Multiplex communications – Pathfinding or routing – Combined circuit switching and packet switching
Reexamination Certificate
1996-10-10
2001-05-29
Patel, Ajit (Department: 2661)
Multiplex communications
Pathfinding or routing
Combined circuit switching and packet switching
C370S401000, C370S463000, C370S476000
Reexamination Certificate
active
06240084
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates generally to transferring data packets between a telephony endpoint and a wide or local area network and more particularly to a secondary bus provided in a personal computer (PC) server-based platform for increasing the capacity for processing and transferring voice data.
Referring to
FIG. 1
, a conventional PC host platform
12
includes a PC host motherboard
22
coupled through a PC backplane such as a PCI or ISA bus
20
to various peripheral cards
24
. Commercially available Internet-based packet-voice products are referred to generally as telephony endpoint cards
16
. The packet-voice products
16
are used to convert analog voice signals from a telephone line
18
to digital data. A number of existing PC-based voice products are based on either ISA or PCI bus telephony cards which connect to the PC backplane bus
20
and interconnect through a TDM bus such as the Dialogic SC bus.
A router card
14
includes a local area network (LAN) interface and a wide area network (WAN) interface for coupling the PC host
22
to different network systems. The telephony cards
16
currently provide no direct Internet Protocol (IP) packet handling or routing functions, and rely on the PC host
22
for performing all packet processing. After the packet processing of the voice data is completed by the PC host
22
, the voice packet data is transferred over a LAN or WAN system through router card
14
.
One of the principle problems with PC-based packet handling is timely delivery of delay-sensitive voice traffic. In a PC, the simplest solution is to transfer all of the data from the voice endpoint cards
16
across the ISA or PCI bus
20
to a main processor on the PC host motherboard
22
. Significant latencies exist in the voice card/host bus transfer, interrupt service and application scheduling, packet treatment logic (e.g., real-time transport protocol (RTP) packetization), transfer through the host computer stack and host processor/NIC bus transfer.
While manageable in internet phone terminals, latencies do not scale well to servers with tens or hundreds of endpoints. Since the host CPU in motherboard
22
and the PC backplane bus
20
are shared resources, performance is throttled for high-end routing applications.
Accordingly, a need remains for improving performance of telephony data handling in PC-based server platforms.
SUMMARY OF THE INVENTION
A PC-based server platform includes one or more telephony endpoint cards that receive and transmit analog telephony data through a telephone line. A router card in the server platform is coupled to different network systems such as an IP-based Wide Area Network (WAN) and a Local Area Network (LAN). The router card and the telephone endpoint card are coupled together with a TDM bus that operates independently from a PC backplane bus normally used for processing and transferring telephony data to various network systems.
The TDM bus transfers telephony data between different network systems and the telephony endpoint cards independently of the host system and the host system backplane bus. The network endpoint is moved onto the same bus as the telephony endpoint cards, eliminating high-volume voice data transfers across a conventional shared PC backplane, such as an ISA or PCI bus.
By eliminating involvement of the PC host in voice packet handling, many of the latencies in current PC server based telephony network communication are eliminated or reduced. The system also has greater configuration flexibility, performance, and scalability than either a combined router/telephony endpoint or a server-based routing design. The router is also used as a standard LAN interface when transferring data packets between a LAN system and the PC host system.
A DSP voice processing card is coupled between the backplane bus and the TDM bus. The DSP compresses and decompresses data transferred between the network systems and the telephony cards. The DSP increases the capacity of the telephony endpoint cards for processing telephony data.
The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention which proceeds with reference to the accompanying drawings.
REFERENCES:
patent: 4523055 (1985-06-01), Hohl et al.
patent: 4535448 (1985-08-01), Baxter et al.
patent: 4644532 (1987-02-01), George et al.
patent: 4740955 (1988-04-01), Litterer et al.
patent: 4771425 (1988-09-01), Baran et al.
patent: 4811339 (1989-03-01), Bouillot et al.
patent: 4819228 (1989-04-01), Baran et al.
patent: 4879551 (1989-11-01), Georgiou et al.
patent: 4903261 (1990-02-01), Baran et al.
patent: 4962532 (1990-10-01), Kasiraj et al.
patent: 4970678 (1990-11-01), Sladowski et al.
patent: 4991169 (1991-02-01), Davis et al.
patent: 5020058 (1991-05-01), Holden et al.
patent: 5059925 (1991-10-01), Weisbloom
patent: 5072449 (1991-12-01), Enns et al.
patent: 5088032 (1992-02-01), Bosack
patent: 5115431 (1992-05-01), Williams et al.
patent: 5121390 (1992-06-01), Farrell et al.
patent: 5128945 (1992-07-01), Enns et al.
patent: 5224099 (1993-06-01), Corbalis et al.
patent: 5243342 (1993-09-01), Kattemalalavadi et al.
patent: 5255291 (1993-10-01), Holden et al.
patent: 5268592 (1993-12-01), Bellamy et al.
patent: 5274631 (1993-12-01), Bhardwaj
patent: 5274635 (1993-12-01), Rahman et al.
patent: 5274643 (1993-12-01), Fisk
patent: 5280480 (1994-01-01), Pitt et al.
patent: 5280500 (1994-01-01), Mazzola et al.
patent: 5313454 (1994-05-01), Bustini et al.
patent: 5317562 (1994-05-01), Nardin et al.
patent: 5321350 (1994-06-01), Haas
patent: 5327421 (1994-07-01), Hiller et al.
patent: 5345445 (1994-09-01), Hiller et al.
patent: 5345446 (1994-09-01), Hiller et al.
patent: 5359592 (1994-10-01), Corbalis et al.
patent: 5365524 (1994-11-01), Hiller et al.
patent: 5386567 (1995-01-01), Lien et al.
patent: 5390175 (1995-02-01), Hiller et al.
patent: 5394394 (1995-02-01), Crowther et al.
patent: 5422880 (1995-06-01), Heitkamp et al.
patent: 5430715 (1995-07-01), Corbalis et al.
patent: 5473599 (1995-12-01), Li et al.
patent: 5473607 (1995-12-01), Hausman et al.
patent: 5491687 (1996-02-01), Christensen et al.
patent: 5491804 (1996-02-01), Jeath et al.
patent: 5509006 (1996-04-01), Wilford et al.
patent: 5517185 (1996-05-01), Acimovic et al.
patent: 5519704 (1996-05-01), Farinacci et al.
patent: 5561669 (1996-10-01), Lenney et al.
patent: 5699413 (1997-12-01), Sridhar
patent: 5742596 (1998-04-01), Baratz et al.
patent: 5802546 (1998-09-01), Chisholm et al.
patent: 5828846 (1998-10-01), Kirby et al.
FitzGerald Cary W.
Knappe Michael E.
Oran David R.
Cisco Systems Inc.
Marger Johnson & McCollom PC
Patel Ajit
Phunkulh Bob A.
LandOfFree
Telephony-enabled network processing device with separate... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Telephony-enabled network processing device with separate..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Telephony-enabled network processing device with separate... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2480321