authenticating later
transmissions. Because the present invention requires
transmission-level authentication for a large number of
transmissions being sent on an unsecure network where illegitimate
data could be sent to receiver 14, it is clear that a light-weight,
transmission-level authentication scheme is necessary to guarantee
that the data sent from the sender 12 to the receiver 14 is indeed
legitimate data.
[0058] Using a private key scheme such as 3DES within a protocol,
such as HTTPS, attempts to guarantee authentication; only a
legitimate sender 12 with the secret, shared key can manipulate the
data such that the receiver 14 can reverse the data manipulation
algorithm and view the data. As the sender 12 increases the key
size to insure greater difficulty in compromising the key, the
processing power necessary to run the manipulation and reverse
manipulation algorithms increases on both the sender 12 and the
receiver 14. To combat this, the sender 12 might employ a large
enough key, but may refresh the secret key via a secure means, such
as SSL. Again, the increased frequency of key refreshes increases
the processing power needed for the private key methods both on the
sender 12 and the receiver 14, because secure transmissions, such
as SSL, are expensive themselves.
[0059] A public key scheme, as described in the background section,
is very expensive in terms of computer power for even very small
transmissions such as in the current system because of the initial
algorithm overhead each time it is used. Decreasing the key size
does decrease the computer power necessary, but it also cannot
provide a sufficient authentication level when decreased to a size
that reduces the computer processing load on the sender and
receiver to an acceptable level. To remedy the deficiencies in
private and public key schemes before-mentioned, the current system
employs a hybrid scheme which guarantees that third parties will
not be able to impersonate the sender 12 and that is capable of
authenticating transmissions while using a low amount of processing
power on both the sender 12 and receiver 14 to run the
algorithms.
[0060] The authentication method and system of the present
invention is illustrated in FIGS. 5-8, and uses the combination of
a secure connection for at least the initial transmission, such as
that afforded by SSL, and also a less secure token and an optional
checksum tracking system for subsequent transmissions. As shown in
FIGS. 4 and 6, the sender 12 sends a first transmission 100 to the
receiver 14 via the global computer network 16. This first
transmission 100 is conducted via a secure connection, such as that
afforded by SSL. For example, the sender 12 could connect to the
server using the HTTPS protocol, which uses as one of it's
negotiable algorithms, SSL.
[0061] In this first transaction 100, the sender 12 fully
authenticates itself, sending the necessary authentication
information to the receiver 14. Included in this first transmission
100, the client may also include N tokens 102. A token may be any
suitable unique identifier, such as a fixed data string or
number.
[0062] A checksum value 104 may also be sent to heighten the
security scheme in the first transmission 100. The tokens 102 and
the check sum 104 may be encrypted along with the rest of the first
transmission 100 or sent via an otherwise secure connection. In the
preferred embodiment, the packet for the first secure transaction
includes the source, address, destination address, N tokens, an
optional checksum seed, and the data payload.
[0063] If the first transmission 100 is successfully received and
processed, the receiver 14 sends its response 106 back to the
sender 12 as an acknowledgment.
[0064] The subsequent N transmissions are illustrated in FIGS. 5
and 6. The subsequent N transmissions can be preferably performed
over the global computer network in an unsecured or open
environment. For example, the subsequent transmissions can be sent
using any open communication, such as plain text. Of course, the
subsequent transmission may also be securely sent.
[0065] Not utilizing an authentication algorithm, except matching a
token against a set of tokens previously sent, means that the
processing overhead to verify these tokens is extremely low. During
each subsequent transmission 110, the sender 12 includes one of the
N tokens 112 along with whatever data 116 is being sent during
transmission 110 to the receiver 14. The receiver 14 checks the
token 112 against its list of N tokens previously sent to determine
whether the transaction is valid. In the preferred embodiment, the
packet for the subsequent transmission includes the source,
address, the destination address, token x, checksum y, and the data
payload.
[0066] In addition to the transmitted token 112, the client could
also send a new checksum value 114. This latest checksum value 114
would be used to further validate the current transaction. The
checksum procedure could be any conventional checksum procedure
wherein the algorithm can be only known by the sender and the
receiver and each checksum value transmitted between the sender and
the receiver is based on a previously generated checksum value or
based on a part or parts of a previous transmission or
transmissions. For example, the checksum algorithm may take the
current checksum value and add it to the checksum value generated
for the previous transmission. The resulting value, x, would be run
through any suitable algorithm such as, checksum=x.sup.2+x.sup.3.
This checksum value is transmitted to the receiver, whereupon it is
checked for accuracy.
[0067] In this way, a third party who snoops one of the tokens and
includes it in a later impersonated transaction would still fail in
the authentication procedure at receiver 14 since, unless the
snooper retained all sufficient previous transmissions and knew how
the checksums were secretly generated from the current transmission
and all sufficient previous transmissions, the checksum would be
incorrectly generated at the later transmission.
[0068] The effect of the present hybrid security scheme is that it
is no longer necessary to execute an expensive procedure to
authenticate every transmission except for the first transmission,
as it might be necessary in using currently available
authentication schemes. Thus, the processing power necessary to
effect authentication of the transmissions is reduced while also
reducing or eliminating a third party's ability to properly send
authenticated transmissions to the receiver 14.
[0069] The process of sending transmissions 110 with data 116 and
checksums 104 and one of the tokens 102 continues until the
receiver 14 receives a notification message 118, which can simply
be a new secure first transmission or an explicit end-of-round
message, that the current round of transmissions is over. Then, the
process is terminated. If the client 12 still needs to send
additional data to receiver 14, the process would be repeated
starting from sending the first transmission 100 until all the data
has been communicated between the sender 12 and the receiver
14.
[0070] By using the current hybrid system, the system is able to
dynamically throttle the processing overhead required to transmit
all the necessary data between the sender and the receiver while
eliminating the potential threat of a third party impersonator. For
example, if the threat of impersonation was low and it is desired
to maintain a low processor overhead, the value N and/or the number
of transmissions in a round of the algorithm could be set high to
reduce the number of times that the processing of secure first
transmission need take place. In contrast, the value of N and/or
the number of transmissions in one round of the algorithm could be
set lower when the threat of impersonation may be higher.
[0071] To give a further example, if it were determined that the
need for authentication was low when the client computer 12 was
sending a large quantity of data over the global computer network
16, such as when a publicly broadcast, large digital photograph or
streaming video was sent, the value of N could be set high.
Similarly, if the need for authentication was deemed to be higher,
such as when a credit card order was sent, the value of N and/or
the number of transmissions in a round of the algorithm could be
set lower. In this way, it is possible to finely tune the required
security for many different types of transmissions.
[0072] In another preferred embodiment of the present invention,
the value N and/or the number of transmissions in a round of the
algorithm is adaptively varied based upon a preselected set of
criteria, such as the client's usage patterns, the frequency of
transmission, and the like to vary the amount of processing
necessary per transmission.
[0073] In the present adaptive scheme, the number of tokens, N, is
set to a variable M. Each time that a first transmission is
performed, the client informs the server what the new value of M is
and includes M number of tokens to be used later to authenticate
the client. In addition, the server may instruct the client to
restart the transmission process with a new "first" secure
transmission based on the process or server requirements on its
end.
[0074] In determining and setting the value M, the clients and/or
server can take into account any combination of the following
criteria:
[0075] 1. The frequency of transmission from the client to server
as compared to an average frequency. The frequency is higher than
the average frequency, than the value M is set higher.
Alternatively, if the frequency is less than the average frequency,
than the value M could be set lower.
[0076] 2. The "closeness" of the client to the part of the web site
concerning a large number of transactions. For example, once a
client has logged into the system, and travels closer to the video
storage page by accessing introductory pages, the value M could be
decreased by the server in its anticipation of receiving large
number of transactions, such as a continually updated digital video
feed.
[0077] 3. Client usage patterns. For example, if a particular
client has logged in at noon consistently during the past week, it
is likely that this particular client will be logging on again
today at noon and transmitting data. In such an instance, the
variable M could be proactively increased at noon in anticipation
that it will again log on and transmit data. Similarly, if client
located on the east coast of the United States do not log onto the
server 14 during normal sleeping hours, i.e., between 12:00 a.m.
and 7:00 a.m., the variable M could be reduced since it is unlikely
that data will be sent by them during this time.
[0078] It should be understood that other quality of service issues
may be factored into the above-identified scheme to allow the
server to modify the value M. In addition, other criteria similar
to those set forth above, are contemplated and could be employed as
part of the present invention.
[0079] It is contemplated that all or some of the aforementioned
criteria will be used in any conventional algorithm, such as
statistical averaging scheme which accounts for each of the
criteria proportional to their importance and effect on the
processing overhead for authenticating the client. In this way, the
present invention can control the authentication strength
responsively and proactively, instead of being limited to
responding to only past conditions.
[0080] Some of the advantages inherent in such an adaptive scheme
include the following: the system can automatically adjust the
performance overhead as a response to monitored conditions instead
of requiring outside intervention to change the security strength
parameters; the algorithm can be used by clients of varying
processor power and varying network bandwidth connections to the
server without pre-defining parameters at the install time (this is
done by increasing the number of tokens when a set of transmission
is started, if the process or capability is low on the client); the
server and the client both can dictate the security processor
overhead in response to conditions that are occurring on their
respective ends; the power of the algorithm is increased as the
processing power necessary to process individual transmissions grow
smaller; and the larger the number of transmissions, the more
efficient the algorithm is.
[0081] A similar adaptive scheme is described in U.S. patent
application Ser. No. ______ entitled "Adaptively Controlled
Resource and Method for Controlling the Behavior of Same" filed on
______, 19______, the specification of which is incorporated by
reference herein in this entirety.
[0082] While certain preferred embodiments and various
modifications thereto have been described or suggested, other
changes in these preferred embodiments will occur to those of
ordinary skill in the art which do not depart from the broad
inventive concepts of the present invention. Accordingly, reference
should be made to the appended claims rather than the specific
embodiment of the foregoing specification to ascertain the full
scope of the present invention.
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