U.S. patent application number 16/152362 was filed with the patent office on 2019-02-07 for dead drop network architecture.
The applicant listed for this patent is LARC Networks, Inc.. Invention is credited to Michael R. Gray, Martin Kacin.
Application Number | 20190044796 16/152362 |
Document ID | / |
Family ID | 57144652 |
Filed Date | 2019-02-07 |
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United States Patent
Application |
20190044796 |
Kind Code |
A1 |
Kacin; Martin ; et
al. |
February 7, 2019 |
DEAD DROP NETWORK ARCHITECTURE
Abstract
A dead drop at a node in a dead drop (DD) domain performs
actions responsive to detecting events in the DD domain. The node
receives a notification request specifying an event to be
monitored, the notification request including a dead drop
identifier (DDID) referencing a storage location in the DD domain
associated with the specified event and a token associated with the
DDID. The node further specifies the action to perform in response
to detecting the occurrence of the specified event. The node
monitors for an occurrence of a specified event within the DD
domain. The node detects the occurrence of the specified event
within the DD domain. The node further performs a specified action
in response to detecting the occurrence of the specified event
within the DD domain.
Inventors: |
Kacin; Martin; (Los Altos
Hills, CA) ; Gray; Michael R.; (Dublin, OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LARC Networks, Inc. |
Los Altos |
CA |
US |
|
|
Family ID: |
57144652 |
Appl. No.: |
16/152362 |
Filed: |
October 4, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15640211 |
Jun 30, 2017 |
10116495 |
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16152362 |
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15136347 |
Apr 22, 2016 |
9729390 |
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15640211 |
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62151188 |
Apr 22, 2015 |
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62193927 |
Jul 17, 2015 |
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62193930 |
Jul 17, 2015 |
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62214124 |
Sep 3, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04L 63/126 20130101;
H04L 43/0876 20130101; H04L 63/10 20130101; H04L 67/1097 20130101;
H04L 63/0428 20130101; H04L 63/104 20130101; H04L 51/12 20130101;
G06F 21/6245 20130101; H04L 41/0681 20130101 |
International
Class: |
H04L 12/24 20060101
H04L012/24; H04L 29/06 20060101 H04L029/06; G06F 21/62 20130101
G06F021/62; H04L 12/26 20060101 H04L012/26 |
Claims
1. A method for exchanging data between a sender and a recipient
comprising: receiving, at a second node of a plurality of nodes of
a dead drop domain, from the sender via a first node of the
plurality of nodes of the dead drop domain, a write request to
write data to a specified dead drop of a plurality of dead drops in
the dead drop domain, wherein each dead drop of the plurality of
dead drops is a distinct storage location on a node of the
plurality of nodes and identified by a unique dead drop identifier
(DDID), each node of the plurality of nodes comprising a processor
and a memory and connected to one or more other nodes via a
network; determining that the specified dead drop is on the second
node; writing the data to the specified dead drop on the second
node; receiving a read request to read data from the specified dead
drop, the read request made by the recipient and received at the
second node from a third node of the plurality of nodes of the dead
drop domain; and providing the data from the specified dead drop to
the recipient in response to the read request.
2. The method of claim 1, further comprising: receiving, at the
second node, a create request from the recipient; creating the
specified dead drop at the second node in response to the create
request; generating a DDID identifying the specified dead drop, a
write token associated with the specified dead drop, and a read
token associated with the specified dead drop; and providing the
DDID identifying the specified dead drop, the write token, and the
read token to the recipient.
3. The method of claim 2, wherein writing the data to the specified
dead drop comprises: comparing a write token received from the
sender as part of the write request with the write token associated
with the specified dead drop; determining that the write token
received from the sender is valid based on the comparison; and
writing the data to the specified dead drop responsive to
determining that the write token from the sender is valid.
4. The method of claim 2, wherein providing the data from the
specified dead drop to the recipient comprises: comparing a read
token received from the recipient with the read token associated
with the specified dead drop; determining that the read token
received from the recipient is valid based on the comparison; and
providing the data from the specified dead drop to the recipient in
response to determining that the read token is valid.
5. The method of claim 2, wherein determining that the specified
dead drop is on the second node comprises: comparing a DDID
included in the write request with the DDID identifying the
specified dead drop; and determining that the specified dead drop
is on the second node based on the comparison.
6. The method of claim 1, further comprising: evaluating a
time-to-live (TTL) information for the specified dead drop at the
second node of the dead drop domain; determining whether a duration
for the specified dead drop indicated by the TTL information has
been reached; and deleting the specified dead drop from the second
node responsive to a determination that the duration for the dead
drop indicated by the TTL information has been reached.
7. The method of claim 1, further comprising: receiving, at the
second node of the dead drop domain, a notification request for the
specified dead drop; examining the notification request to identify
a type of event for which a notification is requested and a
notification address to which the notification is to be made; and
creating a trigger that causes the notification to be sent to the
notification address responsive to the identified type of event
occurring at the specified dead drop.
8. A system for exchanging data between a sender and a recipient
comprising: a processor for executing computer program
instructions; and a non-transitory computer-readable storage medium
storing computer program instructions executable by the processor
to perform operations comprising: receiving, at a second node of a
plurality of nodes of a dead drop domain, from the sender via a
first node of the plurality of nodes of the dead drop domain, a
write request to write data to a specified dead drop of a plurality
of dead drops in the dead drop domain, wherein each dead drop of
the plurality of dead drops is a distinct storage location on a
node of the plurality of nodes and identified by a unique dead drop
identifier (DDID), each node of the plurality of nodes comprising a
processor and a memory and connected to one or more other nodes via
a network; determining that the specified dead drop is on the
second node; writing the data to the specified dead drop on the
second node; receiving a read request to read data from the
specified dead drop, the read request made by the recipient and
received at the second node from a third node of the plurality of
nodes of the dead drop domain; and providing the data from the
specified dead drop to the recipient in response to the read
request.
9. The system of claim 8, the operations further comprising:
receiving, at the second node, a create request from the recipient;
creating the specified dead drop at the second node in response to
the create request; generating a DDID identifying the specified
dead drop, a write token associated with the specified dead drop,
and a read token associated with the specified dead drop; and
providing the DDID identifying the specified dead drop, the write
token, and the read token to the recipient.
10. The system of claim 9, wherein writing the data to the
specified dead drop comprises: comparing a write token received
from the sender as part of the write request with the write token
associated with the specified dead drop; determining that the write
token received from the sender is valid based on the comparison;
and writing the data to the specified dead drop responsive to
determining that the write token from the sender is valid.
11. The system of claim 9, wherein providing the data from the
specified dead drop to the recipient comprises: comparing a read
token received from the recipient with the read token associated
with the specified dead drop; determining that the read token
received from the recipient is valid based on the comparison; and
providing the data from the specified dead drop to the recipient in
response to determining that the read token is valid.
12. The system of claim 9, wherein determining that the specified
dead drop is on the second node comprises: comparing a DDID
included in the write request with the DDID identifying the
specified dead drop; and determining that the specified dead drop
is on the second node based on the comparison.
13. The system of claim 8, the operations further comprising:
evaluating a time-to-live (TTL) information for the specified dead
drop at the second node of the dead drop domain; determining
whether a duration for the specified dead drop indicated by the TTL
information has been reached; and deleting the specified dead drop
from the second node responsive to a determination that the
duration for the dead drop indicated by the TTL information has
been reached.
14. The system of claim 8, the operations further comprising:
receiving, at the second node of the dead drop domain, a
notification request for the specified dead drop; examining the
notification request to identify a type of event for which a
notification is requested and a notification address to which the
notification is to be made; and creating a trigger that causes the
notification to be sent to the notification address responsive to
the identified type of event occurring at the specified dead
drop.
15. A non-transitory computer-readable storage medium storing
computer program instructions executable by a processor to perform
operations for exchanging data between a sender and a recipient,
the operations comprising: receiving, at a second node of a
plurality of nodes of a dead drop domain, from the sender via a
first node of the plurality of nodes of the dead drop domain, a
write request to write data to a specified dead drop of a plurality
of dead drops in the dead drop domain, wherein each dead drop of
the plurality of dead drops is a distinct storage location on a
node of the plurality of nodes and identified by a unique dead drop
identifier (DDID), each node of the plurality of nodes comprising a
processor and a memory and connected to one or more other nodes via
a network; determining that the specified dead drop is on the
second node; writing the data to the specified dead drop on the
second node; receiving a read request to read data from the
specified dead drop, the read request made by the recipient and
received at the second node from a third node of the plurality of
nodes of the dead drop domain; and providing the data from the
specified dead drop to the recipient in response to the read
request.
16. The non-transitory computer-readable storage medium of claim
15, the operations further comprising: receiving, at the second
node, a create request from the recipient; creating the specified
dead drop at the second node in response to the create request;
generating a DDID identifying the specified dead drop, a write
token associated with the specified dead drop, and a read token
associated with the specified dead drop; and providing the DDID
identifying the specified dead drop, the write token, and the read
token to the recipient.
17. The non-transitory computer-readable storage medium of claim
16, the operations further comprising: comparing a write token
received from the sender as part of the write request with the
write token associated with the specified dead drop; determining
that the write token received from the sender is valid based on the
comparison; and writing the data to the specified dead drop
responsive to determining that the write token from the sender is
valid.
18. The non-transitory computer-readable storage medium of claim
16, wherein providing the data from the specified dead drop to the
recipient comprises: comparing a read token received from the
recipient with the read token associated with the specified dead
drop; determining that the read token received from the recipient
is valid based on the comparison; and providing the data from the
specified dead drop to the recipient in response to determining
that the read token is valid.
19. The non-transitory computer-readable storage medium of claim
16, wherein determining that the specified dead drop is on the
second node comprises: comparing a DDID included in the write
request with the DDID identifying the specified dead drop; and
determining that the specified dead drop is on the second node
based on the comparison.
20. The non-transitory computer-readable storage medium of claim
15, the operations further comprising: receiving, at the second
node of the dead drop domain, a notification request for the
specified dead drop; examining the notification request to identify
a type of event for which a notification is requested and a
notification address to which the notification is to be made; and
creating a trigger that causes the notification to be sent to the
notification address responsive to the identified type of event
occurring at the specified dead drop.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 15/640,211, filed on Jun. 30, 2017, which is a continuation of
U.S. application Ser. No. 15/136,347, filed on Apr. 22, 2016,
issued as U.S. Pat. No. 9,729,390, which claims the benefit of U.S.
Provisional Application No. 62/151,188, filed Apr. 22, 2015, U.S.
Provisional Application No. 62/193,927, filed Jul. 17, 2015, U.S.
Provisional Application No. 62/193,930, filed Jul. 17, 2015, and
U.S. Provisional Application No. 62/214,124, filed Sep. 3, 2015,
all of which are incorporated by reference herein.
BACKGROUND
1. Field of Art
[0002] The present invention generally relates to the field of
computer networking and data storage and in particular to a network
architecture for facilitating secure data exchange over a
decentralized computer network and data storage architecture.
2. Background of the Invention
[0003] The Internet (including the Web) enables users of computers
to quickly and easily exchange data. There is a wide range of
applications that leverage this ability to exchange data to achieve
powerful results for individuals and enterprises alike. Examples
include email, file sharing, home automation, entertainment, data
management, and more.
[0004] However, the way that data is exchanged over the Internet
makes the data, and those who send the data, vulnerable to
malicious actors. For instance, data moving between parties or
stored on a remote server typically include information associated
with the sender and the recipient. Accordingly, an interceptor of
the data may associate the data with the parties. If the data
contain sensitive information, it may leave the parties open to
identity theft or other malicious acts. As a result, many users are
discouraged from sharing important information via the Internet,
thereby missing out on many of the advantages that are afforded to
computer users.
SUMMARY OF THE INVENTION
[0005] According to embodiments of the invention, a method for
performing an action responsive to detecting an event in a dead
drop (DD) domain is described. The method includes monitoring, by a
node in the DD domain, for an occurrence of a specified event
within the DD domain. The method further includes detecting the
occurrence of the specified event within the DD domain. The method
further includes performing a specified action in response to
detecting the occurrence of the specified event within the DD
domain.
[0006] According to embodiments of the invention, a system for
exchanging data between a sender and a recipient is described. The
system includes a processor for executing computer program
instructions. The system also includes a non-transitory
computer-readable storage medium storing computer program
instructions executable by the processor to perform steps. The
steps include monitoring, by a node in the DD domain, for an
occurrence of a specified event within the DD domain. The steps
further include detecting the occurrence of the specified event
within the DD domain. The steps further include performing a
specified action in response to detecting the occurrence of the
specified event within the DD domain.
[0007] According to embodiments of the invention, a non-transitory
computer-readable storage medium storing computer program
instructions for exchanging data between a sender and a recipient.
The computer program instructions are executable to perform steps.
The steps include monitoring, by a node in the DD domain, for an
occurrence of a specified event within the DD domain. The steps
further include detecting the occurrence of the specified event
within the DD domain. The steps further include performing a
specified action in response to detecting the occurrence of the
specified event within the DD domain.
BRIEF DESCRIPTION OF DRAWINGS
[0008] FIG. 1 is a high-level block diagram illustrating an example
of passing data using a dead drop network architecture according to
one embodiment.
[0009] FIG. 2 is a high-level block diagram illustrating a detailed
view of the dead drop domain of FIG. 1 according to one
embodiment.
[0010] FIG. 3 is a high-level block diagram illustrating an example
of a dead drop storage node according to one embodiment.
[0011] FIG. 4 is a flowchart illustrating steps for using a dead
drop to pass data from a sender to a recipient according to one
embodiment.
[0012] FIG. 5 is a flowchart illustrating steps for using a DD to
monitor events and perform actions if an event is detected
according to one embodiment.
[0013] FIG. 6 is a high-level block diagram illustrating an example
of two nodes establishing a direct connection according to one
embodiment.
[0014] FIG. 7 is a high-level block diagram illustrating physical
components of a computer used as part or all of one or more of the
entities described herein in one embodiment.
DETAILED DESCRIPTION
[0015] The Figures (FIGS.) and the following description describe
certain embodiments by way of illustration only. One skilled in the
art will readily recognize from the following description that
alternative embodiments of the structures and methods illustrated
herein may be employed without departing from the principles
described herein. Reference will now be made to several
embodiments, examples of which are illustrated in the accompanying
figures.
[0016] It is noted that wherever practicable similar or like
reference numbers may be used in the figures and may indicate
similar or like functionality. This description occasionally uses
reference numbers in combination with letters to designate items
illustrated in the figures. Herein, a reference number used without
an accompanying letter (e.g., "150") references any or all
instances of the designated item, while a reference number used
with an accompanying letter (e.g., "150A") refers to the specific
item designated with that label in the figure.
[0017] FIG. 1 is a high-level block diagram illustrating an example
of passing data using a dead drop network architecture according to
one embodiment. FIG. 1 illustrates a recipient 110 in communication
with a sender 120 via a dead drop (DD) domain 130. FIG. 1 describes
a unidirectional data pass between a single sender 120 and a single
recipient 110. Embodiments can have multiple senders 120 and
recipients 110 engaged in bidirectional one-to-one and one-to-many
communications.
[0018] Briefly, the recipient 110 uses the DD domain 130 to
establish a communication channel that can be used to pass data to
the recipient. The recipient 110 provides the sender 120 with a
dead drop identifier (DDID) referencing a storage location within
the DD domain. The sender 120, in turn, uses the DDID to pass data
(e.g., send a message) to the recipient 110 via the DD domain 130.
The data transmission from the sender 120 to the recipient 110 is
secure in the sense that it is extremely difficult for a malicious
actor or other third party to locate, intercept, or decipher the
data. Thus, the DD network architecture is suited to communications
where security and privacy concerns are paramount. In addition, the
DD network architecture may be used to provide enhanced security
for general purpose communications.
[0019] In one embodiment, the recipient 110 includes software
executing on a computer used by a user (e.g., a person) to perform
tasks such as communicating with other users via the DD domain 130
or via other communication networks. For example, the recipient 110
may include software executing on a desktop, notebook, or tablet
computer, or another electronic device with computer functionality,
such as a mobile telephone, music player, television set-top-box,
home automation component, industrial equipment or connected
appliance. The recipient 110 may include an input device such as a
keyboard or touch-sensitive display that allows for the input of
data and an output device such as a display or speaker that allows
for the output of data. Functionality enabling the recipient 110 to
communicate via the DD domain 130 may be embedded into the hardware
of the recipient 110 and/or included in software executed by the
recipient 110.
[0020] Similarly, the sender 120 includes a computer used by a user
to perform tasks including communicating with other users via the
DD domain 130 or via other communication networks. The sender 120
may include the same components as the recipient 110. In fact, the
sender 120 may act as a recipient 110 and vice versa, depending
upon the direction of data flow in a given communication
transaction. The users who respectively use the recipient 110 and
sender 120 to communicate can be different people or the same
person.
[0021] The recipient 110 and sender 120 are connected to the DD
domain 130 via respective communications links 150A, 150B. The
communication links 150 may include network communication links
using conventional computer networking technologies. For example,
the communications links 150 may use wired or wireless network
communications technologies such as the wired and wireless forms of
Ethernet. Likewise, the communication links 150 may use other
communications technologies designed to support communication with
local peripherals, such as Universal Serial Bus (USB), Thunderbolt,
Bluetooth, Personal Area Network (PAN), Serial ATA, infrared, heat
signatures, and/or sound. The communications links 150 may be
encrypted using any encryption technologies such as secure sockets
layer (SSL), transport layer security (TLS), HTTP Secure (HTTPS),
virtual private networks (VPNs), Internet Protocol security
(IPsec), etc. In another embodiment, communication uses custom
and/or dedicated data communications technologies instead of, or in
addition to, the ones described above.
[0022] The DD domain 130 is a collection of one or more DD nodes
140 (labeled as nodes 140A-L in FIG. 1). ADD node 140 includes
functionality for acting in the DD domain 130 and a memory for
storing data within the domain. A typical DD domain 130 includes
many DD nodes 140. Each node 140 is connected to one or more other
nodes via DD communication links 160. The DD communication links
160 may use the same communication technologies as the
communication links 150 used by the recipient 110 and sender 120 to
connect to the DD domain 130. In one embodiment, the DD nodes 140
and DD communication links 160 are arranged within the DD domain
130 such that every node is reachable by every other node. In
another embodiment, the DD nodes 140 are logically or physically
partitioned so that some nodes cannot reach other nodes. The path
connecting two DD nodes 140 may pass through one or more
intermediate nodes. In addition, the recipient 150A and sender 150B
communication links respectively connect the recipient 110 and the
sender 120 to at least one DD node 140 within the DD domain 130.
The recipient 110 and sender 120 may also communicate with each
other using other communication links that do not pass through the
DD domain 130, such as a communications link 170.
[0023] To receive data using the DD domain 130, the recipient 110
sends a request to the DD domain 130 to create a DD on behalf of
the recipient. ADD node 140 within the domain 130 receives the
create request and either services the request or selects another
node to service the request. For example, the DD node 140 that
receives the request may randomly select another node within the DD
domain 130 and pass the request to the selected node. The random
selection may occur in a manner such that the node that receives
the request does not know which node ultimately services the
request.
[0024] The node 140 that services the request to create the DD
establishes a DDID that uniquely identifies the created DD. In
addition, the node 140 establishes a set of tokens associated with
the DDID. A token describes the access rights a possessor of the
token has with respect to the created DD. For example, an
embodiment includes a read token giving a possessor of the token
the right to read from the DD identified by the associated DDID and
a write token giving the right to write to the DD identified by the
associated DDID. The node 140 that services the request provides
the DDID and the associated tokens to the recipient 110.
[0025] The recipient 110 typically stores the DDID and associated
tokens in a secure manner. For example, the recipient 110 may store
the DDID and tokens in an encrypted data store at the recipient.
The recipient 110 provides the DDID and the write token to the
sender 120 via a communications link 170. This communications link
170 may be a secure or unsecure link, and may include communication
over the Internet and/or dedicated communications links. For
example, the recipient 110 may use encrypted or unencrypted email
to send the DDID and write token to the sender 120. Alternatively,
the recipient may use a different electronic communications
technique, such as short-range wireless communications, or even use
non-electronic techniques to exchange the information (e.g., a pen
and paper). In one embodiment, the DDID and one or more tokens are
combined and may be encrypted or encoded (e.g., by a hashing
function) to form a single code. In this embodiment, the recipient
110 may share the code with the sender 120 instead of sharing the
DDID and write token separately. The code may be decoded, for
example by the sender 120 or at a DD node 140, to determine the
DDID and token.
[0026] In addition, the recipient 110 and sender 120 may choose to
encrypt the data sent by the sender using one or more symmetric or
asymmetric encryption techniques. The recipient 110 and sender 120
may choose to exchange encryption keys, if necessary, at the same
time the recipient 110 provides the DDID and write token to the
sender 120. Alternatively, the recipient 110 and sender 120 may
exchange encryption keys at different times, may use encryption
techniques that do not require a key exchange, or may choose not to
encrypt the data. In one embodiment, the DD domain 130 itself is
used to perform the key exchange needed to facilitate an encrypted
communications link.
[0027] The sender 120 uses the DDID and associated write token to
send data to the recipient 110. In one embodiment, the sender 120
sends a write request to the DD domain 130 that includes the DDID
and the write token. In another embodiment, the write request
includes the DDID and data representing the write token. The data
representing the write token may be encrypted (e.g., by hashing,
obfuscation, etc.). This request is received by an initial DD node
140 in the DD domain 130. The receiving node 140 determines whether
it has the DD identified by the DDID. If not, the receiving node
140 sends a message containing the DDID and the write token to the
other nodes within DD domain 130. The node 140 storing the DD
associated with the DDID receives the message and verifies the
write token. If the token verifies, the node storing the DD creates
a connection with the receiving node, which in turn has a
connection with the sender 120. The sender 120 then writes the data
to the node storing the DD associated with the DDID.
[0028] Similarly, the recipient 110 uses the DDID and associated
read token to read data from the DD. In one embodiment, the
recipient 110 sends a read request to the DD domain 130 that
includes the DDID and the read token. In another embodiment, the
read request includes the DDID and data representing the read
token. The data representing the read token may be encrypted (e.g.,
by hashing, obfuscation, etc.). This request is received by an
initial DD node 140 in the DD domain 130. The receiving node 140
determines whether it has the DD identified by the DDID. If not,
the receiving node 140 broadcasts a message containing the DDID and
the read token the other nodes within the DD domain 130. The node
140 storing the DD associated with the DDID receives the message
and verifies the read token. If the token verifies, the node 140
storing the DD creates a connection with the receiving node, which
in turn has a connection with the recipient. The recipient 110 then
reads the data from the node storing the DD associated with the
DDID.
[0029] Thus, the DD network architecture described above permits
secure and private communications between the recipient 110 and the
sender 120. The sender 120, and/or other parties possessing the
DDID and write token can send data to the recipient. However, such
parties cannot read the data from the DD. Moreover, a malicious
actor who obtains access to one or more nodes 140 in the DD domain
130 may be able to obtain or read data stored in individual DDs.
But the malicious actor cannot determine the intended recipients of
the data because there is no mapping of DDIDs to recipients. For
the same reason, the malicious actor cannot determine the path
between a sender and a recipient. In addition, the data stored in
the DDs may be encrypted.
[0030] FIG. 2 is a high-level block diagram illustrating a detailed
view of the DD domain 130 of FIG. 1 according to one embodiment. As
described above, the domain 130 typically includes multiple DD
nodes 140 connected by DD communication links 160. The individual
nodes 140 within the DD domain 130 may be formed of physically
separate computers, such as a collection of geographically
disparate computers. In addition, some or all of the nodes may be
formed of virtual computers. For example, the nodes 140 of a domain
130 may be instances of virtual computers hosted in a cloud
environment.
[0031] Each DD node 140 has an associated set of characteristics
that describe attributes of the node. The characteristics may
describe the location of the node 140. The location may be
specified as a geographic location. In addition, the location may
be specified as a logical location (e.g., a "zone"). For example,
the logical location may indicate that the node is associated with
a particular enterprise (e.g., a business) or other group. The
characteristics may also describe physical properties of the node,
such as a node's processing power, storage capacity, uptime, and
the like.
[0032] In one embodiment, the set of DD nodes 140 in a DD domain
130 may be divided into multiple subdomains, with each subdomain
including a proper subset of nodes from the set of DD nodes in the
DD domain. The subdomains to which a node 140 is member may be
determined based on the characteristics of the node. For example,
the DD domain 130 may include nodes 140 distributed over a wide
geographic area (e.g., a country), and a subdomain may include
nodes physically located within a smaller area (e.g., a state
within the country). Similarly, the DD domain 130 may include nodes
140 associated with multiple enterprises, and a subdomain may
include only nodes associated with one of the enterprises or a part
of an enterprise.
[0033] In one embodiment, the DD nodes 140 are arranged as a mesh
network. Each node 140 is connected to at least one other node via
a DD communication link 160. Moreover, each node 140 maintains a
routing table identifying the nodes to which it is connected. A
node 140 can send a message to another node by forwarding the
message to the nodes to which it is connected. The nodes 140 that
receive the message in turn forward the message to other nodes,
until the message reaches the node to which it is directed. The
path followed by the message is formed of hops from node 140 to
node along the DD communication links 160.
[0034] Consider the communications between the sender 120 and the
recipient 110 described in FIG. 1 in the context of FIG. 2. As
shown in FIG. 2, the recipient 110 is connected to a node 140A of
the domain 130 via a communication link 150A. This node 140A serves
as the point of ingress to the domain 130 for the recipient. The
recipient 110 sends a request to the ingress node 140A of the
domain 130 to create a DD on behalf of the recipient. This request
may include domain information specifying a particular subdomain in
which the DD should be created. For example, the domain information
may specify that the DD should be created in a node 140 located in
a particular geographic area or managed by a particular
enterprise.
[0035] The node 140A serving as the point of ingress for the
recipient 110 receives the create request and analyzes the domain
information to identify the subdomain in which the DD should be
created. In one embodiment, the node 140A services the request by
randomly selecting a node within the specified subdomain that will
host the DD. In one embodiment, random selection is performed using
a load balancing technique, which may be performed by the node 140A
or by a separate computing device. In one embodiment, the node 140
services the request by randomly selecting a number of node hops
for which the request will be forwarded, and randomly selecting
another node within the specified subdomain to which the node 140A
is connected. The ingress node 140A then forwards the request to
the randomly selected node (e.g., node 140D) and also forwards the
selected value for the number of node hops. The node 140D to which
the request was forwarded randomly selects another node (e.g., node
140E) in the subdomain from its routing table, decrements the value
for the number of node hops, and forwards the request to the
selected node. This selection, decrement, and forward process
repeats until the value for the number of node hops reaches zero,
at which point the final node establishes and hosts the DD
associated with the request from the recipient 110. In one
embodiment, each node that forwards the create request includes the
path from the ingress node 150A to the forwarding node with the
request. The final node that creates the DD uses the path to
identify and contact the ingress node 140A for the recipient 110.
For example, the node 140 may use the path to send the DDID and
associated tokens to the ingress node 140A, so that the latter node
can provide this information to the recipient.
[0036] For example, assume the ingress node 140A receives a create
request from the recipient 110, and also assume that the request
specifies a subdomain encompassing nodes 140A, 140D and 140E, as
well as other nodes within the domain 130. Also assume the ingress
node 140A randomly selects "2" as the number of hops. The ingress
node randomly selects a node (e.g., node 140D) from the specified
subdomain in its routing table, decrements the hop value, and
forwards the request and decremented hop value (e.g., "1") to the
selected node. That node 140D, in turn, randomly selects another
node (e.g., node 140E), decrements the hop value, and forwards the
request and decremented hop value (e.g., "0") to the selected node.
The final node 140E evaluates the hop value and determines that it
is "0" and, therefore, creates the DD and associated tokens. The
final node 140E then returns the DDID and tokens to the ingress
node 140A via the reverse of the path used to reach the final
node.
[0037] Variations on the techniques described above may be used in
some embodiments. In one embodiment, a node forwarding a request
decrements the hop value only if the node is within the specified
subdomain. This variation may be used, for example, in situations
in which a node receiving a create request is not within the
specified subdomain and/or connected to any other nodes in the
subdomain. In this situation, the nodes may randomly forward the
request to other nodes until a node within the specified subdomain
receives the request, at which point the node in the subdomain
decrements the hop value and forwards the request anew if the hop
value is greater than zero or creates the DD and associated tokens
if the hop value is zero.
[0038] The sender 120, in turn, is connected to a different node
140L that serves as the point of ingress for the sender to the
domain 130 via a different communication link 150B. When the sender
120 makes a write request, the sender provides the DDID and write
token to the sender's ingress node 140L. This node 140L forwards
the request including the DDID and write token to the other nodes
in its routing table, and the other nodes continue to forward the
request until it reaches the node having the DD associated with the
DDID (e.g., node 140E). This node 140E verifies the token and
establishes a connection with the sender's ingress node 140L using
a return path created by the forwarding nodes. Alternatively, the
node 140E may establish a direct connection with the sender 120.
The sender 120 provides the data to be written to the ingress node
140L, and that node forwards the data to the node 140E having the
DD via the connection. A read request made by the recipient 110 is
handled in a similar fashion in one embodiment, except that the
recipient reads data from, rather than writes data to, the node
140E having the DD.
[0039] FIG. 3 is a high-level block diagram illustrating an example
of a DD node 140 according to one embodiment. The node 140 includes
a routing module 305, creation module 310, write module 315, read
module 320, time-to-live (TTL) module 325, data control module 330,
delete module 335, notification module 340, geo-fence module 345,
and data storage 390. Other embodiments may include different or
other modules in other embodiments. In addition, the behaviors of
the modules may differ in other embodiments.
[0040] The data storage 390 stores data used by the node 140. The
data may include data being maintained in DDs managed by the node
140, DDIDs and tokens associated with the DDs, and information used
by the modules within the node 140 to perform the tasks described
herein. Depending upon the embodiment, the data storage 390 may
include one or more types of non-transitory computer-readable
persistent storage media. For example, the data storage 390 may
include a hard drive, solid-state memory device, and/or other form
of persistent memory.
[0041] Turning now to the individual modules within the node 140,
the routing module 305 routes messages received by node 140. As
part of this task, an embodiment of the routing module 305
maintains the routing table for the node 140. The routing module
305 periodically communicates with other nodes 140 to which it is
connected to ascertain information about those nodes. This
information may include, for example, network addresses of the
nodes, information about the subdomains with which the nodes 140
are associated, and the like. The routing module 305 stores this
information about the connected nodes in the routing table. In
addition, the routing module 305 responds to routing table-related
communications from routing modules 305 of other nodes 140.
[0042] The messages handled by the routing module 305 include
messages related to create requests, write requests, read requests,
and other types of messages and requests described herein. For a
given message, the routing module 305 analyzes the message to
determine whether to process the message locally on the node 140 or
to route the message to another node in the routing table. For
example, upon receiving a create request from another node, the
routing module 305 examines the hop value to determine whether it
is greater than zero. If the hop value is greater than zero, the
routing module 305 decrements the hop value, randomly selects a
connected node in the routing table (subject to any specified
subdomain constraints, if applicable), and forwards the request and
decremented hop value to the selected node. If the hop value is
zero, the routing module 305 provides the request to the creation
module 310.
[0043] Similarly, upon receiving a write request, the routing
module 305 determines whether the DDID is associated with a DD
maintained by the node 140. If the DDID is not associated with a DD
maintained by the node 140, the routing module 305 forwards the
request to other nodes in its routing table. If, on the other hand,
the DDID is associated with a DD maintained by the node, the
routing module 305 provides the request to the write module 315.
The routing module 305 handles read requests, as well as other
requests described herein, in the same fashion.
[0044] The creation module 310 creates DDs in response to requests
received by the node 140. Upon receiving a create request from the
routing module 305, the creation module 310 generates a DDID to
represent the DD for the request. In addition, the creation module
310 generates a set of tokens associated with the DDID. The
creation module 310 provides the DDID and tokens to the recipient
110 that requested the DD using the path to the recipient's ingress
node 140A as described with respect to FIGS. 1 and 2.
[0045] In one embodiment, the creation module 310 generates the
DDID as a globally unique identifier (GUID). The DDID is a value
represented using a large number of bits (e.g., a 128-bit value). A
small portion of the bits may be fixed to identify the value as a
DDID or encode other information, while the other bits are randomly
generated by the creation module 310. The large number of bits
makes it extremely unlikely that the same DDID would be generated
for multiple DDs. Therefore, each DDID is unique for practical
purposes. The DDID may be represented as sequence of hexadecimal
digits.
[0046] In one embodiment, the tokens generated by the creation
module 310 may include a write token, a read token, and an owner
token. The write and read tokens respectively provide the bearer of
the token the rights to write data to, and read data from, the DD
associated with the DDID as described above. The owner token
provides the bearer with administrative rights to the DD, such as
the right to delete data within the DD or delete the entire DD.
[0047] In one embodiment, a token, like the DDID, is a value
represented using a large number of bits, some of which may be
fixed and others of which are randomly generated by the creation
module 310. The number of bits in each token may be fewer than the
number of bits in the DDID. Each token associated with a particular
DDID is unique with respect to other tokens associated with that
DDID.
[0048] The creation module 310 allocates space in the data storage
390 for the created DD and associates this space with the DDID. The
amount of space, and the time when the space is allocated may vary
in different embodiments. In one embodiment the creation module 310
allocates a fixed amount of storage space for the DD when creating
the DD. In another embodiment, the creation module 310 allocates
the storage space later, when receiving data to store in the DD.
Likewise, the amount of space allocated for the DD can vary in
different embodiments.
[0049] The write module 315 writes data to DDs in response to write
requests received by the node 140. Upon receiving a write request
from the routing module 305, the write module 315 initially
verifies the write token included in the request. The write module
315 identifies the
[0050] DDID and write token included in the request, and compares
the write token to the stored write token created by the creation
module 310 for the DDID. If the compared write tokens do not match,
the write module 315 denies the write request. Depending upon the
embodiment, the write module 315 can deny the request by acting as
if the request was not received (i.e., by not sending any messages
in response to the write request) or by sending a message to the
sender 120 indicating that the write token is invalid.
[0051] If the compared write tokens match, the write module 315
uses the return path in the write request to open a network
connection with the ingress node 140L for the sender 120. The write
module 315 receives data from the sender of the write request, and
writes the data to the storage allocated for the DD identified by
the DDID. In one embodiment, the write module 315 stores the data
in a DD as a series of discrete messages, such that the data for
each write request to a DD is saved as a logically separate
message. The stored messages for the DD are organized in a queue or
another data structure.
[0052] The read module 320 reads data from DDs in response to read
requests received by the node 140. Upon receiving a read request
from the routing module 305, the read module 320 initially verifies
the read token included in the request. The read module 320
identifies the DDID and read token included in the request, and
compares the read token to the stored read token created by the
creation module 310 for the DDID. If the compared read tokens do
not match, the read module 320 denies the read request. Like the
write module 315, the read module 320 can deny the request by
acting as if the request was not received (i.e., by not sending any
messages in response to the read request) or by sending a message
to the recipient 110 indicating that the read token is invalid.
[0053] If the compared read tokens match, the read module 320 uses
the return path in the read request to open a network connection
with the ingress node 140A for the recipient 110. The read module
320 reads data from the storage allocated for the DD, and sends the
data to the recipient 110 via the ingress node 140A. In another
embodiment, a direct connection is established between the node
storing the DD and the recipient 110 and the data is sent to the
recipient without passing through the ingress node 140A. If the
data in the storage is organized in a queue, an embodiment of the
read module 320 sends the message in the queue in response to the
request (e.g., in a first-in-first-out order) and removes the
message from the queue after it is sent. Other embodiments may send
multiple messages per read request and/or leave message in the
queue after the messages are sent to the recipient 110. In another
embodiment, the contents of a DD are not read, for example, because
the holder of a read token corresponding to the DD no longer wishes
to communicate with the sender of the message. In this case,
communication may be disconnected unilaterally by the recipient,
without action, consent, or knowledge by the sender.
[0054] The TTL module 325 maintains TTL information for the node
140. The TTL information generally describes for how long an entity
persists in the domain 130. For example, DDs, DDIDs, tokens, and
data written to DDs may have associated TTL information that
describes how long the respective entities persist within the
domain 130. Once the duration described by the TTL is reached, the
entity to which the TTL pertains expires, is no longer recognized
as valid, and may be deleted.
[0055] In addition, the TTL module 325 enforces the TTLs by
detecting when a duration described by a TTL is reached, and
invalidating the entity associated with the TTL. For example, if
the TTL module 325 detects that a TTL for a DD is reached, the TTL
module deletes the data stored within the DD and also deletes or
otherwise invalidates the DDID and tokens associated with the DD so
that the DD can no longer be accessed. Similarly, if the TTL module
325 detects that a TTL for data written to a DD is reached, the TTL
module 325 deletes the data from the DD so the data can no longer
be read.
[0056] The TTL information may be specified as a counter (e.g., a
duration of time from the present time) or as a timestamp (e.g., an
explicit time after which the entity is no longer valid).
Additionally, the TTL may be specified as a number of instances of
particular types of access (e.g., a DD expires once it is read from
3 times, or written to once). Further, the TTL information may be
specified as a category (e.g., "default," "short," "medium,"
"long," or "confidential"). In the latter case, the TTL module 325
converts the category description to a counter or timestamp based
on a TTL policy. Different entities may have different applicable
TTL policies. For example, the TTL policies may specify that the
"default" TTL for a DD is 30 days and the "default" TTL for a
message is 7 days. The TTL module 325 may also support an "archive"
TTL that does not expire, therefore making the entity having the
TTL persistent.
[0057] In one embodiment, the recipient 110 specifies the TTL for a
DD when creating it. For example, the TTL information may be
embedded into the create request. Likewise, the sender 120 may
specify the TTL for data by embedding the TTL in the write request.
For example, the recipient 110 may specify a specific amount of
time or number of instances of access for which the DD is valid, or
specify a category as discussed above. The TTL specified for the DD
is embedded into the create request and received by the TTL module
325.
[0058] The data control module 330 supports management of DDs for
the nodes 140 of the domain 130. The data control module 330
provides a variety of management functions that can be accessed by
the recipient 110 or other entity making a request for a particular
function and providing tokens granting administrative authority,
reading privilege, writing privilege, etc. for a given DD.
[0059] In one embodiment, the data control module 330 provides a
movement function that moves a DD from one node 140 to another node
while maintaining the same DDID. The recipient 110 may issue a move
request that contains the DDID, the owner token and, optionally, a
specification of a node to which the DD should be moved. In various
embodiments, movement of a DD may be initiated by a user request,
environmental factors (e.g., a node 140 is scheduled to be taken
offline, time of day), or a policy definition (e.g., a DD may only
stay on a specific node 140 for a certain time before it is
required to be moved). The node 140 to which the DD should be moved
may be specified, for example, by indicating a subdomain to which
the DD should be moved. In response to a move request having a
valid owner token, the data control module 330 of the node 140
having the DD identified by the DDID identifies a new node to which
the DD is to be moved. For example, the data control module 330 may
randomly select a new node within the specified subdomain using the
random selection technique described above and send that node a
message identifying the DDID and the data for maintaining in the DD
identified by the DDID. A data control module 330 in the new node
140 establishes a new DD under the existing DDID, and stores the
received data in that DD. Once the new DD is established, the data
control module 330 may optionally delete the DD identified by the
DDID so that the DD has effectively been moved to the new node.
[0060] The data control module 330 also provides a replicate
function that replicates a DD from a node 140 to one or more other
nodes. The replication is similar to the movement function, except
that the original data control module 330 does not delete the DD
identified by the DDID after the new DD is created. In one
embodiment, replication is initiated by a recipient 110. In another
embodiment, replication is initiated automatically (e.g., by
executable instructions stored in the DD that specify rules for
replication). When a node 140 containing a replicated DD fulfills a
write request, the routing module 305 forwards the write request to
other nodes in the routing table so that each instance of the
replicated DD may fulfill the write request and maintain data
currency.
[0061] The data control module 330 further provides an archive
function that stores an archive of a DD in another node 140. To
perform the archive, the data control module 330 of the node 140
storing the DD receives an archive request similar to the move
request. The data control module 330 communicates with the data
control module 330 of the new node 140 to create a new DD
associated with the same DDID. The data control module 330 sets the
TTL for the entities associated with the new DD as "persistent,"
meaning that the new DD acts as an archive for the DD in the
original node. The data control module 130 of the original node 130
may optionally delete the DD identified by the DDID after the
archive is created.
[0062] The delete module 335 deletes DDs from a node 140. The
delete module 335 receives a delete request from the recipient 110
or another entity. The delete request contains a DDID and the
associated owner token. The delete module 335 verifies that the
received token grants delete privileges and, if it does, deletes
the DD identified by the DDID from the node 140. In another
embodiment, delete module 335 may delete one or more messages
stored in a DD and not the entire DD itself. In one embodiment, the
delete module 335 writes data to the storage location from which
the DD is deleted. This writeover data may be randomly generated or
predetermined. Writing writeover data makes recovering deleted data
more difficult. It also makes finding DD data more difficult by
increasing the total amount of stored data in the storage location,
with the multiple instances of writeover data obfuscating DD
data.
[0063] A notification module 340 provides notifications to other
modules of the node 140, other nodes 140, or external destinations
(e.g., push notifications, mobile device notifications, emails,
phone calls, text messages, etc.) when an event takes place. An
event is a change in state in a node 140. Examples of events
include data being written to a DD (including data being written to
a DD a specified number of times), data being read from a DD
(including data being read from a DD a specified number of times),
data being deleted from a DD, data control functions (moving data,
replicating data, archiving data, etc.), TTL functions (TTL
expiration, TTL changes, TTL creation, TTL deletion, etc.), actions
performed by a node, and time instances (a clock reading a
particular time, a timer expiring, etc.). In one embodiment, the
notification module 340 of a node 140 receives a notification
request from a module of the node 140, a different node 140, a
recipient 110, or another entity. The notification request
specifies the event for which the notification is to be created.
For events relating to DDs, the notification request includes the
DDID and a token (e.g., owner token, read token) associated with
the DDID. The notification request further includes a notification
address to which a notification is to be made when the event
occurs. In one embodiment, the notification address is specified in
the form of a DDID and write token for a different DD in the domain
130. The notification address may be specified as a different form
of address, such as an address on the Internet to which an email or
another form of message may be sent.
[0064] The notification module 340 determines whether the token for
a DDID in a notification request is correct. If the token is not
correct, the notification module 340 rejects or otherwise ignores
the notification request. If the token is correct, the notification
module 340 examines the notification request to identify the type
of event for which the notification is requested. The notification
module 340 then creates a notification for the event. In one
embodiment, the notification module 340 establishes a trigger that
detects when the appropriate type of event occurs for the
identified DD. To this end, the notification module 340 may monitor
the activities of the other modules (e.g., the write module 315) to
determine when such events occur. For example, if the notification
request specifies a write event, the notification module 340 may
monitor the write module 315 to detect writes to the indicated
DD.
[0065] When the requested event is detected, the notification
module 340 generates and sends a notification to the specified
notification address. The notification may identify the DD to which
the event occurs (e.g., by including the DDID in the notification)
and the type of event that occurred (e.g., a write to the DD having
the DDID). If the notification address is for a DD, the
notification module 340 acts as a sender 120 and uses the write
token and DDID specified in the notification request to write the
notification to the DD. In this example, the recipient 110 or other
entity that requested the notification can monitor a single DD to
receive notifications about events occurring in multiple different
DDs. If the notification address is specified as a different form
of address, the notification module 340 sends the notification
using the appropriate technique for the address.
[0066] A geo-fence module 345 receives and analyzes
geographic-related restrictions associated with the DD or requests
received by the DD. The geo-fence module 345 communicates with the
other modules in the DD to enforce such restrictions. The
restrictions may specify that a DD is only accessible by senders
and recipients within a geographic area specified by the creator of
the DD. Access may be restricted in various ways in different
embodiments. For example, in one embodiment, requests received by a
DD may be valid only if the originator of the request is located
within a certain geographic area. In another embodiment, a DD or
specific contents of the DD may be accessible only if a specified
party (e.g., owner, recipient, sender, third party, etc.) is within
a certain geographic area. The geo-fence module 345 may also
communicate with the notification module 340 to send notifications
when events (e.g., write requests, read requests, etc.) occur
within specified geographic areas.
[0067] A monitoring module 350 detects events and sends action
messages to an action module 355 upon detection. The monitoring
module 350 can monitor events within the node 140 or outside of the
node 140, such as at a different node 140. To monitor events
occurring outside of the node 140, the monitoring module 350 may
send a notification request to one or more notification modules 340
of other nodes 140. The notification request may identify the event
for which notification is requested and include a notification
address identifying the node making the request. The notification
request is received by a notification module 340 of the other node,
and a notification is sent to, and received by, the monitoring
module 350 in the first node when the event occurs. To monitor
events within the node 140, the monitoring module 350 may send a
notification request to the notification module 340 of the node
140, or the monitoring module may communicate directly with other
modules of the node 140 to determine when the event occurs.
[0068] Trigger messages specify events to be monitored and actions
to be performed if the events are detected. Trigger messages may be
sent by users, system administrators, software developers, other
modules of the node 140, other nodes 140, applications, etc.
Trigger messages are received by the monitoring module 350, and the
monitoring module monitors the specified events. In one embodiment,
trigger message contents are stored in the data storage 390. In
another embodiment, trigger message contents are stored in a DD
accessible to the monitoring module 350 and the action module
355.
[0069] The action module 355 performs actions when events are
detected. An action is a function performed in response to a change
in state in a node 140. Examples of actions include notifications,
notification requests, command sequences, writing to a DD, reading
from a DD, deleting data from a DD, deleting a DD, data control
functions (moving data, replicating data, archiving data, etc.),
TTL functions (TTL expiration, TTL changes, TTL creation, TTL
deletion, etc.), and sending messages (e.g., to address on the
Internet to which an email or another form of message may be sent).
Command sequences may include instructions sent to systems or
devices connected to the node 140. The action module 355 is
informed by the monitoring module 350 when an event is detected,
and performs the actions specified in a trigger message.
[0070] In one embodiment, events and actions are connected to
perform multiple actions in sequence upon detection of an event. A
first action performed in response to a first event may also be
specified as a second event with a corresponding second action. For
example, a first trigger message specifies a first event as a read
from a first DD and a first action as a write operation a second
DD. Accordingly, when the first DD is read from, the second DD is
written to. A second trigger message specifies a second event as a
write operation to the second DD and a second action as an email to
an email address.
[0071] A scheduling module 360 determines when an action is
performed relative to an event. In one embodiment, a trigger
message includes a specified time at which an action occurs. The
specified time may be expressed as a counter (e.g., a duration of
time after the event is detected) or as a timestamp (e.g., an
explicit time at which the action occurs). In another embodiment,
an event is a time instance, such as a timer expiring or a clock
reaching a certain time. The scheduling module 360 communicates
with the action module 355 to perform the action at the specified
time. For example, upon detection of an event, the scheduling
module 360 may instruct the action module 355 to wait to perform
the action until the specified time or until further instructions
are received from the scheduling module.
[0072] A handshake module 365 facilitates direct connections
between two or more nodes 140 that may otherwise be unable to
connect due to network security policies, such as firewall
policies. In one embodiment, the handshake module 365 performs dual
functions. First, a handshake module located in a handshake node
140 provides functionality allowing establishment of a direct
connection between two other nodes using respective handshake
modules in the other two nodes. Second, the handshake module 365 in
a node 140 establishes a direct connection with the handshake
module of another node by exchanging data using the handshake
module of a handshake node. In other embodiments, the handshake
module 365 may perform only one of these functions and/or perform
additional functions.
[0073] An embodiment of the handshake module 365 performs the first
function--allowing two other nodes to establish a direct
connection--by exchanging handshake information between the two
nodes. Handshake data may include network address information such
as IP addresses and port addresses and/or information describing
characteristics of the nodes. In one embodiment, the handshake
module 365 within the handshake node allows for the creation of a
DD for the purpose of exchanging handshake information. The node on
whose behalf the DD is created receives the associated DDID and may
provide the DDID to the other node with which the direct connection
is to be established. The two nodes that will be party to the
direct connection may then exchange handshake information using the
handshake node.
[0074] An embodiment of the handshake module 365 performs the
second function--establishing a direct connection with the
handshake module of another node--identifying a handshake node that
can be used to exchange information with the other node. In one
embodiment, the handshake module 365 maintains a directory of
handshake nodes. The handshake module 365 selects a particular
handshake node from the directory and exchanges the identity of the
selected handshake node with the handshake module of the other node
via an indirect connection. Once the handshake modules 365 of the
two nodes know the identity of the handshake node, the handshake
modules 365 respectively connect to the handshake node to exchange
information and establish a direct connection.
[0075] FIG. 4 is a flowchart illustrating steps for using a DD to
pass data from a sender 120 to a recipient 110 according to one
embodiment. FIG. 4 describes the steps from the perspective of a
node 140 of a domain 130. Other embodiments may include different
and/or other steps than those described herein, and the steps may
be performed in different orders. Likewise, some or all of the
steps may be performed by entities other than the node 140 in other
embodiments.
[0076] The node 140 receives 410 a create request. As described
above, a recipient 110 can issue the create request and send the
request to an ingress node 140A in the domain 130. The ingress node
140A randomly selects a node to service the request. Assume, then,
that the node 140 receives 410 the create request after having been
randomly selected to service it. In response to the create request,
the node 140 generates 415 a DDID and a set of associated tokens
for the new DD. In addition, the node 140 may allocate storage
space for storing data written to the DD. The node 140 provides the
tokens and DDID to the recipient 110.
[0077] Subsequently, the node 140 receives 420 a write request
including the DDID and associated write token. The write request
may have been issued by a sender 120 who received the DDID and
write token from the recipient 110. The sender 120 sends the write
request to an ingress node 140L in the domain 130 which, in turn,
forwards the write request to other nodes in the domain until it
reaches the node that created the DD associated with the DDID. The
node 140 determines whether the write token is valid. If the token
is valid, the node 140 responds to the write request by
establishing a connection with the sender's ingress node 140L. The
node 140 receives the data to be written to the DD from the sender
120 via the ingress node 140L and stores 425 the data in the DD. If
the token is not valid, an embodiment of the node 140 does not
respond to the write request. In another embodiment, if the token
is not valid, the node 140 sends a message indicating the request
is rejected.
[0078] The node 140 later receives 430 a read request including the
DDID and associated read token. The read request may have been
issued by the recipient 110 who established the DD identified by
the DDID. Similar to a write request, the recipient 110 sends the
read request to an ingress node 140A in the domain 130 which
forwards the read request to other nodes in the domain until it
reaches the node that created the DD associated with the DDID. Upon
receiving the read request, the node 140 determines whether the
read token is valid. If the token is valid, the node 140 responds
to the read request by establishing a connection with the
recipient's ingress node 140A and sends it the data from the DD.
For example, if the DD is maintained as a queue, the node 140 will
send the data that is next in the queue. If the token is not valid,
an embodiment of the node 140 does not respond to the read request.
In another embodiment, if the token is not valid, the node 140
sends a message indicating the request is rejected.
[0079] FIG. 5 is a flowchart illustrating steps for using a DD to
monitor events and perform actions if an event is detected
according to one embodiment. A trigger message is received 505 by
the monitoring module 350. The trigger message specifies an event
to be monitored, and one or more actions to be performed if the
event is detected. The trigger message may be stored in data
storage 390 or a DD. Responsive to the trigger message being
received, the monitoring module 350 begins 510 monitoring for the
occurrence of the event. For example, the monitoring module 350 may
send one or more notification requests to monitor the event, or a
timer or clock may be set by the scheduling module 360. When the
event occurs, the event is detected 515 by the monitoring module
350. The monitoring module 350 informs 520 the action module 355
that the event has occurred. The action module 355 determines the
set of actions associated with the event by the trigger message and
performs 525 the actions. In one embodiment, when the action module
performs the set of actions, the monitoring module 350 deletes the
trigger record such that the action only occurs once in response to
the event detection. In another embodiment, the trigger record
persists, allowing the set of actions to be performed each time the
event is detected.
[0080] FIG. 6 is a high-level block diagram illustrating an example
of two nodes establishing a direct connection according to one
embodiment. Specifically, FIG. 6 illustrates a first node 140X
establishing a direct connection with a second node 140Y. FIG. 6
also illustrates a handshake node 140Z. In FIG. 6, nodes 140X and
140Y are protected by respective network security systems 610X and
610Y. The network security system 610 may be, e.g., a firewall. The
network security system 610 may filter, block, or otherwise prevent
certain inbound network communications from reaching a node 140.
The two nodes 140X, 140Y establishing the direct connection can
overcome the respective network security systems 610X, 610Y by
exchanging handshake information using the handshake node 140Z.
[0081] In one embodiment, the node 140X establishing the direct
connection accesses the handshake directory which is maintained, or
otherwise accessible via, the node's handshake module 365. The node
140X selects the handshake node 140Z, and sends an identifier of
the selected handshake node to the other node 140Y that will be
party to the direct connection. The node 140X may send the
identifier of the handshake node 140Z to the other node using an
indirect connection over the DD domain 130, using standard
networking communications, and/or via other techniques. In one
embodiment, the node 140Y that receives a direct connection request
with an identifier of a handshake node 140Z will verify that the
handshake node is also included in its handshake directory. Once a
handshake node 140Z is selected and known to both nodes 140X and
140Y, nodes 140X and 140Y may form a direct connection by
exchanging handshake information via the handshake node 140Z.
[0082] FIG. 7 is a high-level block diagram illustrating physical
components of a computer 700 used as part or all of one or more of
the entities described herein in one embodiment. For example,
instances of the illustrated computer 700 may be used as the
recipient 110, sender 120, and/or a node 140 in the domain 130.
Illustrated are at least one processor 702 coupled to a chipset
704. Also coupled to the chipset 704 are a memory 706, a storage
device 708, a keyboard 710, a graphics adapter 712, a pointing
device 714, and a network adapter 716. A display 718 is coupled to
the graphics adapter 712. In one embodiment, the functionality of
the chipset 704 is provided by a memory controller hub 720 and an
I/O controller hub 722. In another embodiment, the memory 706 is
coupled directly to the processor 702 instead of the chipset 704.
In one embodiment, one or more sound devices (e.g., a loudspeaker,
audio driver, etc.) is coupled to chipset 704.
[0083] The storage device 708 is any non-transitory
computer-readable storage medium, such as a hard drive, compact
disk read-only memory (CD-ROM), DVD, or a solid-state memory
device. The memory 706 holds instructions and data used by the
processor 702. The pointing device 714 may be a mouse, track ball,
or other type of pointing device, and is used in combination with
the keyboard 710 to input data into the computer 700. The graphics
adapter 712 displays images and other information on the display
718. The network adapter 716 couples the computer system 700 to a
local or wide area network.
[0084] As is known in the art, a computer 700 can have different
and/or other components than those shown in FIG. 7. In addition,
the computer 700 can lack certain illustrated components. In one
embodiment, a computer 700 acting as a node 140 may lack a keyboard
710, pointing device 714, graphics adapter 712, and/or display 718.
Moreover, the storage device 708 can be local and/or remote from
the computer 700 (such as embodied within a storage area network
(SAN)).
[0085] As is known in the art, the computer 700 is adapted to
execute computer program modules for providing functionality
described herein. As used herein, the term "module" refers to
computer program logic utilized to provide the specified
functionality. Thus, a module can be implemented in hardware,
firmware, and/or software. In one embodiment, program modules are
stored on the storage device 708, loaded into the memory 706, and
executed by the processor 702.
[0086] The above description is included to illustrate the
operation of certain embodiments and is not meant to limit the
scope of the invention. From the above discussion, many variations
will be apparent to one skilled in the relevant art that would yet
be encompassed by the spirit and scope of the invention.
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