U.S. patent application number 10/978824 was filed with the patent office on 2005-07-14 for method, system, and computer program product for route quality checking and management.
Invention is credited to Cheng, Anita T., Scott, Mark D..
Application Number | 20050152339 10/978824 |
Document ID | / |
Family ID | 33311130 |
Filed Date | 2005-07-14 |
United States Patent
Application |
20050152339 |
Kind Code |
A1 |
Scott, Mark D. ; et
al. |
July 14, 2005 |
Method, system, and computer program product for route quality
checking and management
Abstract
A method, system and computer program product for route checking
and management is described herein. In a voice over internet
protocol environment, the invention allows for the testing of
routes among various gateways. In an embodiment, a method for
selecting a route for a voice over IP call within a communications
network is provided. The method includes receiving a VoIP call
request from a user, identifying potential candidate routes,
assessing the quality and cost of routes and determining a route
based on cost, quality and/or user preferences.
Inventors: |
Scott, Mark D.; (Ashburn,
VA) ; Cheng, Anita T.; (Ashburn, VA) |
Correspondence
Address: |
STERNE, KESSLER, GOLDSTEIN & FOX PLLC
1100 NEW YORK AVENUE, N.W.
WASHINGTON
DC
20005
US
|
Family ID: |
33311130 |
Appl. No.: |
10/978824 |
Filed: |
November 2, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10978824 |
Nov 2, 2004 |
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09660920 |
Sep 13, 2000 |
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6816464 |
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Current U.S.
Class: |
370/352 ;
370/401 |
Current CPC
Class: |
H04L 41/142 20130101;
H04L 43/0852 20130101; H04L 41/22 20130101; H04L 43/0829 20130101;
H04L 43/50 20130101; H04L 45/70 20130101; H04L 41/5009 20130101;
H04L 43/087 20130101 |
Class at
Publication: |
370/352 ;
370/401 |
International
Class: |
H04L 012/66; H04L
012/56 |
Claims
What is claimed is:
1. A method for selecting a route for a voice over IP (VoIP) call
within a communications network, comprising: (a) receiving a VoIP
call request from a user; (b) identifying a plurality of candidate
routes to establish the VoIP call; (c) assessing each of said
candidate routes using quality measurement packets, wherein said
quality measurement packets can be used to determine at least one
route quality metric; and (d) selecting a candidate route from said
plurality of candidate routes.
2. The method of claim 1, further comprising establishing a voice
over IP (VoIP) call over the candidate route selected in step
(d).
3. The method of claim 1, wherein said communication network
comprises an Internet.
4. The method of claim 1, wherein said communication network
comprises a packet switched network and a public switched telephone
network.
5. The method of claim 4, wherein selecting a candidate route uses
as a factor locations of local exchanges within a public switched
telephone network.
6. The method of claim 4, wherein selecting a candidate route uses
as a factor whether a candidate route requires the use of a toll
call within the public switched telephone network.
7. The method of claim 1, wherein said communication network
comprises a frame relay network, an ATM network, an IP
protocol-based network, a circuit-switched network or a combination
of more than one of a frame relay network, an ATM network, an IP
protocol-based network, a circuit-switched network.
8. The method of claim 1, wherein said the candidate route is
selected on a per-call basis.
9. The method of claim 1, wherein selecting a candidate route uses
as a factor the at least one route quality metric.
10. The method of claim 1, wherein selecting a candidate routes
uses as a factor route cost and the at least one route quality
metric.
11. The method of claim 1, further comprising receiving user
preferences related to call quality and cost factors.
12. The method of claim 11, wherein selecting a candidate route
uses as a factor user preferences related to call quality and cost
and costs and quality of candidate routes.
13. The method of claim 1, wherein said at least one route quality
metric includes latency, time jitter or lost packet
information.
14. The method of claim 14, further comprising ordering the
candidate routes, wherein said ordering is based on one or more of
network addresses, route costs, general user preferences, route
quality of service and whether a route is static, wherein a static
route is one that is unchanging.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 09/660,920, filed Sep. 13, 2000, which is hereby incorporated
herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates generally to the field of voice over
Internet protocol technology. More particularly, the invention
relates to route testing and selection over packet-switched
networks.
[0004] 2. Related Art
[0005] Voice over Internet protocol (VoIP) communications services
provide telephony services over packet-switched networks, like the
Internet. In order to maintain call quality, VoIP services are
concerned with route quality. High route quality makes for more
reliable and clearer conversations. Route checking and selection
over the packet switched network (like the Internet) is necessary
to ensure quality of service.
[0006] Unlike typical data, voice data is extremely time dependent.
Transmission delays and variations in the transmission rate alter
the voice data received by the destination.
[0007] In a packet-switched network, latency and jitter are
measurable qualities of network performance. Latency is the amount
of time it takes a packet to reach its destination. Jitter is the
variation in latency. The route is the path in the network from the
origin of a packet or packets to their destination. A route can be
a direct end-to-end connection path, or it can consist of a path
linked by any number of routers, switches, gateways, gatekeepers,
etc.
[0008] Latency and jitter can degrade the communication path
between any two points on a packet-switched network, like the
Internet. In a VoIP environment, latency will be perceived by the
end users as a delay in the response of the remote site (or other
user). Furthermore, jitter is the variation in latency from one
packet to another which can be perceived as a stammering in the
conversation.
[0009] Latency and jitter each impact communication differently.
For example, if packets always arrived 50 milliseconds (ms) after
being transmitted, then there would be a 50 ms latency and no
jitter. In another example, however, if packet # 1 arrived 100 ms
after transmission, packet # 2 arrived 50 ms after transmission,
and packet # 3 arrived 150 ms after transmission, there would be an
average jitter of +/-33 ms. In VoIP applications, jitter is often
more critical than latency. Jitter can cause a packet to arrive too
late to be useful. The effect is that the packet may be delayed
enough that the end user will hear a pause in the voice that is
talking to them, which is very unnatural if it occurs during the
middle of a word or sentence.
[0010] Jitter typically occurs when the network utilization is too
high, and packets are being queued by gateways, switches, routers
or other similar devices, causing delivery times to become
unpredictable. The Internet, because of its complex structure, is
often subject to varying degrees of jitter. Jitter variation can
occur at different locations and at different times depending upon
network traffic and other conditions.
[0011] Conventional techniques can calculate the jitter and latency
present in a route. Some VoIP systems can select routes based on
the lowest jitter and/or latency. Other systems can include
management of the route selection process in response to network
conditions.
[0012] However, these techniques are not conducive to rapidly
changing network conditions and do not provide real-time route
checking and selection. Additionally, these techniques do not take
into account the costs of switching from the packet switched
network to the public switched telephone network (PSTN) in order to
maintain quality of service.
[0013] Furthermore, conventional systems do not allow calling
parties to make route selections on a per call basis.
[0014] Still further, conventional systems do not allow users to
supply their own criteria used in the checking and selection of
routes.
[0015] Therefore, in view of the above, what is needed is a system,
method and computer program product for route quality checking and
management. Further, what is needed is a system, method and
computer program product that can test and score routes on a
network based on criteria provided by a user. Such a system would
provide the optimal route for a call based on the provided
criteria. Furthermore, what is needed is a system, method and
computer program product that enables users to access the route
quality checking and management system and provide individual or
group routing preferences and/or other route information so that
the system can select the proper route for that individual or
group.
SUMMARY OF THE INVENTION
[0016] The invention is directed to a system, method and computer
program product for a route quality checking and management system
that satisfies the above-stated needs. The method of the present
invention involves a routing manager or a route management module
implemented at a gateway for determining which other gateways are
available to it. A gateway can be any server enabled for routing
voice data packets. The method involves the gateway determining the
candidate routes to the other gateways, testing those candidate
routes, determining candidate route statistics, scoring each
candidate route tested, prioritizing each scored route and storing
this priority and score information. In one embodiment, a routing
manager on a gateway tests the routes to other gateways so that it
can use the proper routes based on the preferences of users.
[0017] The method of the invention for checking a network route
includes a routing manager determining a gateway available for
routing, where the gateway is capable of responding to a request on
the communications network. The routing manager determines a
candidate route to the gateway, where the candidate route is within
the communications network.
[0018] A routing manager tests the candidate route to a gateway
using quality measurement packets, where the quality measurement
packets include route information. From the route information, the
routing manager determines route statistics, where the route
statistics are based on routing information contained within said
quality measurement packets. The routing manager score the
candidate route based on the route statistics.
[0019] In an embodiment, the method of the invention is implemented
in a communications network that includes a packet-switched
network, such as frame relay or the Internet. Furthermore, in other
embodiments, the method of the invention is implemented in a
communications network that includes a public switched telephone
network (PSTN) or a combination of a PSTN and a packet-switched
network.
[0020] The route information utilized by the invention includes the
latency, time jitter, and lost packet information.
[0021] In an embodiment, the method of the invention includes
functionality for the routing manager to prioritize the candidate
route among other tested routes based on the score obtained for
that candidate route. In other embodiments, the routing manager has
access to a database for storing score information related to the
candidate route(s) for use in route selection.
[0022] In one embodiment, the testing functions of the method of
the invention include configuring the parameters for quality
measurement packets to be sent to a gateway where the parameters
include the packet interval, packet length, number of packets, and
time limit. The routing manager includes a graphical user interface
(GUI) for configuring these parameters.
[0023] Additionally, the routing manager includes a GUI for
configuring the scoring table of the invention. Thus, the routing
manager configures the scoring table for use in scoring candidate
routes where the table includes a quality score, packet loss,
average delay, and average jitter. In other embodiments, the
routing manager includes a GUI for configuring the route ordering
applied for a gateway, where the route ordering includes file
logging information, quality of service threshold, and timeout
amount.
[0024] According to embodiments of the invention, the routing
manager forwards quality measurement packets to a gateway, where
the quality measurement packets include routing information; and
the routing manager receives returned quality measurement packets
from a gateway, where the returned quality measurement packets
include routing information.
[0025] The system and computer program product of the present
invention includes a routing manager within a gateway coupled to
both a network, such as the Internet, and the PSTN, via a local
exchange, through which users can access the gateway either over
the network or from a device connected to the local exchange. In
one embodiment, the system contains numerous modules operating
either in a redundant or distributed manner, as well as in a serial
or parallel manner. In another embodiment, the gateway includes a
database to store information collected by the routing manager.
[0026] In one embodiment of the invention, a gateway is located in
a different local exchange from other gateways to provide access to
specific geographical locations from the network. In another
embodiment, more than one gateway can be connected to any given
local exchange. In this embodiment, other gateways can prioritize
route selection based on the utilization of any one of the gateways
located in a given local exchange.
[0027] The computer program product of the present invention
further includes a graphical user interface (GUI) for entering the
specific criteria used by the method of the present invention for
checking and selecting routes.
[0028] The method of the present invention includes a route testing
routine. In one embodiment, the testing routine configures packet
parameter(s), configures a scoring table, and configures a route
order. The method of the present invention includes a testing
routine where test packet(s) are sent and received for scoring and
determination of route quality.
[0029] The route checking and management system supplies route
information that describes the route. Furthermore, the route
checking and management system includes the functionality, in
hardware or software or a combination of hardware and software, for
performing the methods described herein.
[0030] While the invention is described in terms of the above
embodiments, this is for convenience only and is not intended to
limit its application. In fact, after reading the following
description, it will be apparent to one skilled in the relevant
art(s), based on the teachings herein, how to implement the
invention in alternative embodiments (e.g., using gateways in
neighboring local exchanges, and/or stacking gateways in a single
local exchange).
[0031] Furthermore, while the following description refers to the
global Internet, it is not intended to limit the application of the
invention. It will be apparent to one skilled in the relevant art
how to implement the following invention, in any computer network,
combination of networks or other alternative embodiments. For
example, other Voice over Packet (VoP) networks include frame relay
and asynchronous transfer mode (ATM) enabled networks.
[0032] One advantage of the invention is that a user can select the
routes to other gateways to be tested.
[0033] Another advantage of the invention is that a user can select
the criteria applied to candidate routes so that the proper route
is selected.
[0034] Yet another advantage of the invention is that the system
can test routes as the call is being placed and select the best
route for that particular call. Furthermore, a user attempting to
place a call where the level of quality is below a determined level
can have the call routed to the nearest gateway with an acceptable
level of quality.
[0035] Further features and advantages of the invention as well as
the structure and operation of various embodiments of the invention
are described in detail below with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0036] The accompanying drawings, which are incorporated herein and
form a part of the specification, illustrate the invention and,
together with the description, further serve to explain the
principles of the invention and to enable a person skilled in the
pertinent art to make and use the invention.
[0037] In the drawings:
[0038] FIG. 1 is a block diagram showing an example system
architecture, according to an embodiment of the invention, showing
network connectivity among various components;
[0039] FIG. 2 is a block diagram showing an alternative example
system architecture, according to an embodiment of the invention,
showing network connectivity among the various components;
[0040] FIG. 3 is a block diagram showing a gateway that includes a
routing manager, according to an embodiment of the invention;
[0041] FIG. 4 is a flowchart illustrating a routine for determining
route quality according to an embodiment of the invention;
[0042] FIG. 5 is a flowchart illustrating a routine for candidate
route testing according to an embodiment of the invention;
[0043] FIG. 6 is an exemplary route testing configuration screen
according to an embodiment of the invention;
[0044] FIG. 7 is an exemplary route scoring configuration screen
according to an embodiment of the invention; and
[0045] FIG. 8 is an example computer system in one example
implementation of the present invention.
[0046] The invention will now be described with reference to the
accompanying drawings. In the drawings, like reference numbers
indicate identical or functionally similar elements. Additionally,
the left-most digit(s) of a reference number identifies the drawing
in which the reference number first appears.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] In summary, the routing manager of the invention connects to
other modules of the gateway to access information about other
gateways and candidate routes to those gateways. In an alternative
embodiment, the routing manager is able to perform tracing
operations to determine the candidate routes to gateways. Once
candidate routes are obtained, the routing manager tests the routes
to determine their quality of service.
[0048] Candidate routes are assigned scores (also known as a
level). The routing manager can be pre-set with various levels.
Additionally, the routing manager can be pre-set with route
ordering levels which prioritize the various aspects of a route.
These aspects can include the level assigned to a tested route, but
this is optional. In other embodiments, aspects include the address
of the destination gateway, the cost involved to route to that
gateway, etc.
[0049] In an embodiment, the routing manager provides the ordered
routes before a user places a call. In another embodiment, the
routing manager is configured to test candidate routes to a
desination gateway whenever a user requests a connection to a call
that may utilize that destination gateway.
[0050] In brief, a user of the invention is a caller known to the
VoIP system. When the system receives a call request from the user,
the system accesses user specific information (route ordering) and
the destination address (i.e., the number being called/requested)
to determine the candidate routes to use in connecting the call.
The system tests the candidate routes to ensure call quality. The
system may use route quality statistics, along with user specific
information, to determine the proper route. These and additional
embodiments and examples of the invention are now discussed in
greater detail.
[0051] FIG. 1 is a block diagram showing an example VoIP system
100, according to an embodiment of the invention, showing the
network connectivity among the various components. It should be
understood that the particular example VoIP system 100 in FIG. 1 is
shown for illustrative purposes only and does not limit the
invention.
[0052] The VoIP system 100 includes a network 102 which connects
gateways 104, 106, and 108. Network 102 is a packet-switched
network capable of serving as an intranet, internet, and/or
connecting to the global Internet. Gateways 104, 106, and 108 can
be physically located anywhere that allows connectivity with
network 102.
[0053] Each of gateways 104, 106, and 108 are connected to a local
exchange. As shown in FIG. 1, gateway 102 is connected to local
exchange 110; gateway 106 is connected to local exchange 112;
gateway 108 is connected to local exchange 114.
[0054] Local exchanges 110, 112, and 114 are each connected to the
PSTN.
[0055] Telephones 116, 118, and 120 are each connected to a local
exchange. Telephone 116 is connected to local exchange 110.
Telephone 118 is connected to local exchange 112. Telephone 120 is
connected to local exchange 114.
[0056] Telephones 116, 118, and 120 are representative of any
number of telephones connected to a given local exchange.
Typically, calls within a local exchange are toll-free or "local"
calls. Calls from a telephone in one local exchange to a telephone
in another local exchange are typically considered toll calls or
long distance calls.
[0057] FIG. 2 is a block diagram showing an example VoIP system
200, according to an alternative embodiment of the invention,
showing the network connectivity among the various components. It
should be understood that the particular example VoIP system 200 in
FIG. 2 is shown for illustrative purposes only and does not limit
the invention.
[0058] VoIP system 200 has substantially similar components to VoIP
system 100. VoIP system 200 differs from VoIP system 100 in that
gateways 204 and 206 are connected to the same local exchange,
local exchange 210. The purpose of illustrating this difference is
to illustrate a feature of embodiments of the invention. It is a
feature of the invention that routing decisions can take into
account the physical locations of local exchanges when determining
the route to use when placing a call over the VoIP systems of the
invention.
[0059] Referring to FIG. 3, a block diagram 300, according to an
embodiment of the invention, is shown.
[0060] Block diagram 300 shows a network 302 connected to gateway
304. Gateway 304 contains routing manager 306, control logic 308,
and database 310. Routing manager 306 provides route checking and
selection routines as described herein. Routing manager 306 can be
implemented in hardware or software or some combination of hardware
and software. Control logic 308 provides additional functionality
for voice coding and decoding, user logging, and other VoIP
features. Database 310 stores, among other things, the results of
route tests, route checking parameters, and route information as
described herein. Database 310 can store additional instructions
for routing manager 306 to perform.
[0061] Referring to FIG. 4, a flowchart 400 of routine for
determining route quality, according to an embodiment of the
invention, is shown.
[0062] In step 402, the routing manager 306 determines which other
gateways are available to route calls. In one embodiment, routing
manager 306 can obtain this information from database 310. In
another embodiment, a separate routing server (not shown) can
provide information about available gateways. The database 310 and
routing server are described in detail in a commonly-owned U.S.
patent application Ser. No. 09/527,920, entitled "Method, System,
and Computer Program Product for Managing Routing Servers and
Services," incorporated herein by reference in its entirety.
[0063] In step 404, the routing manager 306 determines the
candidate route(s) to the gateways that were determined in step
402. In one embodiment, candidate route(s) are determined by a
tracing operation which determines the physical network route to a
gateway. In another embodiment, database 310 provides one or more
candidate route(s) for each gateway from each other gateway.
Candidate routes can include transitions from network 102 to the
PSTN via a local exchange, such as local exchange 112. In one
embodiment, routing manager 306 determines the availability of
candidate routes to each of gateways 204, 206, and 208.
[0064] In step 406, the routing manager 306 tests the candidate
route(s) to the gateways. An embodiment of step 406 is discussed
further detail in FIG. 5. In an embodiment, routing manager 306 is
able to determine information about each gateway tested, such as,
but not limited to, the local exchange of each gateway, and
services supported by each gateway.
[0065] In step 408, the routing manager 306 determines the
candidate route statistics based on the information returned in
testing step 406. For example, routing manager 306 determines the
latency between its gateway and the other tested gateways.
Additional details and embodiments are discussed with respect to
FIG. 5.
[0066] In step 410, the routing manager 306 scores the candidate
route(s) based on the statistics determined in step 408. In one
embodiment, the routing manager 306 scores candidate route(s) based
on both the statistics determined in step 408 and stored
information from previous tests. In another embodiment, routing
manager 306 scores routes based on an averaging of the statistics
either determined or stored or a combination of both.
[0067] In step 412, the routing manager 306 prioritizes candidate
routes based on their score and the requirements of user. In one
embodiment, the candidate routes are prioritized at the time a user
places a call that utilizes a gateway.
[0068] In one embodiment, a user can prioritize routes for overall
voice quality. For example, in FIG. 2, a user can select criteria
which allows the system to select routes in conformance to those
criteria. For instance, in the case for high voice quality, routes
are selected which meet high voice quality standards, and where
such network routes are unavailable, the PSTN routes are
substituted. This routing can be more expensive than routing
entirely on network 102 because the PSTN is accessed whenever voice
quality would suffer, but such alternate routing is possible
because the user is able to select and prioritize the criteria for
their call.
[0069] In an further embodiment, gateway 104 may be in Albany,
N.Y.; gateway 108 may be in Manhattan, N.Y.; and gateway 106 may be
in Chicago, Ill. If the user is calling from a local exchange with
an orginating gateway in London, England, then the least expensive
call to Chicago, Ill. is over network 102 to gateway 106. However,
if the call quality is below a preset level, then the call is
routed alternatively. If routing to gateway 104 provides high
enough call quality, then the remainder of the call is routed over
the PSTN to local exchange 112 via local exchange 110. Therefore,
while some PSTN costs may be incurred, the overall costs are still
much lower than calling directly from London to Chicago over the
PSTN. Furthermore, voice quality is maintained.
[0070] In an alterative embodiment, gateways may be connected to
the same local exchange as other gateways, as shown in FIG. 2.
Thus, voice quality can be maintained without increases in cost by
routing to an alternative gateway in the same local exchange. This
embodiment has a further advantage of allowing for network traffic
management.
[0071] In step 414, the routing manager 306 stores the priority and
score information. In an embodiment, this information is stored in
database 310.
[0072] Referring to FIG. 5, a flowchart 500 of routine for testing
candidate routes, according to an embodiment of the invention, is
shown.
[0073] In step 502, the routing manager 306 configures the packet
parameters. In one embodiment, packets can be set to specific size.
Packets can also be sent in groups (numbers of packets). Further,
packets can be scheduled to be sent prior to a call or they can be
scheduled at regular intervals.
[0074] In step 504, the routing manager 306 configures a scoring
table. In one embodiment, a scoring table consists of heirarchical
levels assigned to specific values for the parameters being tested.
An example scoring table is shown in FIG. 7 as score table panel
708. The results (latency, jitter, etc.) of the candidate route
testing (see below) are then compared to the values assigned to the
levels of the scoring table. Candidate routes are assigned a score
based on the level that matches their results.
[0075] In step 506, the routing manager 306 configures the route
ordering. Each route is assigned a level (or score) in step 504.
The route ordering is determined by user set values, which order or
prioritize routes based on factors that include a route's level. In
one embodiment, the system can order the routes based on their
network address (IP address), cost estimate (the estimated cost for
using the route), preference (general user preference), quality of
service (the route's score), and static routes (whether the route
is static or unchanging and therefore likely to be more
reliable).
[0076] While the actual scoring and ordering of routes occurs after
the testing steps of testing step 406, the levels of routes and
route level ordering can be determined prior to actual testing.
[0077] In step 508, the routing manager 306 sends test packet(s).
In one embodiment, the routing manager 306 first creates a user
datagram protocol (UDP) socket used for sending and receiving
quality measurement packets; then automatically responds to
requests on the socket without any delay; and finally sends
messages to the corresponding socket on other gateways to measure
the quality of server to those other gateways. In the
above-described step UDP packets are used. However, as one skilled
in the relevant art will recognize other protocols can be used (for
example, TCP).
[0078] In step 510, the routing manager 306 receives returned test
packet(s). In an embodiment, the destination gateways receive a
quality measurement packet from another gateway and return a packet
back to the originating gateway as soon as possible. The returned
packet includes information about the packet that was received by
the destination gateway.
[0079] As described above, the routing manager 306 measures the
returned packets and determines a score for the route(s).
[0080] Measurement and Scoring Embodiments
[0081] In embodiments, the measurement and scoring processes of the
invention include determining the packet trip time of candidate
route, calculating the average variation in the trip time of a
measurement packet, and determining the packet loss by counting the
number of packets that were not returned. For example, table 1
shows example results from the above-described testing process.
From these results shown in Table 1, the average delay, average
jitter, and packet loss can be calculated, as shown for one
candidate route in table 2 below for the three packets shown in
table 1.
1TABLE 1 Send Receive Pkt Time Time Delay Jitter N x Y y - x
.vertline.(y - x) - (y - x)ave.vertline. 1 0 ms 45 ms 45 ms 0 ms 2
60 ms 110 ms 50 ms 5 ms 3 120 ms 160 ms 40 ms 5 ms
[0082]
2TABLE 2 Average Average Packet Delay Jitter Loss 45 ms 3 ms 0%
[0083] The packet loss percentage becomes more important even at
low levels. Five (5) per-cent packet loss may be entirely
unacceptable to a user. These figures can be used to score a
candidate route as in step 410 by assigning a score to the route
based on the results of the tests shown above. In this way, the
invention can automatically select the proper route for a call.
[0084] Furthermore, as one skilled in the relevant art(s) based on
the teachings described herein would recognize, these embodiments
can be implemented with any of the methods discussed herein, where
the routing manager of the invention is determining and/or testing
candidate routes.
[0085] The above-mentioned figures are exemplary illustrations of
features of the present invention and are not intended to limit the
present invention in any way. All the embodiments described herein
can be combined with each other to form alternative processes of
using the invention. Specifically, several features of the
invention can be implemented in combination with other features of
the invention to form further embodiments. For example, steps 508
and 510 of FIG. 5 can be repeated for each call received by the
gateway 304, while the other steps shown in FIG. 5 would only be
performed if the particular user required a modification.
[0086] Graphical User Interface
[0087] In one embodiment of the invention, the routing manager 306
provides input (GUI) screens. The gateway 304 (as shown in FIG. 3)
allows users to view and add configuration information for routing
manager 306.
[0088] As will be apparent to one skilled in the relevant art(s),
the GUI allows users of routing manager 306 to specify all inputs
(e.g., general settings, route ordering, and routing servers) and
options (e.g., packet settings, and scoring tables) described
herein.
[0089] FIGS. 6, and 7 show example interface screens of the present
invention.
[0090] These screens are exemplary and for illustrative purposes
only, as the present invention is sufficiently flexible to allow
different screen designs. It should be noted that the particular
information appearing in input screens of the routing manager 306,
result from the information entered by the user. Thus, it will be
apparent to one skilled in the relevant art(s) that the
configuration defined in steps 502, 504, and 506 utilize the
information that will be entered in the screens during operation of
the routing manager 306.
[0091] Referring to FIG. 6, a routing configuration screen 602 for
entering and modifying routing manager 306 settings is shown.
[0092] Screen 602 includes a general settings panel 604, a route
ordering panel 608, and a routing servers panel 612.
[0093] General settings panel 604 includes a change settings link
606 to add, modify, and/or delete the settings displayed in general
settings panel 604. As shown in FIG. 6, some settings are cache
timeout in seconds, dynamic routing usage, error log file name,
quality of service threshold, and quality checking usage. Cache
timeout refers to the amount of time (here set to 86,400 seconds or
24 hours) that the cache of stored candidate route scores are
stored. In other words, according to one embodiment, each candidate
route is tested once every 24 hours and given a new score. Dynamic
routing usage refers to the use of alternative routes obtains
dynamically from other gateways, as described in detail in a
previously cited, commonly-owned U.S. patent application Ser. No.
09/527,920 incorporated herein by reference in its entirety. Error
log file provides the name of a file to which error or condition
messages may be saved. Quality of service threshold refers to the
minimum value that a route can have and still be stored for use by
the system of the invention. Quality checking usage refers to
enabling the use of route quality checking. For example, according
to embodiments of the invention, route testing can be disabled, and
route ordering will still take place, albeit without the benefit of
quality of service information. These settings can be altered to
activate or deactivate the usage of route quality checking.
Additionally, a quality of service threshold can be set to
determine when route quality checking should be activated
automatically.
[0094] Route ordering panel 608 includes a change link 610 to add,
modify, and/or delete the settings displayed in route ordering
panel 608. As shown in FIG. 6, some settings are address (i.e.,
domain name or IP address), cost estimate, preference, quality of
service, and static routes (truncated in the panel's window). In
this way, a user can prioritize the parameters with which routes
are selected. In a broad application, cost estimate can be highly
prioritized to limit the range of routes includes in subsequent
selections. Quality of service can be similarly applied.
[0095] Routing servers panel 612 includes listings window 614, an
add link 616, a properties link 618 and a remove link 620. Listings
window 614 presents the entered servers and their status. In one
embodiment, these servers are used to provide candidate routes for
testing. Add link 616 allows a user to add additional servers.
Properties link 618 allows a user to configure the properties of a
server displayed in listings window 614. Remove link 620 deleted a
server from listings window 614.
[0096] Referring to FIG. 7, a quality testing configuration screen
702 for entering and modifying routing manager 306 settings is
shown.
[0097] Screen 702 includes quality checking configuration panel
704, and score table panel 708.
[0098] Quality checking configuration panel 704 includes a change
setting link 706 for modifying the packet parameters shown in panel
704. Packet parameters include, but are not limited to those shown,
such as packet interval, which is the rate at which packets are
sent, packet length, the number of packets, and the time limit over
which packets are to be sent.
[0099] Score table panel 708 includes listings window 710, add top
link 712, add after link 714, delete link 716, and modify link 718.
Links 712, 714, 716, and 718 allow a user to maintain, update and
reset the scoring levels shown in listings window 710.
Specifically, add top link 712 allows a user to add a score level
to the top of the list of score levels. Similarly, add after link
714 allows a user to add a score level below a selected score
level. In an embodiment, the scoring table is read from top to
bottom and levels assigned to candidate routes based on the first
conforming score level.
[0100] Listings windows 710 displays the parameters used to score
routes. As shown in FIG. 7, these can include average delay,
average jitter, packet loss, and quality score (some partially
truncated). The average delay, average jitter, and packet loss are
determined by the testing methods disclosed herein. For each user
defined level of average delay, average jitter and packet loss is
also assigned a quality score. The quality score is assigned to a
route that is scored as having met the other criteria entered in
listings window 710.
[0101] Description of the example screens in these terms is
provided for convenience only. It is not intended that the
invention be limited to application in these example screens. In
fact, after reading the description contained herein, it will
become apparent to a person skilled in the relevant art(s) how to
implement the invention with alternative screens.
[0102] Example Computer System
[0103] An example of a computer system 840 is shown in FIG. 8. The
computer system 840 represents any single or multi-processor
computer. In conjunction, single-threaded and multi-threaded
applications can be used. Unified or distributed memory systems can
be used.
[0104] Computer system 840 includes one or more processors, such as
processor 844. One or more processors 844 can execute software
implementing routines 300, and 400 as described above. Each
processor 844 is connected to a communication infrastructure 842
(e.g., a communications bus, cross-bar, or network). Various
software embodiments are described in terms of this exemplary
computer system. After reading this description, it will become
apparent to a person skilled in the relevant art how to implement
the invention using other computer systems and/or computer
architectures.
[0105] Computer system 840 can include a display interface 802 that
forwards graphics, text, and other data from the communication
infrastructure 842 (or from a frame buffer not shown) for display
on the display unit 830.
[0106] Computer system 840 also includes a main memory 846,
preferably random access memory (RAM), and can also include a
secondary memory 848. The secondary memory 848 can include, for
example, a hard disk drive 850 and/or a removable storage drive
852, representing a floppy disk drive, a magnetic tape drive, an
optical disk drive, etc. The removable storage drive 852 reads from
and/or writes to a removable storage unit 854 in a well known
manner. Removable storage unit 854 represents a floppy disk,
magnetic tape, optical disk, etc., which is read by and written to
by removable storage drive 852. As will be appreciated, the
removable storage unit 854 includes a computer usable storage
medium having stored therein computer software and/or data.
[0107] In alternative embodiments, secondary memory 848 may include
other similar means for allowing computer programs or other
instructions to be loaded into computer system 840. Such means can
include, for example, a removable storage unit 862 and an interface
860. Examples can include a program cartridge and cartridge
interface (such as that found in video game devices), a removable
memory chip (such as an EPROM, or PROM) and associated socket, and
other removable storage units 862 and interfaces 860 which allow
software and data to be transferred from the removable storage unit
862 to computer system 840.
[0108] Computer system 1040 can also include a communications
interface 864. Communications interface 864 allows software and
data to be transferred between computer system 840 and external
devices via communications path 866. Examples of communications
interface 864 can include a modem, a network interface (such as
Ethernet card), a communications port, etc. Software and data
transferred via communications interface 864 are in the form of
signals which can be electronic, electromagnetic, optical or other
signals capable of being received by communications interface 864,
via communications path 866. Note that communications interface 864
provides a means by which computer system 840 can interface to a
network such as the Internet.
[0109] The term "computer program product" is used to generally
refer to removable storage unit 854, a hard disk installed in hard
disk drive 850, or a carrier wave carrying software over a
communication path 866 (wireless link or cable) to communication
interface 864. A computer useable medium can include magnetic
media, optical media, or other recordable media, or media that
transmits a carrier wave or other signal. These computer program
products are means for providing software to computer system
840.
[0110] Computer programs (also called computer control logic) are
stored in main memory 846 and/or secondary memory 848. Computer
programs can also be received via communications interface 854.
Such computer programs, when executed, enable the computer system
840 to perform the features of the present invention as discussed
herein. In particular, the computer programs, when executed, enable
the processor 844 to perform the features of the present invention.
Accordingly, such computer programs represent controllers of the
computer system 840.
[0111] The present invention can be implemented as control logic in
software, firmware, hardware or any combination thereof. In an
embodiment where the invention is implemented using software, the
software may be stored in a computer program product and loaded
into computer system 840 using removable storage drive 852, hard
drive 850, or interface 860. Alternatively, the computer program
product may be downloaded to computer system 840 over
communications path 866. The control logic (software), when
executed by the one or more processors 844, causes the processor(s)
844 to perform the functions of the invention as described
herein.
[0112] In another embodiment, the invention is implemented
primarily in firmware and/or hardware using, for example, hardware
components such as application specific integrated circuits
(ASICs). Implementation of a hardware state machine so as to
perform the functions described herein will be apparent to persons
skilled in the relevant art(s).
CONCLUSION
[0113] While various embodiments of the invention have been
described above, it should be understood that they have been
presented by way of example, and not limitation. It will be
apparent to persons skilled in the relevant art that various
changes in form and detail may be made therein without departing
from the spirit and scope of the invention. This is especially true
in light of technology and terms within the relevant art(s) that
may be later developed. Thus the invention should not be limited by
any of the above-described exemplary embodiments, but should be
defined only in accordance with the following claims and their
equivalents.
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