14-sridhar%20ramachandran.ppt
TRANSCRIPT
Sridhar RamachandranSridhar RamachandranChief Technology OfficerChief Technology Officer
[email protected]@nextone.com
Core Session Controller
NexTone CustomersNexTone Customers
NexTone’s Session Controllers aredeployed in over 100 carrier and service provider
networks for a total capacity of over 2 BILLION minutes a month
NexTone’s Session Controllers aredeployed in over 100 carrier and service provider
networks for a total capacity of over 2 BILLION minutes a month
What is a Session Controller?What is a Session Controller?
Point of control for multimedia signaling and media− Service protection− Network isolation and insulation
Other names− IP-IP Gateway− Back to back gateway− Session Border Control− Border Session Control
Point of control for multimedia signaling and media− Service protection− Network isolation and insulation
Other names− IP-IP Gateway− Back to back gateway− Session Border Control− Border Session Control
Problems where VoIP has proven effectiveProblems where VoIP has proven effective
Transport
Switching
Interconnect− Carrier – Carrier− Enterprise – Carrier
Applications
Transport
Switching
Interconnect− Carrier – Carrier− Enterprise – Carrier
Applications
• Top and bottom line enhancing• Flexibility and enforceability are key• Control points
Growth in VoIP PeeringGrowth in VoIP Peering
ITXC Carries Record Voice Call Volumes for Holidayshttp://www.itxc.com/pages/press/release229.html
“In past years, our carrier customers used ITXC to complete their subscribers’ calls because our VoIP technology allowed us to provide them high quality at low prices. Usually, the only VoIP involved was within our network. Now carriers also choose
ITXC for interconnection because they themselves are deploying VoIP equipment in their own networks or even at their subscribers’ premises. Our technology allows these carriers to connect their VoIP networks to ours at much less cost than a
legacy PSTN interconnect and with much greater flexibility.”
In the fourth quarter of 2003, over one third of ITXC's traffic was originated or terminated through a direct VoIP interconnect between ITXC.net® and the network of another carrier. ITXC has VoIP interconnects with over 140 carriers or service providers in 60 countries and supports VoIP traffic exchange with a wide variety of network equipment vendor platforms
based on either Session Initiation Protocol (SIP) or H.323 call control protocol.
iBasis Posts Record VoIP Call Volume During New Year's Dayhttp://www.ibasis.com/news/PR2004/pr01072004.htm
"In addition to setting an overall record for traffic, we are experiencing a record volume of traffic that enters or exits the iBasis Network as IP traffic," said Ofer Gneezy, president and CEO of iBasis. "Major carriers have been deploying VoIP
infrastructure to support both retail services and direct VoIP carrier interconnects. At the same time, new service providers are delivering VoIP services directly to residential and business consumers. Both can realize significant cost efficiencies by
establishing direct VoIP interconnections with our proven global VoIP infrastructure. "More than 70% of iBasis traffic either originates or terminates through our direct VoIP interconnects with service providers. Direct VoIP interconnects require significantly less capital expense in the iBasis network than legacy TDM interconnects. In addition, we are enabling our customers to more fully benefit from the efficiencies of VoIP and the public Internet for global
telecommunications."
VoIP Peering RequirementsVoIP Peering Requirements
− Flexibility• Media and Signaling Routing based on trust boundaries• “Any-to-any” interworking – SIP, H.323, multiple vendor interoperability • High Performance and Scale• “On-demand” Media Processing
− Leverage and enforce existing peering agreements• Call Admission Control
Prevent Denial of Service attacks and service abuse/theft• Call accounting
Call Detail Record (CDR) generation and reporting• Topology Hiding
Go across address boundaries− Control Points
• Segmentation/classification of traffic
− Flexibility• Media and Signaling Routing based on trust boundaries• “Any-to-any” interworking – SIP, H.323, multiple vendor interoperability • High Performance and Scale• “On-demand” Media Processing
− Leverage and enforce existing peering agreements• Call Admission Control
Prevent Denial of Service attacks and service abuse/theft• Call accounting
Call Detail Record (CDR) generation and reporting• Topology Hiding
Go across address boundaries− Control Points
• Segmentation/classification of traffic
What are Carriers’ session control needs?What are Carriers’ session control needs?
Call routing with multiple business models:− Wholesale− Transit− Pre-paid− Post-paid/retail
Service brokerageSpecial applications− Permissive dialing
Call routing with multiple business models:− Wholesale− Transit− Pre-paid− Post-paid/retail
Service brokerageSpecial applications− Permissive dialing
Edge SCEdge SC
Session Controller PlacementSession Controller Placement
SIP Network
EnterprisePeering
EnterprisePeering
PSTN
BroadbandH.323 Network
CarrierPeeringCarrierPeering
BroadbandNAT Traversal
BroadbandNAT Traversal
PSTNOrig/Term
PSTNOrig/Term
Edge SCEdge SC
Softswitch
Core SCCore SC
Edge SCEdge SC
AggregationAggregation
Multiple interconnects between same carriersMulti-stage and hierarchical call admission controlCore SC maintains notion of aggregate capacity
Multiple interconnects between same carriersMulti-stage and hierarchical call admission controlCore SC maintains notion of aggregate capacity
Partner CarrierIP Network
CarrierIP
Network
Edge SCCore SC
Edge SC
Merits of this ApproachMerits of this Approach
No “control” protocolCall admission control based on network egress policiesAbility to add other service selection logic− Applications− Quality of Service demanded or provisioned
Call routing with mixed business models− Wholesale− Pre-paid or post-paid− Transit
Normalized and vendor independent call routing− SIP only
No “control” protocolCall admission control based on network egress policiesAbility to add other service selection logic− Applications− Quality of Service demanded or provisioned
Call routing with mixed business models− Wholesale− Pre-paid or post-paid− Transit
Normalized and vendor independent call routing− SIP only
Other AdvantagesOther Advantages
Implementation flexibility− Redirect server− Stateful SIP proxy− B2BUA
Core SC function can be integrated into Edge SCLeverage TRIP (rfc 3219) and TGREPView Edge SCs and Gateways as originators and terminators of sessions
Implementation flexibility− Redirect server− Stateful SIP proxy− B2BUA
Core SC function can be integrated into Edge SCLeverage TRIP (rfc 3219) and TGREPView Edge SCs and Gateways as originators and terminators of sessions
What about the “Softswitch”?What about the “Softswitch”?
“Control” paradigm has limited effectiveness− Gateway control− Call control
Softswitch designed for a “closed” network− MGCP/MEGACO to provide total control of internal network
How does one build a fabric of softswitches?
“Control” paradigm has limited effectiveness− Gateway control− Call control
Softswitch designed for a “closed” network− MGCP/MEGACO to provide total control of internal network
How does one build a fabric of softswitches?
SummarySummary
Session Controllers are essential for VoIP peeringCore Session Controllers provide higher level functionality, based on SIP signaling
Session Controllers are essential for VoIP peeringCore Session Controllers provide higher level functionality, based on SIP signaling
What about the “Softswitch”?What about the “Softswitch”?
“Control” paradigm has not proven effectiveSoftswitch designed for a “closed” network− MGCP/MEGACO to provide total control of internal network
VoIP interconnects challenge the Softswitch “control” paradigm− Interconnects = carrier peering, and MGCP/MEGACO “control” of 3rd party
networks not viable− SIP/H323 typically added as after-thought to interwork trusted devices
Softswitch domains (and VoIP interconnects should never be trusted)VoIP Interconnect Solution:− Keep SS7 and MGs at the edge of the VoIP network, Softswitch as “cluster
controller” to help handle SS7/C7− Introduce Session Controllers to manage VoIP peering and interconnects
between carriers and enterprises− Overcome lower layer (Layer 2/3) IP issues call-by-call – NAT/PAT, security,
VLANs etc
“Control” paradigm has not proven effectiveSoftswitch designed for a “closed” network− MGCP/MEGACO to provide total control of internal network
VoIP interconnects challenge the Softswitch “control” paradigm− Interconnects = carrier peering, and MGCP/MEGACO “control” of 3rd party
networks not viable− SIP/H323 typically added as after-thought to interwork trusted devices
Softswitch domains (and VoIP interconnects should never be trusted)VoIP Interconnect Solution:− Keep SS7 and MGs at the edge of the VoIP network, Softswitch as “cluster
controller” to help handle SS7/C7− Introduce Session Controllers to manage VoIP peering and interconnects
between carriers and enterprises− Overcome lower layer (Layer 2/3) IP issues call-by-call – NAT/PAT, security,
VLANs etc
Core Session ControllerCore Session Controller
IntroductionWhat is a session controller?Growth in VoIP peeringNeed for more control at the coreView of softswitchCore session controller fabric
IntroductionWhat is a session controller?Growth in VoIP peeringNeed for more control at the coreView of softswitchCore session controller fabric