Voice over IP (VoIP) Expert
Dr. Lavian is a Voice over IP (VoIP) expert who offers expert consulting services and patent analysis involving VoIP, SIP, and streaming media. VoIP is one of the fastest-growing segments of the telecommunications expert witness and internet expert witness industry. As VoIP technologies grow, service providers want to implement turnkey solutions with robust management interfaces and cloud-based functionality.
Voice over IP (VoIP), the acronym for voice over Internet Protocol (IP), is a way to directly transmit voice or other audio information via IP networks, bypassing traditional telephone carrier networks. VoIP Technologies integrate with conventional PSTN infrastructures, devices, and protocols based on developments in SIP/RTP technologies and deploy upon wireless or fixed data networks.
These technologies and protocols democratize communications in the workspace and at home, allowing anyone to engage in real-time communication regardless of location, including streaming media and video conferencing.
Underlying transport and control protocols typically include SIP, RTP (RTP/UDP), MGCP, H.323, and its extension, WebRTC, etc. VoIP projects often include the integration of VoIP (Voice over IP) and streaming media with SIP (Session Initiation Protocol), Internet protocols (TCP/IP), and the traditional Public Switched Telephone Network (PSTN). The VoIP system is utilized as the backbone of unified communications systems.
VoIP technologies are usually deployed in business processes, especially e-commerce and business continuity. VoIP technologies are built on SIP (Session Initiation Protocol) over Real-time Transport Protocol (RTP) and other Internet protocols (TCP/IP). Some deployments include handset integration with text messaging capabilities over SMS or MMS, Instant Messaging (IM), and chat applications. VoIP technologies encompass any media streaming technology, system, method, or application that utilizes VoIP application layer protocols.
Dr. Lavian has worked with VoIP systems and protocols, audio/video conferencing, and streaming technologies, primarily as implemented through the TCP/IP protocol suite. His work covers VoIP systems at every layer — application, transport, network, data link, and physical. He has worked with the Internet protocol suite (TCP/IP) and networking and communications technologies, including:
VoIP Technologies
The following are Dr. Tal Lavian’s areas of expertise in VoIP:
- Voice over IP (VoIP) expert consulting in Multimedia, audio, and video streaming, video/audio conferencing, streaming media, and music streaming over TCP/IP protocol stack using standard Internet protocols such as TCP, UDP, IP, HTTP, HTML, and Web services.
- Integration of VoIP and streaming media with SIP, Internet protocols (TCP/IP), PSTN, and VoIP systems as the backbone of unified communicants.
- Integration of such protocols and services with short message technologies, including text messaging, SMS, MMS, Instant Messaging (IM), and chat applications.
- Implementing such technologies over handsets, mobile devices, smartphones, cellular networks, wireless technologies, architectures, standards, systems, and backend infrastructure.
- Streaming protocols, VoIP protocols, IP telephony, SIP, RTP, H.323, MGCP, and codecs.
- Bandwidth, Quality of Service (QoS) as related to conferencing and media streaming
- PSTN, SS7, POTS, Pulse Dialing and DTMF.
- RTP, RTCP, H.323, and SIP.
- VoIP Gateways, Gatekeepers, and Terminals.
Background
Dr. Lavian holds a Ph.D. in Computer Science from UC Berkeley, specializing in network communications, and spent nearly 20 years researching, studying, and lecturing at UC Berkeley. He served as Principal Scientist and Principal Architect at Nortel Networks (1996–2007), developing voice and data systems, and as a DARPA Principal Investigator. Dr. Lavian has over 120 patents covering VoIP and communications systems, over 25 scientific publications, and has been retained in over 70 cases, including 80+ depositions, before U.S. federal courts, PTAB, ITC, and international tribunals. His VoIP case work includes Apple v. VoIP-Pal.com (U.S. Patent Nos. 9,537,762 and 9,813,330, involving VoIP call routing and processing), Polycom v. Direct Packet Research (U.S. Patent Nos. 7,710,978 and 8,560,828, involving VoIP conferencing technologies), and Canada Revenue Services v. Iris Technologies (involving VoIP technologies and CDR analysis).
VoIP Protocols
Numerous VoIP protocols exist, including two of the leading standard-based protocols. Each approach involves the use of multiple protocols. The main difference between one VoIP configuration and another is signaling protocols. RTP and RTCP are the media protocols. Various codecs are also utilized in conjunction with different VoIP technology approaches.
VoIP Network Components
Dr. Lavian’s expertise covers VoIP network components including gatekeepers (admission control, address resolution), gateways (protocol translation via Media Gateway Controllers and Media Gateways), SIP proxies, session border controllers, and IP-PBX systems.
Frequently Asked Questions
What VoIP protocols and technologies is Dr. Lavian expert in?
Dr. Lavian provides expert analysis on SIP (Session Initiation Protocol), RTP (Real-time Transport Protocol), H.323, SRTP, voice codecs, unified communications platforms, and IP-PBX systems — all common technology areas in VoIP patent disputes.
Can Dr. Lavian serve as a VoIP expert witness in PTAB IPR proceedings?
Yes. Dr. Lavian has provided testimony in USPTO Patent Trial and Appeal Board (PTAB) IPR proceedings involving VoIP and communications technologies, including submission of expert declarations and deposition testimony.
What VoIP companies has Dr. Lavian consulted for?
Dr. Lavian has consulted in cases involving technology companies including Avaya, Cisco Systems, Polycom, and other telecommunications and VoIP platform providers.
How does VoIP expertise apply to patent infringement analysis?
VoIP patent cases require an expert who can analyze SIP signaling flows, RTP media streams, voice codec implementations, call routing logic, and quality of service mechanisms at the protocol level. Dr. Lavian provides claim construction, infringement analysis, and validity opinions on VoIP patents in federal court and PTAB proceedings.
What is Dr. Lavian’s background in voice communications technology?
Dr. Lavian holds a Ph.D. from UC Berkeley, specializing in telecommunications, network communication, and Internet technologies. He has 120+ patents covering VoIP and communications systems, nearly 20 years of industry experience at Nortel Networks developing voice and data systems, and 70+ case engagements.
Can Dr. Lavian testify on unified communications and WebRTC patents?
Yes. Dr. Lavian’s expertise extends beyond traditional VoIP to include unified communications platforms, WebRTC browser-based communications, SIP trunking, video conferencing integration, and cloud-based communications services — all common subjects in modern VoIP patent disputes.
For inquiries, contact Dr. Lavian at +1 (408) 209-9112 or via the contact page.