U.S. patent application number 13/891111 was filed with the patent office on 2013-11-14 for system and method for managing latency in a distributed telephony network.
This patent application is currently assigned to Twilio, Inc.. The applicant listed for this patent is TWILIO, INC.. Invention is credited to Jonas Boerjesson, Christer Fahlgren, Peter Shafton, John Wolthuis.
Application Number | 20130304928 13/891111 |
Document ID | / |
Family ID | 49549547 |
Filed Date | 2013-11-14 |
United States Patent
Application |
20130304928 |
Kind Code |
A1 |
Fahlgren; Christer ; et
al. |
November 14, 2013 |
SYSTEM AND METHOD FOR MANAGING LATENCY IN A DISTRIBUTED TELEPHONY
NETWORK
Abstract
A system and method of preferred embodiments include at a
signaling gateway of a first region, receiving a communication
invitation of a first endpoint from a communication provider;
signaling the communication invitation to a
communication-processing server in a second region; in response to
communication processing of the communication-processing server,
dynamically directing signaling and media of the communication
according to processing instructions and resources available in at
least the first and two regions; wherein dynamically directing
signaling and media communication of the communication comprises
selectively routing media communication exclusively through
communication resources of the first region if resources are
available in the first region or selectively routing media
communication between the first endpoint, the gateway, and at least
the communication-processing server if media resources are not in
the first region.
Inventors: |
Fahlgren; Christer; (San
Francisco, CA) ; Boerjesson; Jonas; (San Francisco,
CA) ; Wolthuis; John; (San Francisco, CA) ;
Shafton; Peter; (San Francisco, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TWILIO, INC. |
San Francisco |
CA |
US |
|
|
Assignee: |
Twilio, Inc.
San Francisco
CA
|
Family ID: |
49549547 |
Appl. No.: |
13/891111 |
Filed: |
May 9, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61644886 |
May 9, 2012 |
|
|
|
Current U.S.
Class: |
709/227 |
Current CPC
Class: |
H04L 65/1006 20130101;
H04L 65/103 20130101; H04L 45/121 20130101; H04L 45/124 20130101;
H04L 45/125 20130101; H04L 65/1033 20130101; H04L 65/1069
20130101 |
Class at
Publication: |
709/227 |
International
Class: |
H04L 29/06 20060101
H04L029/06 |
Claims
1. A method for architecting a geographically distributed
communication computing platform comprising: at a SIP signaling
gateway of a first region, receiving a SIP communication
invitation, the communication originating from a first
communication endpoint directed through a provider service;
signaling a communication invitation to a communication-processing
server in a second region, wherein the first region and second
region are at least two thousand miles apart; at the
communication-processing server, retrieving application
instructions from an internet accessible server at a URI that is
associated with a destination endpoint of the communication
invitation; at the communication-processing server, processing the
retrieved application instructions; upon encountering an
instruction requiring media flow, establishing a media
communication flow with the first endpoint, querying a routing
policy service of the second region for a selected communication
route, and establishing a media communication flow with a resource
of the selected communication route; wherein establishing a media
communication flow with a resource of the selected communication
route comprises if the instruction includes communicating with a
second endpoint of the first region, establishing a communication
flow with a second gateway, the second gateway establishing
communication flow with the second endpoint through a provider
service of the first region, and signaling for media communication
to flow between the first and second endpoints through the first
and second gateways of the first region.
2. The method of claim 1, further comprising if the second endpoint
terminates media communication through the two gateways of the
first region, re-inviting the communication-processing server, and
the communication-processing server processing subsequent
application instructions.
3. The method of claim 1, wherein establishing a media
communication flow with a resource of the selected communication
route comprises if the instruction includes a media resource not in
the first region, the communication-processing server establishing
media communication flow with the media resource of the second
region, the communication gateway, and the first endpoint through
the gateway of the first region.
4. The method of claim 1, wherein the first and second endpoints
can be communicating with an audio medium, a video medium, or
screen-sharing medium.
5. The method of claim 4, wherein the first and second endpoints
communicate to the provider service with a PSTN protocol or a SIP
protocol.
6. A method for architecting a geographically distributed
communication computing platform with a subset of resources in a
first region and a subset of resources in a second region
comprising: at a signaling gateway of a first region, receiving a
communication invitation of a first endpoint from a communication
provider; signaling the communication invitation to a
communication-processing server in a second region; in response to
communication processing of the communication-processing server,
dynamically directing signaling and media of the communication
according to processing instructions and resources available in at
least the first and two regions; wherein dynamically directing
signaling and media communication of the communication comprises
selectively routing media communication exclusively through
communication resources of the first region if resources are
available in the first region or selectively routing media
communication between the first endpoint, the gateway, and at least
the communication-processing server if media resources are not in
the first region.
7. The method of claim 6, wherein routing media communication
exclusively through communication resources of the first region
comprises inviting a second gateway, the second gateway inviting a
second endpoint accessible through a provider service of the first
region, and the communication-processing server re-inviting the
first and second communication gateway to establish media
communication flow between the first and second communication
gateway and away from the communication-processing server.
8. The method of claim 7, wherein upon the second endpoint
terminating communication flow, re-establishing communication with
the communication-processing server.
9. The method of claim 7, wherein the first and second endpoints
are PSTN endpoints.
10. The method of claim 7, wherein the first and second endpoints
are client application endpoints.
11. The method of claim 6, wherein the signaling uses a SIP
signaling protocol.
12. The method of claim 6, wherein communication flow support the
first endpoint and second endpoint connecting to the provider
service through different communication mediums, the possible
communication mediums comprising audio, video, and
screen-sharing.
13. The method of claim 6, wherein the communication-processing
server is a call router; and further comprising the call router
retrieving telephony application instructions from an internet
accessible server at a URI that is associated with a destination
endpoint of the communication invitation, and processing the
retrieved telephony application instructions.
14. The method of claim 6, wherein the resources available in the
first region are media services.
15. The method of claim 14, wherein the media services comprise a
text-to-speech service, a recording service, and a transcoding
service.
16. A system for managing synchronous communication across regions
comprising: a communication-processing server in a first region
configured to retrieve application instructions from an addressable
resource associated with a destination endpoint of a communication
invitation and process the retrieved application instructions;
service provider interfaces in a second region with communication
to outside communication endpoints in the second region; a
communication gateway of the second region configured to
dynamically redirect signaling and media communication flow between
at least one endpoint of the second region and the
communication-processing server of the first region during the
duration of a synchronous communication session; wherein the first
region and the second region are within geographically distinct
regions wherein latency of media communication flow between the
first region and the second region is greater than latency of media
communication flow between endpoints of the second region.
17. The system of claim 16, further comprising a routing policy
server communicatively coupled to the communication-processing
server and configured to select a communication gateway for
communication between at least the first and second region during a
communication session.
18. The system of claim 17, wherein the signaling is SIP signaling;
and wherein the first and second communication endpoints can be a
PSTN endpoint or a client application endpoint.
19. The system of claim 18, wherein the communication medium
supported by the service provider interfaces in the second region
comprise audio communication, video communication, and
screen-sharing communication.
20. The system of claim 17, further comprising media resources of
the second region that are configured for media communication flow
within the second region independent of the
communication-processing server of the first region.
21. The system of claim 20, wherein the media resources comprise a
text-to-speech resource, a recording resource, and a media
transcoding resource.
22. The system of claim 16, wherein the distance between the first
region and the second region is greater than 2000 miles.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 61/644,886, filed on 9, May 2012, which is
incorporated in its entirety by this reference.
TECHNICAL FIELD
[0002] This invention relates generally to the telephony field, and
more specifically to a new and useful system and method for
managing latency in a distributed telephony network.
BACKGROUND
[0003] In recent years, innovations in the web application and
Voice over Internet Protocol (VoIP) have brought about considerable
changes to the capabilities offered through traditional phone
services. In some distributed or cloud-based telephony systems, the
routing of audio, video, or other media files can be determined or
limited by the location and/or availability of the appropriate
computing resources. In some instances, some or all of the callers
reside in the same region, country, or continent as the bulk of the
computing resources, thereby promoting increased call quality.
However, if one or more of the parties to the call is located in a
different region, country, or continent, then it is not readily
apparent which computing resources should be utilized. Similarly,
if the platform infrastructure is based in one region,
communication outside of that region will be poor quality. For
example, if the two callers reside in different countries, it might
be unclear which of many computing resources should be allocated to
the particular session. Furthermore, as more communication
platforms are supported by cloud computing services located in
distinct areas, core-computing infrastructure may be limited to
particular locations. Accordingly, there is a need in the art for
determining the shortest, highest quality, and/or optimized route
for session traffic in a globally distributed telephony system.
This invention provides such a new and useful system and method,
described in detail below with reference to the appended
figures.
BRIEF DESCRIPTION OF THE FIGURES
[0004] FIG. 1 is a schematic block diagram of a system and method
for managing latency in a distributed telephony network in
accordance with a preferred embodiment of the present
invention;
[0005] FIG. 2 is a schematic block diagram of a variation of the
preferred system and method for managing latency in a telephony
network;
[0006] FIG. 3 is a communication flow diagram of an example
implementation of the preferred method for managing latency in a
telephony network;
[0007] FIGS. 4A-4D are exemplary schematic representations of
communication flow between a first and second region;
[0008] FIG. 5 is a communication flow diagram of a variation
re-establishing communication of the preferred embodiment;
[0009] FIG. 6 is an exemplary representation of the system and
method of the preferred embodiment implemented within various
regions;
[0010] FIG. 7 is an exemplary communication flow diagram of an
implementation for a call between two PSTN devices of the method of
the preferred embodiment;
[0011] FIG. 8 is an exemplary communication flow diagram of an
implementation for a call between two client devices of the method
of the preferred embodiment;
[0012] FIG. 9 is an exemplary communication flow diagram of a
telephony application with dial followed by a text-to-speech
instruction;
[0013] FIG. 10 is an exemplary communication flow diagram of a
telephony application with a say instruction followed by a dial
instruction;
[0014] FIGS. 11 and 12 is an exemplary communication flow diagram
of a telephony application hanging up a call based on detected
input; and
[0015] FIGS. 13 and 14 are an exemplary communication flow diagram
of a caller or callee timing out.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The following description of preferred embodiments of the
invention is not intended to limit the invention to these preferred
embodiments, but rather to enable any person skilled in the art to
make and use this invention.
Preferred System
[0017] As shown in FIG. 1, a system 10 of the preferred embodiment
is configured for managing a distributed communication network
operation in at least two regions 12, 14. The preferred system 10
can be used with any suitable cloud-computing environment, such as
the one described in patent application Ser. No. 12/417,630 filed 2
Apr. 2009, entitled "System and Method for Processing Telephony
Sessions", which is incorporated in its entirety by this reference.
The system 10 preferably functions to provide the highest quality
path for communication between two endpoints in response to one or
both of a selected media type and/or the location/configuration of
the endpoints of the communications. As an example, the preferred
system 10 can function to minimize network latency between
different types of endpoints (mobile, PSTN, browser-based
telephony, client mobile devices, client browsers) using different
types of media (voice, video, text, screen-sharing, multimedia) and
disposed in different regions, countries, or continents. In one
preferred embodiment, the system 10 is configured for managing a
distributed telephony network, but may alternatively be configured
for mobile/browser client communication networks, video
communication, screen-sharing communication, synchronous media
communication, or any suitable communication network. In operation,
the preferred system can perform routing and latency minimization
in response to one or more of: the features/capabilities of the
endpoints; a media quality measurement (video and audio recording);
codec availability/compatibility; media resource availability;
and/or any suitable metric. During operation, the communication
flow of the system 10 will preferably shift between operations
modes--a first mode comprising communication flow between an
endpoint of a local region to a remote region with more resources
and a second mode comprising communication flow within the local
region. Communication flow is preferably a media data stream that
is used in the substantially real-time communication of media or
multimedia. An exemplary benefit of the system 10 is that complex,
stateful, or expensive communication resources may be maintained in
limited regions and other resources can be implemented globally or
regionally to support particular local regions. The limited
communication resources may be complex because they maintain
considerable state information of the platform, and replicating the
state information regionally/globally would result in increased
complexity and cost. Communication platforms, which may be
susceptible to global/regional scaling issues due to the real-time
nature of synchronous communication, can use the system to
dynamically switch between communicating within a local region and
communicating with resources of a remote region.
[0018] As shown in FIG. 1, the preferred system 10 is operable in
at least two regions 12, 14, which are connectable through and/or
serviced by a communication-processing server 16. The preferred
system 10 can also include one or more provider services (P1, P2,
P3, PN) and one or more gateways (X1, X2, XN) in the first region
12 and one or more communication-processing servers (H1, H2, H3,
HN) in the second region 14. The preferred system functions to
maintain functional communication when the first region 12 and
second region 14 are spatially separated by a globally significant
transmission distance. A globally significant distance in this
document may be understood to be a transmission distance greater
than 2000 miles and more preferably greater than 5000 miles. For
example, the first region 12 may be on the West coast of the US and
the second region 14 may be on the East coast, separated by a
geographic distance greater than 2500 miles. In another example,
the first region 12 may be in the United States and the second
region may be in Europe, separated by a distance greater than 3500
miles. The first region 12 and the second region 14 are not limited
to functioning with such distance ranges and may be separated by a
distance less than 2000 miles or exceeding 5000 miles.
[0019] The provider services (P1, P2, P3) preferably receive or
initiate communication to an endpoint such as a caller, a mobile or
browser client. The provider service is preferably an interface
between the communication platform of the system 10 and
communication providers. Communication providers preferably include
telephony carrier networks, client applications using IP based
communication protocols, or any suitable outside network. The
system 10 may include a plurality of regions in addition to the
first and second regions 12, 14. The provider services are
preferably specific to each region as they are determined by the
communication service providers, networks, and established
contracts with various communication entities.
[0020] Incoming communications to a destination endpoint are
preferably routed to the provider services in response to the
destination endpoint being registered with the system 10. For
example, a user dialing a PSTN number belonging to the system 10
will preferably have the communication directed to a provider
service (P1, P2, or P3). Another example, a user dialing a SIP
based endpoint that specifies a domain registered in DNS to the
system 10 will preferably have the communication directed to a
provider service (P1, P2, or P3). The provider additionally creates
invite requests and responses that are preferably sent to a
regional address (e.g., europe.twilio.com) and resolved to a
communication gateway. In some variations, communication may be
directly connected to a communication gateway to achieve a lower
latency audio/video. This may be particularly advantageous to
mobile and browser clients. The Domain Name System (DNS), anycast,
or any suitable addressing and routing methodology may be used to
forward to the closest communication gateway of a particular zone.
The provider services preferably use SIP protocol for communication
within the system, but the outside connected communication devices
may use any suitable communication protocol. Similarly, the medium
of the communication can preferably include any suitable
combination of possible media mediums such as audio, video,
screen-sharing, or other suitable synchronous media mediums.
[0021] The communication gateways (X1, X2) are preferably
configured for both media and signaling. A communication gateway
preferably mediates Session Initiation Protocol (SIP) signaling
between at least one endpoint of a communication, from call
establishment to termination. SIP is a signaling protocol widely
used for controlling communication sessions such as voice and/or
video calls over Internet Protocol. Any suitable communication
protocol such as RTP or combination of protocols may alternatively
be used. As a SIP mediator, the communication gateway preferably
creates SIP invites, issues other SIP signaling messages, and
facilitates transfer of media (e.g., audio, video) between various
end-points. The communication gateways (X1, X2, XN) are preferably
logical network elements of a SIP application, and more preferably
configured as back-to-back user agents (b2bua) for one or both of
media and signaling control. A b2bua, as would be readily
understood by a person of ordinary skill in the art, preferably
operates between endpoints involved in a communication session
(e.g., a phone call, video chat session, or screen-sharing
session). The b2bua also divides a communication channel into at
least two communication legs and mediates signaling between the
involved endpoints from call establishment to termination. As such,
the communication gateway can facilitate switching the
communication flow from flowing through a remote region (to use
remote resources) to flowing just within the local region (e.g.,
when establishing a call with another endpoint in the local
region). The communication gateway may additionally include media
processing components/resources such as Dual-tone Multi-frequency
(DTMF) detector, media recorder, text-to-speech (TTS), and/or any
suitable processor or service. The media processing and signaling
components of a communication gateway may alternatively be divided
into any suitable number of components or services in cooperative
communication. In one variation, the communication gateway is
implemented by two distinct components--a signaling gateway that
handles the signaling and a media gateway that handles media
processing and media communication. In an alternative embodiment,
the communication gateways may be configured as a control channel
that functions to allow devices to directly communicate
peer-to-peer. Browser clients, mobile clients, or any suitable
combination of clients may have direct media communication in this
variation. This alternative embodiment is preferably used with
low-latency media. As an additional security precaution,
communication gateways may be configured to allow traffic from only
a distinct set of providers. Other providers are preferably
firewalled off to protect infrastructure from the public Internet.
The communication gateways will preferably respond to
communications and/or propagate the communication messages to a
communication-processing server. The communication-processing
server may be in a different remote region. Load balancers may
additionally facilitate a communication propagating from a
communication gateway to an optimal communication-processing
server. For example, there may be multiple remote regions with
available communication-processing servers that can service a
communication. A load balancer or alternatively a routing policy
engine may direct the communication to an appropriate the region
and/or communication-processing server.
[0022] The communication-processing servers (H1, H2, H3) function
to process communication from a communication gateway. A
communication-processing server preferably provides value-added
features or services to a communication. A preferred
communication-processing server is preferably a call router or
telephony application processing component as described in patent
application Ser. No. 12/417,630 referenced and incorporated above.
A communication-processing server (or more specifically a call
router) will preferably retrieve an addressable application
resource (e.g., HTTP URI address document) associated with the
phone number or communication indicator. In a preferred embodiment,
the resource is a telephony application that indicates sequential
telephony commands for the communication session of the client(s).
The telephony commands may include instructions to call another
communication endpoint, to start a conference call, to play audio,
to record audio or video, to convert text to speech, to transcribe
audio, to perform answering machine detection, to send text or
media messages (e.g., SMS or MMS messages), to collect DTMF key
entry, to end a call, or perform any suitable action. The telephony
instructions are preferably communicated in a telephony instruction
markup language such as TwiML. The addressable resource is
preferably hosted at the HTTP Server 16. The servers (H1, H2, H3)
and HTTP server 16 communications are preferably RESTful in nature
in both/all directions. RESTful is understood in this document to
describe a Representational State Transfer architecture as is known
in the art. The RESTful HTTP requests are preferably stateless,
thus each message communicated from any component in the system 10
preferably contains all necessary information for operation and/or
performance of the specified function. Signaling will preferably be
transferred through the server, but media may not be transferred
through the server.
[0023] The communication-processing server is preferably part of a
telephony application platform and may cooperatively use several
other resources in operation. The communication-processing server
may be a central component to the service provided by a platform
and as such may be associated with considerable stateful data
generated in use of the server. The stateful data may be used in
internal logic and operation of the platform and/or for providing
API accessible data and information. The system 10 is preferably
implemented in a multi-tenant environment where multiple accounts
share/operate with the same resources. As such, there may be
benefits in keeping the communication-processing servers centrally
located in a limited number of regions. Since the
communication-processing server may not be located in each local
region, a local region may call out, bridge or otherwise
communicate with a remote region that does hold a
communication-processing server. As mentioned above, the
communication-processing server may provide any suitable processing
services in addition to or as an alternative to the call router
variation described above.
[0024] As shown in FIG. 1, the preferred system 10 can route
communication traffic between User 1 and User 2, wherein the
communications traffic can include any suitable media type, device
endpoint type, and/or network type usable in a suitable cloud-based
communications system of the type described above. In an example of
the preferred system's 10 operation, when User 1 wants to
communicate with User 2 (a PTSN number that is part of the
cloud-based system), his call is routed to provider P2. As
described below, the number dialed is preferably associated with a
URL or other identifier usable in the aforementioned
cloud-communications system. Preferably, provider P2 creates a
corresponding invite request in block 100 and sends it to a
predefined server address (e.g., europe.twilio.com,
us.sub.--1.twilio.com, us.sub.--2.twilio.com, etc.), which in turn
resolves to communication gateway X1. Upon receipt, the
communication gateway X1 preferably transmits or forwards the
request to communication-processing server H3 in block S102, which
as shown can be located in the second region 14. The server H3
functions to query the HTTP server 16 associated with the URL of
the dialed number in block S104 to determine, receive, download,
and/or capture any instructions, commands, or content associated
with the dialed number. The HTTP server 16 is preferably an outside
server managed by a developer or administrating entity. In a simple
example, the server H3 contacts the HTTP server 16 and receives a
single command (i.e., a "dial" verb) associated with the number.
Other suitable commands, each of which can be referred to as a
TwiML verb in the example embodiment, can include saying text to
the caller, sending an SMS message, playing an audio and/or video
file, getting input from the keypad, recording audio or video,
connecting the call to another phone, or any other suitable type or
media of communication.
[0025] As shown in FIG. 1, in block S106 the HTTP server 16 returns
the TwiML to server H3, at which point the server H3 processes the
TwiML to determine the particulars of the initial request, i.e., to
whom the call is directed, where the other endpoint is located,
what type of media is being directed to the second user, and the
like. In the example embodiment shown in FIG. 1, the second user is
located in the first region 12 with the first user, and therefore
the server H3 returns the invite request back to communication
gateway X1 for further processing in block S108. Upon receipt, the
communication gateway X1: determines that the inbound request is
related to the prior invite request received in block S100; and
transmits the request to a predetermined provider P3 in block S110
for eventual connection of the communication to the second user
from P3. Preferably, upon connection between provider P3 and the
second user, the communication traffic between the first and second
users will flow directly between the providers P2 and P3 in block
S112 with little to no input from any other component of the
preferred system 10 in the second region 14. In one variation of
the preferred system 10, media files and/or functionality are
stored at and/or performed by one or more of the communication
gateways X1 working alone or in combination with each other or
additional servers, databases, and/or controllers. As will be
described in further detail below, the communication traffic may be
subsequently dynamically redirected to route through the server H3.
For example, one of the endpoints may hang up, and the remaining
endpoint may have communication traffic flow from the endpoint of
P1 to X1 to H3 and back during the execution of other communication
instructions.
[0026] As shown in FIG. 2, one variation of the preferred system 10
can additionally include a routing policy server 50 in
communication with the communication gateway XN 20 and/or a
communication-processing server H3, and further include a SIP API
30 in communication with both the communication gateway 20 and
server HN 40. In one example configuration of the preferred system
10, the communication gateway 20 functions in part as a
back-to-back user agent (b2bua) for one or both of media and
signaling control. As an example, the communication gateway 20 can
be configured to handle multiple types of re-invite scenarios and
to transfer audio, video, or other media between various
communicating endpoints. Preferably, the communication gateway 20
can be configured to record audio or video streams and/or play any
suitable type of media file (e.g., addressed to a URL). In other
configurations of the preferred system 10, the communication
gateway 20 can be configured as a real-time transport protocol
(RTP) hub for handling RTP communications, RTP events, and/or
generating/consuming RTPC sender and receiver reports. As described
below, the RTPC reports can be transmitted and/or made available to
the policy server 50 such that the policy server 50 has real-time
or near real-time information about the quality of different
traffic routes in the larger system 10. In another variation of the
preferred system 10, the communication gateway 20 can be configured
as a single component/unit that handles both media and signaling
processes. Alternatively, the communication gateway 20 can be
configured as two distinct components (media and signaling)
residing on one or more nodes in the larger system 10 environment
or in any other suitable configuration or deployment in a
distributed network.
[0027] As shown in FIG. 2, the present variation of the preferred
system 10 can include a routing policy server 50 in communication
with the communication-processing server and/or the communication
gateway 20. The routing policy server 50 preferably functions to
optimize the flow of traffic throughout the preferred system 10 by
selecting and/or aiding in selecting the best available
communication gateway 20 (X1, X2, XN) and/or
communication-processing server (H1, H2) for routing the network
traffic. Preferably, the routing policy server 50 optimizes traffic
flow in response to one or both of the types/number/location of the
endpoints (browser, VoIP, PSTN, mobile/cellular) and the type of
media (voice, video, text, multimedia) used in each communication.
As shown in FIG. 2, the routing policy server 50 preferably
receives input/s from each of the communication gateways 20, for
example in the form of RTCP sender and receiver reports, which
enables the routing policy server 50 to determine in real time or
near real time the current status of each of the communication
gateways 20, and in turn to select the optimal communication
gateway 20 for any present network session. Preferably, one or both
of the communication gateway 20 and/or the server 4o can query the
routing policy server 50 for the optimal route, which can be
determined in response to one or more inputs received/requested
from the communication gateway 20. Additionally or alternatively,
the routing policy server 50 can receive from each communication
gateway 20 a live quality of service report from which the policy
server 5o can determine the current optimal route for any pending
sessions. In another variation of the preferred system 10, the
routing policy server 50 can apply a universal or generic routing
protocol between nodes without consideration of the type of media
being enjoyed in the communication session. In use, the preferred
policy server 50 can function to prevent overloading of any
particular node, server, or route in the preferred system 10 by
continuously and substantially simultaneously selecting and/or
aiding in the selection of the optimally configured communication
gateway 20 and/or server 5o for each pending session.
[0028] As shown in FIG. 2, the present variation of the preferred
system 10 can further include one or more application programming
interfaces (APIs) functioning and/or exposed by one or more
components in the preferred system 10. For example, a session
initiation protocol (SIP) API 30 is shown in FIG. 2 for
coordinating messages/communications between the communication
gateway 20 and the server 4o. Additionally or alternatively, the
routing policy server 50 can include one or more APIs for
determining the optimal route between two endpoints in the pending
communication. A preferred routing policy server 50 API can be a
RESTFul or any suitable alternative type of API. As noted above, in
one alternative configuration the communication gateway 20 can
include a media portion and a signaling portion, in which case the
media portion (not shown) can include an API (such as a REST or
Java API) to respond to media allocation requests from the
signaling portion (not shown) of the communication gateway 20. In
operation, a suitable communication gateway 20 API can expose one
or more functionalities (i.e., allocation of a media resource with
the following capabilities) and then return a resource identifier,
IP address, and/or port to where the media should be directed.
[0029] As shown in FIG. 2, the SIP API 30 can include one or more
additional headers and/or configurations for use in the preferred
system 10, including a regional header, an action header, a
features header, a support header, and/or a required header. In
this example implementation, the regional header can indicate a
zone from which the request is originating, including for example a
regional or sub-regional zone of Europe, Asia, North America,
and/or South America. The example action header can include
instructions for the receiver to perform one or more designated
actions, such as a "hang up" action. The example features header
can include one or more system 10 specific features, such as an
instruction to hang up if the user presses the star key on his or
her terminal, whether the hardware supports call recording, and the
like. The example support/required headers can include information
that identify any features, protocols, functions, and/or other
features that are desirable, optional, or necessary for properly
routing the session through any particular set of communication
gateways 20 and servers 40.
[0030] The system preferably can be configured to perform one or
more of the foregoing functions in a computer-readable medium
storing computer-readable instructions. The instructions are
preferably executed by computer-executable components preferably
integrated with the one or more communication gateways (X1, X2, XN)
in the first region 12, the one or more communication-processing
servers (H1, H2, H3, HN) in the second region 14, the HTTP server
16, the SIP API 30, and/or the routing policy server 50. The
computer-readable medium can be stored on any suitable computer
readable media such as RAMs, ROMs, flash memory, EEPROMs, optical
devices (CD or DVD), hard drives, floppy drives, or any suitable
device. The computer-executable component is preferably a processor
but the instructions can alternatively or additionally be executed
by any suitable dedicated hardware device.
Preferred Method
[0031] As shown in FIG. 3, a method of the preferred embodiment can
include receiving a communication invitation of a first endpoint
from a communication provider S210, signaling the communication
invitation to a communication-processing server in a second region
S220, dynamically directing signaling and media of the
communication according to communication processing instructions
and the resources available in at least the first and second
regions S230 that includes selectively routing media communication
exclusively through communication resources of the first region if
media resources to execute the processing instructions are
available in the first region S232 and selectively routing media
communication through at least the communication-processing server
if media resources are not in the first region S234. The system
functions to dynamically redirect traffic for signaling and media.
The method is preferably employed in a regionally/globally
distributed communication platform that works with communication
susceptible to latency performance issues. The method is preferably
used within a communication processing platform such as the
telephony platform incorporated by reference above. The method may
additionally or alternatively be used with video communication,
client based audio communication (e.g., VoIP), screen-sharing
applications, and/or any suitable communication platform.
Replicating all components in different regions can be expensive
and increase complexity of a system. The method enables components
to be intelligently and progressively rolled out to new regions (or
be statically implemented) without fully replicating the system
needed to support the features of a platform--some components may
be available in one region and some in others. Preferably, a
geographically distributed communication computing platform will
include a subset of resources in a first region and a subset of
resources in a second region. The subsets of resources are
preferably not identical sets (in terms of the function of the
components). A local region (used to service particular geographic
regions) is preferably a limited sub-set of a remote region (used
to provide core platform functionality). Preferably lightweight and
ancillary services and components (e.g., signaling and standalone
media processing services) are deployed in various regions to
support local communication endpoints, and more core or complex
resources (e.g., ones that maintain state within the platform) are
deployed in a limited number of regions, which are often remotely
located from the local regions. The method is preferably used to
implement communication instruction processing with a communication
stream between the first and second region as shown in FIGS. 4A and
4B, and when a media communication stream can flow exclusively
through the first region, dynamically establishing the
communication flow to not flow through intermediary media resources
of the second region, but instead to use media resources of the
first region as shown in FIGS. 4C and 4D.
[0032] Block S210, which includes receiving a communication
invitation of a first endpoint from a communication provider,
functions to initiate a communication session. Preferably a "call"
will be directed to the system through a provider service of the
first region. The called destination is preferably registered with
the system. For example, the telephony endpoint (the phone number,
phone number prefix, SIP address, the domain of the SIP address,
and the like) is used to route communication to the system in any
suitable manner. The provider services preferably ports or provides
a network access interface through which outside communication
networks connect to the system (and/or conversely, how the system
connects to the outside communication networks). A communication
will preferably include a call from an endpoint being directed
through outside networking to a provider service interface. The
provider service will preferably use SIP signaling or any suitable
protocol to direct a communication stream to a communication
gateway of the first region. A SIP communication invite is
preferably received at the communication gateway or more
specifically a SIP signaling gateway acting as a b2bua. Herein,
"calls" may refer to PSTN phone calls, IP based video calls,
screen-sharing sessions, multimedia sessions, and/or any suitable
synchronous media communication. Calls can additionally be mixed
medium/protocols. For example, a call (i.e., communication session)
may have one leg connect to a PSTN telephony device while a second
leg connects to a Sip based client application. Calls may
alternatively be initiated from within the system such as in
response to an API request or any suitable event.
[0033] Block S220, which includes signaling the communication
invitation to a communication-processing server in a second region,
functions to direct the communication to a communication-processing
server in another region. The other region (the second region) is
preferably spatially separate and remotely located from the first
region. The distance of separation is preferably a globally
significant distance. Within the US, the distance may be greater
than 2000 miles (across country). Across the globe, the distance
may be greater than 5000 miles. The communication gateway
preferably directs the communication signaling. As shown in FIG. 7,
the communication invitation is preferably a SIP invite but may
alternatively be a communication invitation of any suitable
protocol. The communication gateway may additionally query a
routing policy engine prior to transmitting the communication
invitation. The routing policy server will preferably determine an
appropriate routing of the call. Preferably the routing policy
server will identify the appropriate communication-processing
server in the second region. Additionally, the routing policy
server may consider communication-processing servers in a plurality
of regions (possibly including the first region). In another
variation, the routing policy server may detect that the resources
for processing the particular call can be handled within the first
region and direct that call appropriately within the first region.
For example, a particular phone number may not be configured for
telephony application processing and simply redirect to another
endpoint accessible through the first region. In this example, the
communication gateway may forego accessing a call router in a
second region, and establish media communication flow between the
first and second endpoint using resources of the first region.
[0034] The communication-processing server can provide any suitable
communication processing service. Preferably, the
communication-processing server acts as a call router that manages
execution of a communication session application. Processing a
communication application can include operations such as connecting
to endpoints, recording media, processing media (converting
text-to-speech, transcribing audio to text, transcoding between
media codecs), retrieving device inputs (e.g., DTMF capture),
sending messages or emails, ending calls, providing answering
machine detection, or providing any suitable service. In one
preferred variation, the method may additionally include, within
the second region, a communication-processing server retrieving
application instructions from an internet accessible server at a
URI that is associated with a destination endpoint of the
communication invitation. In this variation, the
communication-processing server is preferably a call router as
described in the incorporated patent application Ser. No.
12/417,630. The application instructions are preferably formatted
as markup instructions within a document retrieved over HTTP using
a web request-response model.
[0035] Block S230, which includes dynamically directing signaling
and media of the communication according to communication
processing instructions and the resources available in at least the
first and second regions functions to redirect communication to
appropriate regions. The directing of signaling and media is
preferably dynamically responsive to the active state of the
communication. Preferably, the signal and media direction is
responsive to application state of a communication. Application
state may include streaming media between two outside endpoints,
playing media from the system to an endpoint, processing or
recording media of a communication, or any suitable application
state. The communication routing is preferably changed to increase
the communication performance of the current state of a
communication. For example, if a first endpoint is connected to a
second endpoint, and the first and second endpoints are in the same
region, the communication media stream is preferably kept within
the first region. This can preferably reduce the amount of
communication latency that might be involved in routing through a
second region. In a contrasting situation, if the communication of
a first endpoint necessitates particular media processing not
available in the first region, a communication flow may be
established with a second region. Additionally, an application can
be configured with any suitable logic. For example, a call may be
responsive to a new connection to an endpoint, to one of two
endpoints hanging up, to initiating media processing (e.g., audio
recording, transcription, or DTMF detection), or to sending an out
of stream communication (e.g., SMS or MMS) and the like.
[0036] Block S232, which includes selectively routing media
communication exclusively through communication resources of the
first region if media resources to execute the processing
instructions are available in the first region, functions to route
communication within a region. The resources of the region are
preferably sufficient to support the current state of the
communication session. In a preferred variation, the media
communication is exclusively routed through the communication
resource of the first region for calls to other endpoints in the
region. Block S132 preferably includes a communication-processing
server inviting a second gateway, the second communication gateway
inviting a second endpoint accessible through a provider service of
the first region, and the communication-processing server
re-inviting the first and second communication gateways to
establish media communication flow between the first and second
endpoints. The communication is also directed away from the
communication-processing server of the second region. As a slight
variation, the media communication flow may even be established to
flow directly between the first and second endpoints without
passing through a gateway of the first region. The first and second
endpoints can be PSTN-based endpoints, SIP based endpoints, RTP
based endpoints or any suitable endpoint. An endpoint is preferably
any addressable communication destination, which may be a phone, a
client application (e.g., desktop or mobile application), an IP
based device or any suitable communication device. The endpoints
can use any suitable protocol and the first and second endpoints
may additionally use different communication protocols or
mediums.
[0037] Additionally or alternatively, routing media communication
exclusively through communication resources of the first region may
include selecting a media resource of the first region to
facilitate the media communication flow. In some cases, select
media resources may be deployed/implemented in the first region.
When the current communication media stream transitions to a state
where it requires only the media resources of the first region, the
media communication flow will preferably utilize the media
resources of the first region, rather than those of the remotely
located resources in the second region. For example, an application
may initiate a media recording instruction. If a recording resource
is in the first region, the communication gateway may direct
communication flow to go to the local recording server as opposed
to a recording server in a different region. In another example, a
media transcoding server may be accessed to transcode media for two
endpoints. Two endpoints may use different media codecs that are
not compatible. The transcoding service will preferably be added as
an intermediary in the communication flow so that the media can be
transcoded with low latency.
[0038] The method may include querying a routing policy service for
a selected communication route, which functions to dynamically
select a communication route. The routing policy server can use the
current state of the system, individual regions, individual
resources/services/components of a region, application state, or
any suitable parameter as an input. In one variation, the routing
policy service is substantially statically defined. A set of rules
and/or architecture configuration may be used to select the routes.
In another variation, the routing policy service performs an
analysis and selects a route that has statistical indications to be
an optimal route based on the analysis. The routing policy server
is preferably queried by the communication-processing server to
select communication gateways. The routing policy server may
additionally or alternatively be used by the communication gateway
to select a communication-processing server in block S220. There
may be one canonical routing policy server or multiple routing
policy server instances may be established in multiple regions.
[0039] Block S234, which includes selectively routing media
communication through at least the communication-processing server
if media resources are not in the first region, functions to route
communication between the first and second regions. This selective
option is preferably taken when the resource needed or preferred
for handling the communication session is not within the local
region (i.e., the first region). As with the initiation of a call,
the communication gateway preferably initially connects to a
communication-processing server. As was mentioned above, this
default behavior may not be taken if the next state of the
communication is known without accessing the
communication-processing server. Additional resources within the
second region may additionally or alternatively be used with the
communication-processing server. For example, media resources such
as recording service, text-to-speech servers, transcoding servers,
transcription/speech recognition servers, and/or any suitable media
resource may be implemented in the second region and may act on the
media communication flow.
[0040] As mentioned above, the directing of the communication can
dynamically change. The method may additionally include
re-establishing communication with the communication-processing
server upon a second endpoint terminating the media communication
flow S236 as shown in FIG. 5. Block S236 can function to enable the
communication to recover after communication flow has moved away
from a resource of the second region. As mentioned, the second
region preferably includes a communication-processing server that
can be configured for processing application state of a
communication session. Since the communication-processing server
may not be in the communication flow when two endpoints are
connected, a communication gateway in the first region will
preferably re-invite a communication-processing server and
reestablish communication flow between the first endpoint and the
communication-processing server. For example, two callers may be
talking in a first region. When the callee hangs up, the first
caller may be connected to a call router in a second region that
can play text to speech audio or perform any suitable application
action. The communication flow can be redirected any number of
times.
[0041] As shown in FIG. 6, the method may additionally be expanded
such that communication flow may be directed between any suitable
number of regions. In an exemplary implementation, there may be at
least two base regions in the US, with globally diversified local
regions such as one in Europe, one in Asia, and one in South
America. These regions may dynamically route communication based on
an optimal or preferred route. The preferred route may be based on
substantially static configuration of the different regions (e.g.,
how many resources are in each region), but may alternatively be
based on quality metrics such as latency, quality of service
reports, or any suitable metrics.
Example Implementations
[0042] As shown in FIG. 7, one example implementation of the system
and/or method of the preferred embodiment can include a telephone
call between a pair of PSTN telephone users. Those of skill in the
art will readily appreciate that the following description is of an
exemplary setting of the system and/or method of the preferred
embodiment and does not limit the claimed invention to any
particular aspect or feature described below. As shown in method
300 in FIG. 7, block S300 can include receiving a call invitation
at a first communication gateway X1 from a first user's POP (point
of presence provider or in other words a provider server). As noted
above, FIG. 7 illustrates a single use case in which the desired
communication is between two PSTN users. Accordingly, the content
of block S300 can include an invitation for a voice call
identifying both the media (voice) as well as the desired endpoint
(phone number to which the call is directed).
[0043] In block S302, the first communication gateway preferably
performs any necessary authentications, security checks,
verifications, and/or credential checks for one or both of the
caller and the recipient. Block S302 can additionally include
looking up and/or identifying a target uniform resource identifier
(URI) for the invitation, which designates the next destination for
the transmission, i.e., the suitable regional
communication-processing server H1 for the request. As shown in
FIG. 7, upon receipt of the request at the server H1, the server H1
responds to the communication gateway X1, which in turn propagates
the response back to the POP (point of presence) service (e.g., the
provider service) in block S304.
[0044] In block S306, the server H1 downloads and/or retrieves the
TwiML based on the URI associated with the dialed number (which
corresponds to an address in one variation of the preferred system
and method). Preferably, block S306 can further include determining
if there is any media associated with the session. Preferably, the
existence or requirement of a particular media can be determined
with reference to the TwiML, which can contain predefined actions
or verbs. Suitable actions or verbs can include dialing a number,
saying text to the caller, sending an SMS message, playing an audio
or video file, getting input from the keypad, recording audio or
video, connecting the call to another browser client or device, or
any other suitable type or media of communication. In the example
implementation, the TwiML would contain the "dial" verb, which
requires media. Following a series of mutual acknowledgements, the
transmission of media is opened up between the POP and the server
H1 in block S306.
[0045] As shown in FIG. 7, the example implementation can include
block s308, which includes determining an optimal route for the
media at the routing policy server. Preferably, block S308 is
performed substantially simultaneously with the series of
acknowledgements performed in block S306. Preferably, the policy
server 50 optimizes traffic flow in response to one or both of the
types/number/location of the endpoints (browser, VoIP, PSTN,
mobile/cellular) and the type of media (voice, video, text,
multimedia) used in each communication. As noted above, the routing
policy server preferably receives input/s from one or both of the
communication gateways X1 or X2, for example in the form of RTCP
sender and receiver reports, which enables the routing policy
server to determine in real time or near real time the current
status of each of the communication gateways X1 and X2, and in turn
to select an optimal communication gateway X2 for the proposed
call. Here optimal is used to indicate an algorithmically probable
best route. As shown in FIG. 3, the server H1 requests the optimal
route from the policy server in block S308. Additionally or
alternatively, the routing policy server can receive from each
communication gateway XN a live quality of service report from
which the policy server can determine the current optimal route for
any pending sessions.
[0046] As shown in FIG. 7, once the policy server determines the
optimal route (i.e., a second communication gateway X2), it will
return the appropriate URI to the server H1 so that the server H1
can communicate directly with the second communication gateway X2.
In block S310, the example implementation can include a series of
requests, invites, and acknowledgements between the server H1, the
second communication gateway X2, and the second POP destination of
the call recipient. Upon establishing the second leg of the
communication session, block S312 can include checking the two
endpoints (via first and second communication gateways X1 and X2),
and then permitting media to flow between the first and second
communication gateways X1 and X2 in block S314.
[0047] Preferably, the server H1 is not involved in the media flow
of block S314. Accordingly, another example implementation can
include detecting, at each of the first and second communication
gateways X1 and X2, whether each respective side of the session has
timed out for some reason. In response to a timeout at the first
communication gateway X1, the first communication gateway X1 will
alert the server H1, which in turn will hang up both the caller
side and the callee side of the session. Alternatively, if it is
the second communication gateway X2 that times out, then the server
H1 can be configured to only terminate or hang up on the callee
side in the event that there are more actions or verbs to execute
on the caller side.
[0048] The foregoing example implementation illustrates one aspect
of the preferred system and method using a single dial verb between
two PSTN users in a telephony system. However, the preferred system
and method can be readily configured for any suitable combination
of verbs, user types, and media types found in a cloud-based
communication network system. Some example alternative
implementations can include usage of the say verb, the hang up
verb, the gather verb, either alone or in combination with the dial
verb described above.
[0049] As shown in FIG. 8, a second exemplary implementation of the
system and/or method of the preferred embodiment can include video
streaming between two mobile devices. In this example, client
mobile or browser devices may connect directly to communication
gateways X1 and X2. This variation functions in a substantially
similar manner to the above example but may vary in communication
medium/protocols and user devices. In this variation, block S400
may include receiving a video invitation at a first communication
gateway X1 from a mobile device. Alternatively, a video invitation
may be received at a first communication gateway X1 from a POP.
Blocks S402, S404, S406, S408, S410, and S412 are substantially
similar to steps S302, S304, S306, S308, S310, and S312 except in
implementation differences accommodating for video streaming and
direct connection of the mobile devices to the communication
gateways. These blocks preferably establish two legs of a
communication session such that video can flow between the first
and second mobile device in block S414.
[0050] As shown in FIG. 9, a third exemplary implementation of the
system and/or method of the preferred embodiment can accommodate a
dial followed by a text-to-speech command. This is preferably an
extension of method 300 above, where a user handing up re-invites
between the communication-processing server and the communication
gateway can occur multiple times throughout the lifetime of a call.
A communication will preferably be initialized as described above
so that media communication flows between two endpoints of a first
region. One of the endpoints hangs up causing a SIP BYE signal to
be sent to a second communication gateway (X2). X2 then propagates
the BYE to the communication-processing server (H1) in the second
region. The H1 in this scenario will evaluate the application
instructions. If more instructions exist within the application,
then the H1 can re-invite the first endpoint to bring media
communication flow back to the H1 The H1 re-invites the first
communication gateway (X1), a 200 OK reply is received, an
acknowledgement signal is delivered, and media communication will
once again flow between X1 and H1. In this variation, the next
communication instruction is to play text-to-speech audio. The H1
will preferably call out to a TTS service to download or access the
audio, and then the H1 will stream the media to the X1 and the X1
will stream the media to the first endpoint. In an alternative
version, the H1 may instruct the X1 to perform the TTS operations
or to use a TTS service of the first region.
[0051] As shown in FIG. 10, a fourth exemplary implementation of
the system and/or method of the preferred embodiment can
accommodate a say followed by a dial. A caller form a first region
dials in and is invited to a H1 via a communication gateway X1 as
in the initial portion of method 300. Once the call has been
established, the H1 preferably downloads or accesses the
communication platform with the communication instructions. In this
particular example, the instructions include a say instruction
followed by a dial instruction. The H1 will contact a TTS server
and play the media. After the media of the TTS has completed, the
H1 will preferably continue to execute the communication
instructions and will thus execute the dial instruction. If the
dial instruction is to an endpoint in the first region, the second
endpoint will be added to the communication flow in a manner
similar to that in 300.
[0052] As shown in FIG. 11, a fifth exemplary implementation of the
system and/or method of the preferred embodiment can accommodate
hanging up a call on a detected input. In this example, the
detected input will be the DTMF input of a star (*). A user presses
star when they are ready to end a call. An RTP event is sent to the
provider service, which is then delivered to X1. X1 will initiate a
hang up of the other party. To hang up, a re-invite signal is sent
to the H1 with an action header that asks the communication
processing service to hang up the other side. The H1 then issues a
BYE sequence to the second endpoint through the X2 and continues
executing any remaining application instructions. In an alternative
implementation shown in FIG. 12, X1 delivers the RTP event to X2,
which initiates the hang up process. X2 signals the end of the call
and ends communication with the H1. H1 will then re-invite X1 or
hang up depending on the state of the communication platform.
[0053] A sixth exemplary implementation of the system and/or method
of the preferred embodiment can accommodate timeout scenarios on
the caller or callee side. Each communication gateway is preferably
responsible for detecting timeouts for their respective leg of the
communication. As shown in FIG. 13, the caller side X1 may detect a
timeout scenario when the caller endpoint stops sending RTP for a
configurable amount of time. X1 then signals the H1 to notify that
a timeout has occurred. The H1 will preferably hang up/terminate
the caller side and the callee side. The BYE signal preferably
includes a header that specifies the reason for the termination
(e.g., an RTP timeout). As shown in FIG. 14, the callee side X2 may
detect a timeout scenario when the callee endpoint stops sending
RTP for a configurable amount of time. X2 signals the error to the
H1 and the communication flow is terminated for the callee. As
there may still be application instructions that can execute for
the caller, the H1 preferably executes any remaining instructions
or alternatively terminates communication with the caller.
[0054] One or more aspects of the example embodiment can be
configured partially or entirely in a computer-readable medium
storing computer-readable instructions. The instructions are
preferably executed by computer-executable components preferably
integrated with one or more APIs, servers, routing policy servers,
POP servers, and/or communication gateways. The computer-readable
medium can be stored on any suitable computer readable media such
as RAMs, ROMs, flash memory, EEPROMs, optical devices (CD or DVD),
hard drives, floppy drives, or any suitable device. The
computer-executable component is preferably a processor but the
instructions can alternatively or additionally be executed by any
suitable dedicated hardware device.
[0055] As a person skilled in the art will recognize from the
previous detailed description and from the figures and claims,
modifications and changes can be made to the preferred embodiments
of the invention without departing from the scope of this invention
defined in the following claims.
* * * * *