Presentation on theme: "Voice over IP Interconnect Stephen Kingham Project Manager and Consulting Engineer, Voice and Video over IP AARNet and CSIRO Ph."— Presentation transcript:
Voice over IP Interconnect Stephen Kingham Project Manager and Consulting Engineer, Voice and Video over IP AARNet and CSIRO Stephen.Kingham@csiro.au Ph +61 2 6276 6223 John Barlow Network Engineer AARNet John.Barlow@AARNet.edu.au Ph +61 2 6276 6903
Who is AARNet and CSIRO CSIRO Is Australia ’ s premier government research organisation, only partially government funded. http://www.csiro.au http://www.csiro.au AARNet Is the Australian Academic Research Network, linking Australia ’ s Universities, premier research and cultural centres to the internet. http://www.aarnet.edu.au http://www.aarnet.edu.au
AARNet VOIP Building Blocks Based on ITU H.323 standards
AARNet VoIP Service, Now Supports all telephony destinations, Toll-by-pass and feature transparency is core business. Savings range up to 90% off RRP. Traffic: connects around 16,000 telephone calls per day, and growing. Uses a root Gatekeeper and some feeders. AARNet backbone supports QoS. QoS is policed at ingress – accesslist (yuk). VoIP hackers are policed – accesslist (yuk). Billing system, based on calling IP address. QoS network management actively changes H.323 routing around problems. Test lab
Test Call Scenarios Test key call scenarios and PABX/IP Telephone alternate route under all failure conditions
AARNet VoIP, Tomorrow Research VoIP interconnects between carriers. VoIP interconnect pilots with research institutions in US, Korea, Singapore, Czech Republic, Brazil. VoIP interconnect with two Australian Carriers. Implement a smarter Gatekeeper. Get H.323 proxies working in production. Change method of policing QoS. Change method of authorising VoIP calls. Change billing system to be based on bytes rather than time (both ends pay … ). Support IP Telephones. Support VIDEO as well as audio (native as well conferencing and gateways back to ISDN).
Some key lessons Resource QoS implementation and support as much as the VoIP. Use VoIP to switch call, do not use PABXs. Reduces faults in private telephone networks. VoIP using G.729 is resilient against packet loss. Enabling QoS to get over the brief periods of congestion is needed, even on Gigabit. Billing model need to change from traditional telephony to data constructs.
Basis of the Charging Model On-net Hop-off See http://voip.aarnet.net.au/AARNethttp://voip.aarnet.net.au/AARNet
Some key lessons Although peak bandwidth per call is 24kbps, in practice it is on average 5kbps (using G.729), do your own maths on the cost! Huge changes looming for management of basic telephony. AARNet has started a working group to assist migration from PABX to IP Telephones.
VoIPMonitor TOPOLOGY Monitor links to each RNO, and Links to each member. Shutdown destinations that fail. http://lattice.aarnet.net.au/VoIPMonitor Client only tests local links
Some key issues for VoIP interconnect. H.323 proxies appear to be the answer for solving these key issues: Providing access between domains, or Internet into LAN based IP telephones. Policing use of QoS. Authenticating who is making the VoIP call. Gateways need to authenticate VoIP calls through an intelligent Gatekeeper or a clearing house sever using OSP.
VoIP Carrier Interconnection Signalling system number 7 is not appropriate for VoIP