VoIP Clearing & Peering

Agenda Definitions Interconnect Models and Technologies

Traditional Telephone (The early days) VoIP (What is the future?)

Summary and Conclusions

Definitions

Peering Bilateral interconnection

No Financial Implications (Bill and Keep) Settlement (Interconnect Billing)

Clearing Multilateral Interconnection

Settlement (Interconnect Billing)

Interconnect Business Model Drivers

Market Factors Fair allocation of costs (free resources get abused)

Big is better (network externalities)

Competition / RegulationTechnical Factors Route Discovery (Scalability, Bilateral vs Multi-

Lateral) Access Control Accounting

Interconnect in the Early Days

Market Factors High growth Lots of new entrants Fragmented market Highly competitive Unregulated

Interconnect Model Bill and Keep

LEC Interconnect – Bill and Keep

LocalTelco

LocalTelco

LocalTelco

$

LocalTelco

$

LEC – Bill and Keep

LECs bill their subscribers and keep all the money Interconnect trunks among LECs Simple – low overhead Works well for rural ILECs (no competition) Lack of settlement can lead to economic

distortions Does not scale

Users ModelTechnolog

y

Route Discover

yAccess Control

Accounting

LECs Bill & KeepInter-office

TrunksN Y N

The Telephone Market Matures

Bill & Keep model does not scale.

Market Consolidation. Regulation and market

stability Interconnect is managed

by a dominant inter-exchange carrier

Inter-Exchange Carrier

Inter-exchange

Carrier

LocalTelco

LocalTelco

LocalTelco

Interconnect access & billing occurs at adjacent networks

$

$

$

Inter-Exchange Carrier

IXC has Bilateral Settlement agreements with many networks

Interconnect to IXC provides global routing Tandem switch provides total call control

Access control and accounting Tandem switch creates a network bottleneck

Users Model Technology

Route Discover

yAccess Control Accounting

IXCsMulti-lateral Settlement

Tandem Switch – SS7 signaling

Y Y Y

Interconnect Future for VoIP?

Market Factors High growth Lots of new entrants Fragmented market Highly competitive Unregulated

Trend toward deregulation Natural trunking of IP mesh

different from switched star network

Interconnect Model?

ITSP – Bill and Keep

IP Network

ITSPITSP

ITSP

IP Phone

PC Phone

ENUM

$

$

DirectoryServer

RouteLook-up

ITSP – Bill and Keep

Removes network bottlenecks – enables peer to peer routing

Excellent technical solution for route discovery and scalability (DNS works!)

No access control or accounting – free resources could be abused.

Best for equal sized networks or in a regulated environment.

Users Model TechnologyRoute

DiscoveryAccess Control Accounting

Directory Svc

Free VoIP ENUM Y N N

DUNDi – Bill and Keep

$ $

DUNDi – Bill and Keep

New interconnect model being used by Asterisk users No central authority – enables peer to peer routing General Peering Agreement

Each peer has a bilateral agreement with adjacent peer GPA links all peers for global route discovery

No networks bottlenecks - Potential for high scalability No access control or accounting – free resources could

be abused.

Users Model TechnologyRoute

Discovery

Access Control

Accounting

Asterisk Bill & Keep DUNDi Y Y N

VoIP Peering

IP Network

ITSPITSP

ITSP

$

$

SBC

SBC

SBC

Interconnect access & billing occurs at Border Controllers

VoIP Peering

Bilateral agreement to peer VoIP networks Session Border Controller provides total call control

Bilateral Access control and accounting Settlement billing or Bill and Keep

Session Border Controller creates a network bottleneck

Scalability limited by bilateral agreements

Users Model TechnologyRoute

DiscoveryAccess Control

Accounting

VoIP PeeringBilateral B&K or Settlement

Session Border Controller

N Y Y

$

VoIP Clearinghouse

Certificate Authority andSettlement Clearinghouse

IP Network

ISPISP

ITSP

$

OSP

Interconnect access & billing occurs at

VoIP Domains

Route Look-up& Authorization

CDR

CDR$

VoIP Clearinghouse

Similar to ENUM - Removes network bottlenecks Excellent technical solution for route discovery and

scalability (DNS works!) Public Key Infrastructure (PKI) services ensure

secure multi-lateral peer to peer access control Standards based accounting records ensure simple,

real time settlement (no monthly CDR disputes)

Users Model TechnologyRoute

DiscoveryAccess Control

Accounting

VoIP Clearinghouse

Multi-Lateral Settlement

OSP Y Y Y

Summary of Interconnect Models

Users Model TechnologyRoute

DiscoveryAccess Control

Accounting

LECs Bill & KeepInter-office

TrunksN Y N

IXCsMulti-lateral Settlement

Tandem Switch – SS7 signaling

Y Y Y

Directory Svc Bill & Keep ENUM Y N N

ITSPs Bill & Keep DUNDi Y Y N

VoIP PeeringBilateral B&K

or Settlement

Session Border Controller

N Y Y

VoIP Clearinghouse

Multi-Lateral Settlement

OSP Y Y Y

ConclusionsReliable

Settlement

Bill & Keep

Bilateral GlobalRoute Discovery

Acc

ess

Co

ntr

ol

& A

cco

un

tin

g

Tandem Switch

ENUM

OSP

Inter-OfficeTrunks

SessionBorder

Controller

DUNDi

How Interconnect Technologies Compare