Enterprise Video
Conferencing
When Voice Meets Video – How
SIP & H.323 Can Coexist
SIPNOC 2014
Presented by: Gernot Scheichl
Agenda
• The Market
• The Challenges
• History
• Comparing the Protocols (H.323 and SIP)
• Video Conferencing Network Designs
– Private / Public
– Traffic flows
• Conclusion
Market
• Rapid adoption
– Double digit, Y-Y growth
– Innovative applications
• Mobility • Unified communications • Cloud services• Real benefits
– Reduced costs
– Increased productivity
• Time to market advantages • Faster dispute resolution
Challenges
Seamless support of distributed users using different video clients
across different IP networks
• IP Network
– NAT/FW, QoS,
– LAN/WAN; WAN/WAN Borders
• Security
– Content and Network
• Interoperability
– Protocol and Codec
• Dial Plan
– Private and Global – Dialing Method
• Quality of experience
– Audio/Video Codec, IP QoS, Troubleshoot & Monitor
A little History
• Looking over the last 4 decades as it relates to
• Network: What Networks are used?
• Quality: Video Call Experience and Network QoS
• Security: Network / Content Security
• Protocol: Application Network Protocols
• Codec: Audio and Video
A little History 80’s and 90’s
6
• The 80’s:
• Network: public ISDN and private direct links
• Quality: good (64k-384k), little network bandwidth • Security: external encryption devices
• Protocol: H.320, V.35/X.21 • Codec: G.711 and H.261
• Dial-Plan: WorldWide (E.164) and private (direct link)
• Comment: Large equipment price drops first commercial VC-Systems
• The 90’s:
• Network: public and private ISDN, ATM, Ethernet 10Mbps hub/switched • Quality: better (64k-768k), more network bandwidth
• Security: H.325, external encryption devices
• Protocol: More H.32x (H.321, H.310 and H.323), proprietary • Codec: G.711/729 and H.261/263; mpeg2
• Dial-Plan: various, but overall E.164 based (public and private)
A little History 2000’s
• The 2000’s: “SIP - here I come”
• Network: Ethernet (IP-QoS) 10/100 Mbps switched; ISDN and ATM going away
• Quality: better, up to 1Mpbs, IP-QoS end to end challenge, higher BW at lower cost
• Security: IP network security becomes important (FW/NAT) • Protocol: H.323, SIP and some proprietary (e.g. Skype, iChat) • Codec: wideband G.722, H.264, mpeg4
• Dial-Plan: E.164 based (GDS), H.323 AnnexO (IP@extension), SIP URL • Comment: SIP finds high adoption in VoIP
H.323 Video Islands growing larger.
Global Dialing Scheme (GDS) formed (public GK with hierarchies) More “Video as a service” offerings for MCU and GW services
A little History 2010’s
8
• The 2010’s:
• Network: Ethernet (IP-QoS, 1Gbps), Wireless
• Quality: real good – 2Mbps+; HD-Video (TelePresence), IP-QoS, high BW at very low cost
• Security: network security – becoming a MUST
• Protocol: H.323, SIP and more proprietary (e.g. Facetime, google hang-out, use of WebRTC)
• Codec: narrow band codecs
• Dial-Plan: various, E.164, H.323 AnnexO, SIP URL, RealPresence • Comment:
More “Video as a service” offerings – any device to any device Video Conferencing enabled devices “everywhere”
Compare H.323 and SIP
• Standard Bodies
• H.323 – ITU (part of the H.32x umbrella)
• SIP – IETF (starting with RFC 3261)
• Elements
H.323 and SIP Elements
June 17, 2014 10
H.323 SIP Comment
Terminals (TE) User Agent (UAC / UAS) Endpoints to either create or receive messages
Gatekeeper (GK) Registrar, Proxy “SIP Server”
Endpoint registration,
authentication, address resolution, admission control, call routing Gateway Gateway Link between networks (e.g. IP to
PSTN) Multipoint Control
Unit (MCU)
Conference Bridge Multipoint conference
Border / Peer SBC / ESBC H.323: Zone/Domain mgmt and some network topology features SIP: “middle box between UA and SIP Server (topology hiding, NAT traversal)
H.323 and SIP Protocol Stack
???
H.323 and SIP Network Signaling
June 17, 2014 12
H.323 Signaling SIP Method Comment
RAS
(Registration, Admission, Status)
Register Communication between endpoint and “Server”; RAS also used to communicate between GK’ers H.225 Call Signaling Invite, ACK, Cancel, Bye, PRACK Call setup and tear down H.245 Call Control SIP SDP and Options Capability negotiation
(master/salve), codec (voice and video)
Note: This “simplified” table shows how H.323 and SIP network signaling can be compared with each other. There is no 100% match, but it does help when trying to understand enterprise video conferencing network designs. A more extensive
Network designs for H.323 and SIP
14
• Network layout and Elements
• Directory Service
• Address resolution / translation
• Protocol translation
H.323 and SIP Elements in a network
H.323 and SIP
Directory and Protocol translation?
SIP Clients
H.323 Clients H.323 and SIP
H.323 and SIP – Media Flows
H.323
Elements Elements SIP
IP -Network SIP
H.323
MCU
H.323 and SIP – Media Flows Solution
SIP Clients
H.323 Clients H.323 and SIP
Client (dual stack) H.323
Elements Elements SIP
Managed Video Conferencing
IP -Network SIP H.323 323 Elements VC-NOC SIP Elements FEATURES Account Mgmt Billing / Reporting Protocol - Translation Media Handling NAT traversal Conf. Bridge (MCU)
Security between IP Networks
H.323 and SIP Clients H.323 and SIP Clients IP Network - B IP Network - A H.323 /SIP Elements IP –Network - C H.323 /SIP Elements H.323 Border SBC/ESBC H.323 Border SBC/ESBC H.323 Border SBC/ESBC FEATURES Protocol aware Reg / Auth for remote
clients Signaling / Media Ports IP-NAT traversal FW Issues Costly additional Infrastructure Not easy to setup Troubleshooting?
Monitoring NAT/FW/Security
Bandwidth Ctrl between IP Networks
IP Network - B IP Network - A H.323 /SIP Elements IP –Network - C H.323 /SIP Elements H.323 Border SBC/ESBC FEATURES Call Admission Control CAC – BW BW reservation Traffic tagging Priority Traffic shaping Issues CAC policies Traffic tags honoring
Managed Cloud Video Conferencing
Services
Endpoints IP Network H.323 and SIP Elements VC-NOC Other Elements FEATURESConnect ANY to ANY regardless of what video endpoint you have at a nominal fee.
H.323 and SIP Elements VC-NOC Other Elements
BW issue – media flow “with other”
Outbound = 1 Inbound = 2 Outbound = 2
