U.S. patent application number 11/467026 was filed with the patent office on 2007-01-25 for virtual pbx based on sip and feature servers.
This patent application is currently assigned to SYMBOLIC INTELLIGENCE ENHANCED SYSTEMS, INC.. Invention is credited to Shigeaki Hakusui.
Application Number | 20070019627 11/467026 |
Document ID | / |
Family ID | 32507664 |
Filed Date | 2007-01-25 |
United States Patent
Application |
20070019627 |
Kind Code |
A1 |
Hakusui; Shigeaki |
January 25, 2007 |
Virtual PBX Based on SIP and Feature Servers
Abstract
A hierarchical internet telephony system includes a higher tier
internet telephony feature server and a plurality of lower tier
internet telephony feature servers. The higher tier internet
telephony feature server fowrards telephone calls to the lower tier
internet telephony feature servers, and each lower tier internet
telephony feature server is configurable separately from the higher
tier internet telephony feature server and from other lower tier
internet telephony feature servers to handle telephone calls
received from the higher tier internet telephony feature
server.
Inventors: |
Hakusui; Shigeaki; (Boxford,
MA) |
Correspondence
Address: |
BROMBERG & SUNSTEIN LLP
125 SUMMER STREET
BOSTON
MA
02110-1618
US
|
Assignee: |
SYMBOLIC INTELLIGENCE ENHANCED
SYSTEMS, INC.
41 Washington Street
Boxford
MA
|
Family ID: |
32507664 |
Appl. No.: |
11/467026 |
Filed: |
August 24, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10729871 |
Dec 5, 2003 |
|
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11467026 |
Aug 24, 2006 |
|
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60431038 |
Dec 5, 2002 |
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Current U.S.
Class: |
370/352 |
Current CPC
Class: |
H04M 1/006 20130101;
H04M 3/46 20130101; H04M 3/42161 20130101; H04L 65/1006 20130101;
H04M 3/20 20130101; H04M 3/42314 20130101; H04M 3/4288 20130101;
H04M 3/42127 20130101; H04M 3/54 20130101; H04M 3/465 20130101;
H04M 7/0069 20130101 |
Class at
Publication: |
370/352 |
International
Class: |
H04L 12/66 20060101
H04L012/66 |
Claims
1. A hierarchical internet telephony system comprising: a higher
tier internet telephony feature server coupled to a communication
network, the multiple user internet telephony feature server
directing telephone calls for a plurality of users; and a plurality
of lower tier internet telephony feature servers in communication
with the higher tier internet telephone feature server over the
communication network, each lower tier internet telephony feature
server directing telephone calls for an individual user, wherein
the higher tier internet telephony feature server is configurable
to direct telephone calls to the lower tier internet telephony
feature servers, and wherein each lower tier internet telephony
feature server is separately configurable to direct telephone calls
forwarded to it by the higher tier internet telephony feature
server.
2. A hierarchical internet telephony system according to claim 1,
wherein each lower tier internet telephony feature server is
configured by its respective user to operate with the higher tier
internet telephony feature server, and wherein the higher tier
internet telephony feature server is configured to either reject
telephone calls for a particular lower tier internet telephony
feature server or accept and forward telephone calls for the lower
tier internet telephony feature server.
3. A hierarchical internet telephony system according to claim 1,
wherein telephone calls are forwarded strictly according to the
hierarchy.
4. A hierarchical internet telephony system according to claim 1,
wherein telephone calls are permitted to be forwarded among peer
lower tier internet telephony feature servers.
5. A hierarchical internet telephony system according to claim 1,
wherein each internet telephony feature server comprises: a network
interface, couplable to a communication network, for sending and
receiving internet telephony signals over the communication
network; and a controller operably coupled to the network interface
for handling telephone calls received as internet telephony signals
over the network interface.
6. A hierarchical internet telephony system according to claim 5,
wherein each internet telephony feature server further comprises: a
web-based management interface, accessible through the network
interface, through which the controller can be configured.
7. A hierarchical internet telephony system according to claim 5,
wherein each lower tier internet telephony feature server further
comprises a telephone interface, couplable to a telephone device,
for sending telephone control signals to the telephone device and
receiving telephone control signals from the telephone device,
wherein the controller is operably coupled to direct telephone
calls intended for the telephone device and to manage telephone
services on behalf of the telephone device based on the telephone
control signals received from the telephone device over the
telephone interface.
8. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to ring the telephone device
over the telephone interface upon receiving a telephone call over
the network interface.
9. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to ring at least one other
telephone device over the network interface simultaneously with
ringing the telephone device over the telephone interface.
10. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to ring at least one other
telephone device over the network interface if the telephone device
is not answered within a predetermined time.
11. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to forward a telephone call
to another telephone device over the network interface in lieu of
ringing the telephone device over the telephone network upon
receiving a telephone call over the network interface.
12. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to generate a call waiting
signal to the telephone device over the telephone interface upon
receiving a telephone call over the network interface.
13. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to interrupt an existing
telephone call to the telephone device with a new telephone call
received over the network interface.
13. A hierarchical internet telephony system according to claim 7,
wherein the controller is configurable to permit one-way
communication from a new telephone call received over the network
interface to the telephone device over the telephone network.
14. A hierarchical internet telephony system according to claim 5,
wherein the controller is configurable to provide at least one of
the following services: central number and hunting assignment; call
holding; call transfer; simultaneous ring; interrupt; conference
call.
15. A hierarchical internet telephony system according to claim 5,
wherein the controller is configurable to direct telephone calls
based on time of day.
16. A hierarchical internet telephony system according to claim 5,
wherein each lower tier internet telephony feature server further
comprises at least one of a microphone and a speaker.
17. A hierarchical internet telephony system according to claim 1,
wherein each of the internet telephony feature servers operates
without assignment of an explicit global network address.
18. A hierarchical internet telephony system according to claim 1,
wherein the internet telephone feature servers intercommunicate
using a network protocol.
19. A hierarchical internet telephony system according to claim 18,
wherein the network protocol is the Internet Protocol (IP).
20. A hierarchical internet telephony system according to claim 1,
wherein at least one of the internet telephony feature servers acts
as a SIP proxy server.
21. A hierarchical internet telephony system according to claim 1,
wherein at least one of the internet telephony feature servers acts
as a SIP redirect server.
Description
PRIORITY
[0001] This patent application is a divisional of U.S. patent
application Ser. No. 10/729,871 entitled VIRTUAL PBX BASED ON SIP
AND FEATURE SERVERS filed on Dec. 3, 2003 in the name of Shigeaki
Hakusui, which claims priority from U.S. Provisional Patent
Application No. 60/431,038 entitled VIRTUAL PBX BASED ON SIP AND
FEATURE SERVERS filed Dec. 5, 2002 in the name of Shigeaki Hakusui.
The above-referenced patent applications are hereby incorporated
herein by reference in their entireties.
FIELD OF THE INVENTION
[0002] The present invention relates generally to telephonic
communications, and more particularly to a virtual PBX (Private
Branch Exchange) based on the Session Initiated Protocol (SIP) and
feature servers in a Voice-over-IP (VoIP) system.
BACKGROUND OF THE INVENTION
[0003] A Private Branch Exchange (PBX) is a subscriber-owned
telecommunications exchange that usually includes access to the
public switched telephone network (PSTN). The PBX can typically
provide various advanced telephone services, such as call hold,
call transfer, call forwarding, and conferencing, to name but a
few. PBX systems are generally costly, both for setup/maintenance
and on a per-extension basis.
[0004] A Voice-over-IP (VoIP) system is a telephonic communication
system in which telephonic communications are carried over a
communication network, such as the Internet or a private intranet,
using the Internet Protocol (IP). One advantage of a VoIP system is
that long distance phone charges can be substantially eliminated,
since long-distance voice traffic can be carried over the Internet
essentially for free. A PBX system can be used in conjunction with
a VoIP system, in which case the PBX handles telephonic
communications within the subscriber network and any voice traffic
needing to go outside of the subscriber network can be carried over
the VoIP system.
[0005] Some broadband (BB) phone services utilize the Media Gateway
Control Protocol (MGCP). It is a simple solution and firs very well
into the single home residential market with an ADSL connection,
while requiring a GIP (Global Internet Protocol) address at the
client. However, the MGCP-based BB-phone faces a formidable
challenge with Multi-dwelling Units (MDU), apartments/condominiums
and business applications. It is difficult to obtain accessibility
from the Internet to the GIP inside the LAN.
[0006] Another protocol that is often used for VoIP is the Session
Initiated Protocol (SIP). SIP is well-known in the Internet
community, and is described in the following Internet Engineering
Task Force (IETF) Request For Comments (RFC) documents, all of
which are hereby incorporated herein by reference in their
entireties:
[0007] RFC3428, Session Initiation Protocol (SIP) Extension for
Instant Messaging, B. Campbell, Ed., J. Rosenberg, H. Schulzrinne,
C. Huitema, D. Gurle, December 2002;
[0008] RFC3420, Internet Media Type message/sipfrag, R. Sparks,
November 2002;
[0009] RFC3398, Integrated Services Digital Network (ISDN) User
Part (ISUP) to Session Initiation Protocol (SIP) Mapping, G.
Camarillo, A. B. Roach, J. Peterson, L. Ong, November 2002;
[0010] RFC3372, (BCP0063), Session Initiation Protocol for
Telephones (SIP-T): (SIP-T), A. Vermuri, J. Peterson, September
2002;
[0011] RFC3361, Dynamic Host Configuration Protocol (DHCP-for-IPv4)
Option for Session Initiation Protocol (SIP) Servers, H.
Schulzrinne, August 2002;
[0012] RFC3351, User Requirements for the Session Initiation
Protocol (SIP) in Support of Deaf, Hard of Hearing and
Speech-impaired Individuals, N. Charlton, M. Gasson, G. Gybels, M.
Spanner, A. van Wijk, August 2002;
[0013] RFC3325, Private Extensions to the Session Initiation
Protocol (SIP) for Asserted Identity within Trusted Networks, C.
Jennings, J. Peterson, M. Watson, November 2002;
[0014] RFC3324, Short Term Requirements for Network Asserted
Identity, M. Watson, November 2002;
[0015] RFC3323, A Privacy Mechanism for the Session Initiation
Protocol (SIP), J. Peterson, November 2002;
[0016] RFC3312, Integration of Resource Management and Session
Initiation Protocol (SIP), G. Camarillo, Ed., W. Marshall, Ed., J.
Rosenberg, October 2002;
[0017] RFC3311, The Session Initiation Protocol (SIP) UPDATE
Method, J. Rosenberg, October 2002;
[0018] RFC3265, Session Initiation Protocol (SIP)-Specific Event
Notification, A. B. Roach, June 2002;
[0019] RFC3264, An Offer/Answer Model with Session Description
Protocol (SDP), J. Rosenberg, H. Schulzrinne, June 2002;
[0020] RFC3263, Session Initiation Protocol (SIP): Locating SIP
Servers, J. Rosenberg, H. Schulzrinne, June 2002;
[0021] RFC3262, Reliability of Provisional Responses in Session
Initiation Protocol (SIP), J. Rosenberg, H. Schulzrinne, June
2002;
[0022] RFC3261, SIP: Session Initiation Protocol, J. Rosenberg, H.
Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M.
Handley, E. Schooler, June 2002;
[0023] RFC3087, Control of Service Content using SIP Request-URI,
B. Campbell, R. Sparks, April 2001;
[0024] RFC3050, Common Gateway Interface for SIP, J. Lennox, H.
Schulzrinne, J. Rosenberg, January 2001;
[0025] RFC2976, The SIP INFO Method, S. Donovan, October 2000;
[0026] RFC2848, The PINT Service Protocol: Extensions to SIP and
SDP for IP Access to Telephone Call Services, S. Petrack, L.
Conroy, June 2000; and
[0027] RFC2806, URLs for Telephone Calls, A. Vaha-Sipila, April
2000.
[0028] Generally speaking, SIP uses proxy servers that reside
outside of the subscriber network (i.e., coupled to the Internet)
to enable telephonic communications to and from telephones within
the subscriber network. Specifically, the subscriber network
typically includes a router that interfaces the subscriber network
to the Internet. The router typically acts as a firewall to prevent
unauthorized access to the subscriber network from the Internet.
The router is configured to recognize a SIP proxy server so that
traffic from the SIP proxy server is allowed through to the
subscriber network. VoIP connections can be made to and from the
SIP phone through the SIP proxy server.
[0029] In order for a subscriber telephone to communicate over the
VoIP system, the telephone must be coupled to the router. A
traditional analog telephone can connect to the router through a
VoIP modem, which includes a standard telephone connection into
which the telephone is connected and a LAN (Local Area Network)
connector (e.g., Ethernet) for communicating with the router over a
LAN, and which performs the necessary analog-to-digital and
digital-to-analog conversions (and other functions, such as forming
packets including digitized voice data) to enable communications
over the VoIP system. VoIP phones may include the necessary
conversion logic and LAN connector for operating in the VoIP
system. For convenience, the term "SIP phone" may be used
hereinafter to refer to a VoIP phone or phone/modem combination
that can communicate over the VoIP system.
[0030] One advantage of SIP is that each SIP phone is not required
to have a global IP (GIP) address. Rather, a Distributed Host
Configuration Protocol (DHCP) server dynamically assigns IP
addresses to the SIP phones in the subscriber network, and a
Network Address Translator (NAT) performs IP address translations
between a GIP address associated with the router and the IP
addresses assigned to the individual SIP phones. The router can act
as the DHCP server and/or NAT.
[0031] SIP adds a little more complexity to the system, as it is
able to penetrate router/NAT and firewalls. Among other things,
this allows the BB-SIP-Phone to work with a PBX from the existing
LAN/Internet infrastructure in place.
[0032] An example of how a telephone connection may be established
in an SIP-based VoIP system is described with reference to FIGS.
1A-1H. FIG. 1A shows the various elements in the system, including
SIP phones 530 and 540, SIP stateful proxy servers 520 and 550, an
SIP stateless proxy server 510, and an SIP redirect server 560. In
FIG. 1B, the SIP phone 530 sends an invite to SIP proxy server 520,
which in turn sends an invite to SIP redirect server 560. In FIG.
1C, SIP redirect server 560 indicates to SIP proxy server 520 that
it has moved temporarily. In FIG. 1D, SIP proxy server 530 sends an
acknowledgement (ACK) to SIP redirect server 560 and sends a second
invite to SIP proxy server 510. In FIG. 1E, SIP proxy server 510
sends an invite to SIP proxy server 550, which in turn sends an
invite to SIP phone 540. In FIG. 1F, SIP phone 540 sends an OK to
SIP proxy server 550, which in turn sends an OK to SIP proxy server
510, which in turn sends an OK to SIP proxy server 520, which in
turn sends an OK to SIP phone 530. In FIG. 1G, SIP phone 530 sends
an ACK to SIP proxy server 520, which in turn sends an ACK to SIP
proxy server 550, which in turn sends an ACK to SIP phone 540. In
FIG. 1H, the final in-call signaling path between SIP phone 530 and
SIP phone 540 goes through SIP proxy server 520 and SIP proxy
server 550.
SUMMARY OF THE INVENTION
[0033] In accordance with one aspect of the invention, a
hierarchical internet telephony system includes a higher tier
internet telephony feature server coupled to a communication
network for directing telephone calls for a plurality of users and
a plurality of lower tier internet telephony feature servers in
communication with the higher tier internet telephone feature
server over the communication network for directing telephone calls
for an individual user. The higher tier internet telephony feature
server is configurable to direct telephone calls to the personal
internet telephony feature servers. Each lower tier internet
telephony feature server is separately configurable to direct
telephone calls forwarded to it by the higher tier internet
telephony feature server.
[0034] In various alternative embodiments, telephone calls may be
forwarded strictly according to the hierarchy or may be permitted
to be forwarded among peer lower tier internet telephony feature
servers. Each internet telephony feature server may include a
network interface for sending and receiving internet telephony
signals over a communication network and a controller for handling
telephone calls received as internet telephony signals over the
network interface. Each internet telephony feature server may also
include a web-based management interface through which the
controller can be configured. Additioinally, each lower tier
internet telephony feature server may include a telephone interface
for sending telephone control signals to a telephone device and
receiving telephone control signals from the telephone device, such
that the controller may direct telephone calls intended for the
telephone device and manage telephone services on behalf of the
telephone device based on the telephone control signals received
from the telephone device over the telephone interface. Each lower
tier internet telephony feature server may further include at least
one of a microphone and a speaker.
[0035] The controllers may be configured to perform various
services, including central number and hunting assignment, call
holding, call transfer, simultaneous ring, call interrupt, and
conference calling, to name but a few. The controllers may be
configured to direct telephone calls based on time of day. Each of
the internet telephony feature servers may operate without
assignment of an explicit global network address. The internet
telephony feature servers may intercommunicate using a network
protocol such as the Internet Protocol (IP). One or mare of the
internet telephony feature servers may act as a SIP proxy server or
a SIP redirect server.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] In the accompanying drawings:
[0037] FIGS. 1A-1H provide an example of how a telephone connection
may be established in an SIP-based VoIP system as known in the art;
embodiment of the present invention;
[0038] FIG. 2 shows an exemplary VoIP modem in accordance with an
embodiment of the present invention;
[0039] FIG. 3 shows an exemplary central line setup screen in
accordance with an embodiment of the present invention;
[0040] FIG. 4 shows an exemplary direct line setup screen and an
exemplary trust setup screen in accordance with an embodiment of
the present invention;
[0041] FIG. 5 shows an exemplary default setup screen in accordance
with an embodiment of the present invention;
[0042] FIG. 6 shows a corporate telephone system incorporating both
PBX and VoIP technologies in accordance with an embodiment of the
present invention; and
[0043] FIG. 7 shows a hierarchical telephone system in accordance
with an embodiment of the present invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0044] In embodiments of the present invention, one or mare feature
servers are used to provide advanced telephone services in an
SIP-based VoIP system. The feature server(s) can provide many, if
not all, PBX functions, as well as more advanced functions. Some
exemplary feature server functions are described below.
[0045] Each feature server typically manages telephone services for
an individual telephone number, and each feature server can operate
as a stand-alone element that is not necessarily limited to use
with a central PBX (e.g., IP-Centrex). Each subscriber can have a
personal feature server that can be configured and managed by the
subscriber and that operates independently of other feature
servers. In this respect, the feature servers are modular in that
there is no central management of the feature servers and feature
servers can be easily added and removed from the network. A network
of such modular feature servers essentially operates as a virtual
PBX, enabling each subscriber to determine how telephone calls are
handled independently of the other feature servers in the network.
The virtual PBX can therefore essentially obsolete the PBX.
[0046] The feature server(s) can be considered part of the VoIP
system in that they typically utilize IP to communicate. The
feature server(s) can reside within the subscriber network and/or
outside the subscriber network (e.g., in the Internet). The feature
server(s) can be stand-alone servers or can be multi-functional
servers (e.g., an SIP proxy server or SIP redirect server can act
as a feature server).
[0047] Some exemplary telephone services that can be provided by
the feature server(s) include:
[0048] Central number and hunting assignment.
[0049] Call holding.
[0050] Call transfer.
[0051] Simultaneous ring.
[0052] Interrupt.
[0053] Conference call.
[0054] A central number service is one in which a subscriber is
associated with a central telephone number, and the central
telephone number in turn is associated with one or more extension
telephone numbers (e.g., home phone number, work phone number, cell
phone number, alternate phone number, secretary or answering
service phone number, etc.). When the feature server receives a
call to the central telephone number, the feature server causes one
or more of the extension telephone numbers to be called. The
subscriber may specify that multiple extension telephone numbers be
called simultaneously (sometimes referred to as "simultaneous
ring"). The subscriber may specify multiple extension telephone
numbers to be called in a predetermined sequence (sometimes
referred to as "hunting"). The subscriber may specify extension
telephone numbers to be called during certain times of the day
(e.g., during business or non-business hours) or after no response
to an earlier called extension telephone number.
[0055] A call holding service is one in which the subscriber can
cause a telephone call to be placed on hold. Where the SIP phone is
a traditional analog telephone, the subscriber would typically dial
a predetermined command (e.g., "*H") on the telephone keypad. Upon
receiving the command, the feature server places the call on hold.
The subscriber may then be permitted to dial or receive another
call.
[0056] A call transfer service is one in which the subscriber can
cause a telephone call to be transferred. Where the SIP phone is a
traditional analog telephone, the subscriber would typically dial a
predetermined command (e.g., "*T") followed by the number to which
the call is to be transferred. Upon receiving the command, the
feature server transfers the call to the specified number.
[0057] A simultaneous ring service is one in which multiple
extension telephone numbers are rung essentially at the same time
when a call is received for a predetermined telephone number. An
example of this was described above with reference to central
telephone number. However, the simultaneous ring service can be
provided for any phone number. For example, the subscriber can
provide alternate telephone numbers to be called when a home phone
number or direct business phone number is called.
[0058] An interrupt service is one in which an outside party is
permitted to interrupt an ongoing telephone call to a subscriber.
This can be handled in a number of ways. For example, the call may
be placed on hold and the outside party patched into the subscriber
so that the subscriber and the outside party can communicate
exclusively, the outside party may be conferenced in so that all
three parties can communicate, or the outside party may be
permitted to speak one-way to the subscriber (e.g., whisper). The
interrupt service can be controlled by the subscriber using
commands entered through the keypad.
[0059] A conference call service is one in which multiple parties
(typically more than two, although two parties can also be
considered to be a conference) are connected.
[0060] Other types of functions can also be provided by the feature
server(s), for example, using commands entered by the subscriber
using the keypad. For example, the feature server(s) can provide
such functions as mute, last number redial, flash, voice mail.
[0061] FIG. 2 shows an exemplary VoIP modem 400 in accordance with
an embodiment of the present invention. Among other things, the
VoIP modem 400 includes a telephone interface 410 into which a
standard analog telephone 450 can be connected and a network
interface 420 (such as an Ethernet interface) for connecting to a
communication network, such as a LAN (local area network) 460. The
VoIP modem 400 may also include a microphone 430 and/or speaker
440. The microphone 430 and speaker 440 can be used to provide
speakerphone-type services. The VoIP modem 400 includes a
controller 470 implementing, among other things, a personal feature
server for managing telephone calls received over the network
interface 420 and interacting with the analog telephone 450
connected to the POTS interface 410.
[0062] The VoIP modem 400 has a number of advantages over a
traditional PBX. One advantage of the VoIP modem 400 over a
traditional PBX is that the VoIP modem 400 allows inexpensive
consumer telephones to be used, whereas the PBX typically requires
the use of more expensive business telephones that are designed for
the specific PBX. Another advantage of the VoIP modem 400 over a
traditional PBX is that the personal feature server can be managed
by the user so that changes can be made quickly and easily, whereas
the PBX is typically controlled and managed by a single person or
group (e.g., an Information Technology group of a company) and so
changes must be coordinated through that person or group. Yet
another advantage of the VoIP modem 400 over a traditional PBX is
that the VoIP modem 400 is portable, so the user can connect the
modem the network wherever it is convenient and telephone calls
will reach the modem using regular IP mechanisms. Thus, for
example, telephone calls from a work extension can continue to be
forwarded to the user when the user is away from the office or even
after the user has left the company, provided the company's feature
server is configured to forward calls for that user's extension to
the user's modem. Also, the user can be easily moved from one
office to another office while maintaining the same extension by
simply moving the modem 400, whereas the PBX must typically be
reconfigured when a user moves from one office to another office in
order for the user to keep the same extension.
[0063] When a telephone call is received over the network interface
420, the controller 470 can be configured to ring the telephone 450
via the telephone interface 410, simultaneously ring the telephone
450 via the telephone interface 410 and one or more other phone
numbers via the network interface 420, or immediately forward the
call to another telephone via the network interface 420, among
other things. If the telephone 450 is rung and is not answered
within a predetermined amount of time (or number of rings), then
the controller 470 can be configured to forward the call to another
telephone via the network interface 420. When forwarding a call,
the controller 470 can be configured to simultaneously ring one or
more other phones via the network interface 420. The controller 470
can be configured with a "chain" of telephone numbers to forward
and/or simultaneously ring. Also, when a call is received over the
network interface 420 and analog phone 450 is already in use, the
controller 470 can be configured to automatically forward the call,
generate a call waiting signal to the phone 450, interrupt the
phone 450, or permit one-way communication form the new caller to
the phone 450 (i.e., whisper), among other things. The controller
470 can receive signals from the phone 450 and perform various
advanced telephone functions (e.g., "*F" or "flash" to switch
between two or more calls, "*H" to put a call on hold, "*M" to mute
the phone, "*S" for speakerphone, "*C" for conference calling, "*X"
to transfer a call, "*V" to change handset volume, etc.).
[0064] In exemplary embodiments of the invention, the personal
feature server includes a web-based interface that is configurable
through the network interface 420. Thus, when the modem 400 is
connected to the network 460, it is easy for the user to manage and
configure the personal feature server using a traditional web
browser. Security mechanisms are preferably provided by the
personal feature server so that only the user or other authorized
persons can access the personal feature server.
[0065] FIG. 3 shows an exemplary central line setup screen 100 in
accordance with an embodiment of the present invention. When the
feature server receives a call to the central telephone number 102,
the feature server causes the extension phone numbers 104 to be
called simultaneously, except during specified non-business hours
106, in which case the non-business hours telephone number 108 is
called. If the extension phone numbers 104 are called and none are
answered within a predetermined time 109, then an alternate number
110 is called. If any other numbers are listed in 112, then those
numbers are called simultaneously. If no call is answered within a
predetermined time 114, then a last number 116 is called.
[0066] FIG. 4 shows an exemplary direct line setup screen and an
exemplary trust setup screen in accordance with an embodiment of
the present invention. This is very similar to central call setup,
except that the telephone number 202 would typically be the actual
number associated with the subscriber (e.g., home phone number or
direct work number). Again, the subscriber can specify simultaneous
ring and alternate numbers as well as the amount of time to delay
before forwarding to an alternate number. The subscriber can also
specify, for the phone number 206, a number of "whisper" numbers
204 (i.e., persons who are permitted to speak to the subscriber
when the subscriber is on a phone call) and a number of "interrupt"
numbers 208 (i.e., persons who are permitted to interrupt the
subscriber when the subscriber is on a phone call).
[0067] FIG. 5 shows an exemplary default setup screen in accordance
with an embodiment of the present invention. Here, the subscriber
can specify a default telephone number 304 to be called in case the
main number 302 is unavailable due to an Internet failure.
[0068] These set up screen shots should illustrate that a PBX is no
linger a necessity. However, this type of IP phone can work with an
existing PBX installed. Over time, this scalability will obsolete
the PBX as more and more IP phone features replace the current
PBX's features until the PBX is no longer needed.
[0069] In one exemplary embodiment of the invention, VoIP modems of
the type described above are added into corporate telephone
networks. The user generally connects the VoIP modem to the
corporate network and sets the feature server to work with the
current system. Phone calls are essentially free. Rather than
buying expensive phones for use with the PBX, the subscriber can
purchase inexpensive analog phones (or, for that matter, fancy
"designer" phones that look better than traditional business
phones). Even if the office changes its layout, or someone is
transferred to another office, the phone number would not have to
be changed. All that would need to be done is to use the VoIP
modem, access the Web, and make any necessary changes to the screen
setups (e.g., new secretary's number). The system could easily
transition exclusively to VoIP, in which case the PBX could be
eliminated.
[0070] It is preferable, although not required, for the VoIP modem
to be designed to be thin and flat, with all connectors in the back
and LEDs in the front of the unit. This way, the telephone set of a
customer's choice (any normal analog telephone would do) could sit
on top of it without taking up extra space or giving a cheap and
awkward appearance on the office desk.
[0071] In order to provide certain advanced telephone functions
using analog telephones (such as speakerphone, announce and
transfer, and hands-free answer), certain VoIP modems in accordance
with an embodiment of the present invention would include a
built-in speaker and possibly a microphone, as described above.
[0072] It is desirable for the feature servers to be available
regardless of what ISP the customer using. Therefore, the broadband
(BB) phone must work from inside routers/NAT translators and
firewalls without an explicit global IP (GIP) address assigned for
the VoIP modem.
[0073] The BB Internet Service can use any technology, including
cable modem and ADSL. For larger customers, such as corporate
users, fiber connectivity to the Internet could be used.
[0074] The feature service should be available for both residential
and corporate users. Varying the available features should
differentiate the types of service. It is scalable from residential
to corporate. For example, residential may not require central
number service.
[0075] The VoIP modem should be considered as an embodiment of the
invention in and of itself--either sold stand-alone or leased.
[0076] FIG. 6 shows a corporate telephone system incorporating both
PBX and VoIP technologies in accordance with an embodiment of the
present invention. Among other things, the telephone system
includes a corporate PBX 602 in communication with VoIP modems 608
and 610 over a LAN 604 and in communication with PBX phones 612 and
614 over a telephone network. The VoIP modems 608 and 610
preferably include personal feature servers that can be managed by
the corresponding user so that central management of the user's
specific telephone requirements is not needed. The VoIP modems 604
can be physically moved from place to place, and phone calls from
the corporate PBX 602 will be forwarded correctly without any
configuration changes to the corporate PBX 602.
[0077] FIG. 7 shows a hierarchical telephone system in accordance
with an embodiment of the present invention. Among other things,
the telephone system includes a corporate feature server 702, a
number of department feature servers 704, and, for each department
feature server 704, a number of personal VoIP modems 706 and 708.
The corporate feature server 702 can be managed by a corporate
manager and relates to the entire corporation. Telephone calls
received at the corporate feature server 702 can be forwarded to
the appropriate department feature server 704 according to the
extension requested. The department feature servers 704 can be
managed at the departmental level without impacting the corporate
feature server 702. Telephone calls received at the departmental
feature server 704 can be forwarded to a personal VoIP modem
according to the extension requested. The personal VoIP modems 706
and 708 can be managed by their respective users without impacting
the corporate or departmental feature servers. Telephone calls
received at the personal VoIP modems 706 and 708 can be forwarded
according to the rules provided by the users.
[0078] One advantage of the personal VoIP modems is that the users
can manage their own telephone environments without impacting the
corporate or department feature servers and without involving the
corporate or departmental managers. Thus, for example, if a user's
secretary is unavailable, the user can easily reconfigure his or
her personal feature server to forward calls to a different
secretary. If the user will be temporarily in a different location,
then the user can easily reconfigure his or her personal feature
server to forward or simultaneously ring to the expected location.
If the user's cell phone number changes, the user can easily
reconfigure his or her personal feature server to forward calls to
the new cell phone. If the user is expecting a telephone call from
a particular person, the user can reconfigure his or her personal
feature server to interrupt when the telephone call is received. In
the past, many of these features either were not available to
individual users or required that changes be coordinated through a
telephone system manager.
[0079] It should be noted that the term "router" is used herein to
describe a communication device that may be used in a communication
system, and should not be construed to limit the present invention
to any particular communication device type. Thus, a communication
device may include, without limitation, a bridge, router,
bridge-router (brouter), switch, node, or other communication
device.
[0080] It should also be noted that the term "packet" is used
herein to describe a communication message that may be used by a
communication device (e.g., created, transmitted, received, stored,
or processed by the communication device) or conveyed by a
communication medium, and should not be construed to limit the
present invention to any particular communication message type,
communication message format, or communication protocol. Thus, a
communication message may include, without limitation, a frame,
packet, datagram, user datagram, cell, or other type of
communication message.
[0081] The present invention may be embodied in many different
forms, including, but in no way limited to, computer program logic
for use with a processor (e.g., a microprocessor, microcontroller,
digital signal processor, or general purpose computer),
programmable logic for use with a programmable logic device (e.g.,
a Field Programmable Gate Array (FPGA) or other PLD), discrete
components, integrated circuitry (e.g., an Application Specific
Integrated Circuit (ASIC)), or any other means including any
combination thereof. In a typical embodiment of the present
invention, predominantly all of the feature server logic is
implemented as a set of computer program instructions that is
converted into a computer executable form, stored as such in a
computer readable medium, and executed by a microprocessor within
the feature server under the control of an operating system.
[0082] Computer program logic implementing all or part of the
functionality previously described herein may be embodied in
various forms, including, but in no way limited to, a source code
form, a computer executable form, and various intermediate forms
(e.g., forms generated by an assembler, compiler, linker, or
locator). Source code may include a series of computer program
instructions implemented in any of various programming languages
(e.g., an object code, an assembly language, or a high-level
language such as Fortran, C, C++, JAVA, or HTML) for use with
various operating systems or operating environments. The source
code may define and use various data structures and communication
messages. The source code may be in a computer executable form
(e.g., via an interpreter), or the source code may be converted
(e.g., via a translator, assembler, or compiler) into a computer
executable form.
[0083] The computer program may be fixed in any form (e.g., source
code form, computer executable form, or an intermediate form)
either permenently or transitorily in a tangible storage medium,
such as a semiconductor memory device (e.g., a RAM, ROM, PROM,
EEPROM, or Flash-Programmable RAM), a magnetic memory device (e.g.,
a diskette or fixed disk), an optical memory device (e.g., a
CD-ROM), a PC card (e.g., PCMCIA card), or other memory device. The
computer program may be fixed in any form in a signal that is
transmittable to a computer using any of various communication
technologies, including, but in no way limited to, analog
technologies, digital technologies, optical technologies, wireless
technologies (e.g., Bluetooth), networking technologies, and
internetworking technologies. The computer program may be
distributed in any form as a removable storage medium with
accompanying printed or electronic documentation (e.g., shrink
wrapped software), preloaded with a computer system (e.g., on
system ROM or fixed disk), or distributed from a server or
electronic bulletin board over the communication system (e.g., the
Internet or World Wide Web).
[0084] Hardware logic (including programmable logic for use with a
programmable logic device) implementing all or part of the
functionality previously described herein may be designed using
traditional manual methods, or may be designed, captured,
simulated, or documented electronically using various tools, such
as Computer Aided Design (CAD), a hardware description language
(e.g., VHDL or AHDL), or a PLD programming language (e.g., PALASM,
ABEL, or CUPL).
[0085] Programmable logic may be fixed either permanently or
transitorily in a tangible storage medium, such as a semiconductor
memory device (e.g., a RAM, ROM, PROM, EEPROM, or
Flash-Programmable RAM), a magnetic memory device (e.g., a diskette
or fixed disk), an optical memory device (e.g., a CD-ROM), or other
memory device. The programmable logic may be fixed in a signal that
is transmittable to a computer using any of various communication
technologies, including, but in no way limited to, analog
technologies, digital technologies, optical technologies, wireless
technologies (e.g., Bluetooth), networking technologies, and
internetworking technologies. The programmable logic may be
distributed as a removable storage medium with accompanying printed
or electronic documentation (e.g., shrink wrapped software),
preloaded with a computer system (e.g., on system ROM or fixed
disk), or distributed from a server or electronic bulletin board
over the communication system (e.g., the Internet or World Wide
Web).
[0086] The present invention may be embodied in other specific
forms without departing from the true scope of the invention. The
described embodiments are to be considered in all respects only as
illustrative and not restrictive.
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