12 january 2006 cdg conference call integrating existing number portability solutions in...
TRANSCRIPT
12 January 2006
CDG Conference Call
Integrating Existing Number Portability Solutions in Carrier-ENUMDouglas Ranalli, NetNumber, Inc.
2
About NetNumber
• Provider of next generation addressing solutions to carriers and operators based on the NetNumber TITAN platform.– Transactional IP-Telephony Addressing & Numbering (TITAN)
• Common transaction platform in operator’s network for both SS7/C7 and IP Addressing:– Number-Portability, Flexible-Numbering (GTT), etc:
• Multiple protocols: – AIN 0.2, PCS-1900, GSM/MAP, IS-41, INAP, DNS, SIP and ENUM.
• Multiple interfaces:– T1/E1 low-speed link, SIGTRAN and IP.
– Carrier-ENUM: Flexible implementation options for the discovery of carrier-controlled IP-services.
• ENUM query:– Different address resolution models can be configured on a country-by-country
basis. – Up to 43,000 transactions/second on a single TITAN Edge server.
• SIP Invite with 302 redirect:– SIP Invite to a TEL URI results in a SIP 302 “temporarily moved” response with one
or more SIP URIs as contact addresses. – Up to 15,000 transactions/second on a single TITAN Edge server.
4
Carrier-ENUM Background
• Private service discovery infrastructure.• Accessed by all types of carriers.• Common domain name: “e164enum.net”• Standard query/response protocol as defined
by RFC 3761.• Supports number-portability.
• Focus of this presentation:– Carrier-ENUM implementation models that leverage existing
number-portability solutions.
5
IMS ENUM Call-Flow Example
1. End-user dials E.164 to initiate service.
2. S-CSCF issues ENUM service discovery query to on-site or hosted ENUM server for a SIP-URI.
3. S-CSCF resolves host name within SIP URI using on-site or hosted private DNS infrastructure.
4. S-CSCF sends SIP Invite to destination I-CSCF.
5. I-CSCF queries HSS to get address of S-CSCF.
6. I-CSCF proxies Invite to destination S-CSCF.
7. Standard SIP/SDP session negotiation follows.
Orig.S/W
S-CSCF
OSS
InternalNAPTR
2
Originating Carrier
ENUMServer
DNSServer
Destination Carrier
S-CSCF
Dest.S/W
7
4
3
1
I-CS
CF
HSS
5
6
6
ENUM Implementation Options
• DNS Delegation– ENUM service discovery via DNS delegation through Tier-0,
Tier-1, Tier-2 infrastructure.
• Central Portability Database– Central portability database fulfills role of Tier-0 and Tier-1 for a
given country.• Solution utilized by GSM, CDMA and GRX/CRX interconnect
providers in North America today.
• Number-Block Assignment– Existing number-block assignment data fulfills the role of Tier-0
and Tier-1 for any non-ported network. • Simple extension of model being used in North America today.
• IMSI Query– MAP query for IMSI address fulfills the role of Tier-0 and Tier-1
for any carrier/operator that supports IMSI addressing.• Solution being used by GSM operators in Europe today to
interconnect MMS.
7
DNS Delegation
Orig.S/W
S-CSCF
OSS
InternalNAPTR
2
Originating Carrier
ENUMServer
DNSServer
Tier-0Tier-1
Destination Carrier
Tier-2ENUM
S-CSCF
Dest.S/W
2a
2b
7
4
3
1
I-CS
CF
HSS
5
6
2. S-CSCF issues ENUM service discovery query to on-site or hosted ENUM server for a SIP-URI.
a. ENUM Server queries Tier-0 to identify a country-specific Tier-1 then queries the Tier-1 to identify the destination operator (NS record of operator’s Tier-2 name server).
b. ENUM server queries the destination Tier-2 nameserver to get a NAPTR record identifying an appropriate network entry-point (I-CSCF address) in the form of a SIP URI.
8
Central Portability Database
Administrator
InterconnectNAPTR Portability
Data
Orig.S/W
S-CSCF
OSS
InternalNAPTR
2
8
Originating Carrier
ENUMServer
DNSServer
Destination Carrier
S-CSCF
Dest.S/W
7
4
3
1
I-CS
CF
HSS
5
6
2. S-CSCF issues ENUM service discovery query to on-site or hosted ENUM server for a SIP-URI.
• ENUM Server checks for locally provisioned portability data to identify the destination operator then checks for locally provisioned interconnect data to discover an appropriate I-CSCF address (or NS record) for the destination operator.
Key Benefits: • Resolution is extremely fast. No Tier-1 or Tier-2 wide area network queries required.• Originating operator can locally provision an appropriate interconnect address for a
destination partner.
9
Number-Block Assignment
Administrator
InterconnectNAPTR Number
BlockData
Orig.S/W
S-CSCF
OSS
InternalNAPTR
2
8
Originating Carrier
ENUMServer
DNSServer
Destination Carrier
S-CSCF
Dest.S/W
7
4
3
1
I-CS
CF
HSS
5
6
2. S-CSCF issues ENUM service discovery query to on-site or hosted ENUM server for a SIP-URI.
• ENUM Server checks for locally provisioned number-block assignment data to identify the destination operator then checks for locally provisioned interconnect data to discover an appropriate I-CSCF address (or NS record) for the destination operator.
Key Benefits: • Resolution is extremely fast. No Tier-1 or Tier-2 wide area network queries required.• Originating operator can locally provision an appropriate interconnect address for a
destination partner.
10
IMSI Query
Orig.S/W
S-CSCF
OSS
InternalNAPTR
2
Originating Carrier
ENUMServer
DNSServer
Destination Carrier
HLR
S-CSCF
Dest.S/W
2a
7
4
3
1
I-CS
CF
HSS
5
6
STP
MAP"SRI_for_SM"
Administrator
InterconnectNAPTR
2. S-CSCF issues ENUM service discovery query to on-site or hosted ENUM server for a SIP-URI.
• ENUM server issues MAP query for an IMSI address to identify the destination operator then checks for a locally provisioned I-CSCF address (or NS record) for the destination operator.
Key Benefits: • Leverages existing operator investment in IMSI addressing to fulfill Tier-0 and Tier-1 function. • Originating operator can locally provision an appropriate interconnect address for a
destination partner. • Solution already being used to interconnect MMS services today.
11
Recommendation
• Document multiple options for integrating existing number-portability solutions in Carrier-ENUM.– Operators and GRX/CRX/IPX providers will benefit from
flexibility.• Various Carrier-ENUM implementations work equally well in on-
site or hosted ENUM server deployments. • Different solutions can be applied to different country-codes.
– Solutions can be enhanced by use of third-party interconnect registries.
• Multiple interconnect registries available today or under development.
• Interconnect registries facilitate the exchange of appropriate interconnect data (points of interconnect) between carriers/operators.
– Eliminate requirement for manual entry of interconnect data.– More sophisticated than wide-area-network query to a Tier-2
nameserver.» Different interconnect addresses for different partners.