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  1. 1. Voice Peering Implementing a Global Architecture for Interconnection 6th Annual Global VoIP Services Budapest, 13th March 2007 Richard Stastny, ÖFEG* * The opinions expressed here may or may not be that of my company
  2. 2. VoIP <ul><li>Most service providers (telco‘s and others, also enterprises) are currently looking to implement VoIP in their networks and to migrate from PSTN to VoIP </li></ul><ul><li>in 2009 VoIP will account for 90% of the market </li></ul><ul><li>between 2010 and 2015 most telcos are planning to switch off their PSTN </li></ul><ul><li>but it is one thing to provide a VoIP solution within the own network (adminstrative domain) </li></ul><ul><li>and another to interconnect with other service providers </li></ul><ul><li>using the PSTN is not an option </li></ul>
  3. 3. VoIP Peering – IP Interconnect <ul><li>IP based Interconnection between different Administrative Domains </li></ul><ul><ul><li>on behalf of end-users </li></ul></ul><ul><li>including Realtime Multimedia Services </li></ul><ul><li>using Public User Identities </li></ul><ul><ul><li>dial strings </li></ul></ul><ul><ul><li>E.164 Numbers </li></ul></ul><ul><ul><li>SIP Address-of-Records (kind of SIP URI) </li></ul></ul>
  4. 4. The Use Cases of VoIP Peering AD A AD B AD C Gateway PSTN ENUM Internet DNS
  5. 5. Numbering/Naming/Address/ Routing Resolution Process Dialed Digits Name to Address Translation Route Determination Dial string Target Name (TEL, URN) Target Address (SIP URI) Dial Plan Number Plan Translation Service ( ENUM , LoST, etc.) Routing Tables (DNS, LoST, configured, ) E.164 SIP URI
  6. 6. Standardisation in IETF <ul><li>Two major developments in IETF regarding (VoIP) Interconnect: </li></ul><ul><li>ENUM WG extended scope to include Infrastructure ENUM </li></ul><ul><li>Session PEERing for Multimedia INTerconnect </li></ul><ul><ul><li>WG established 8. February 2006 </li></ul></ul>
  7. 7. Separation of Scope <ul><li>The ENUM WG is primarily concerned with the acquisition of a Target Address (e.g. a SIP URI) from a Target Name , </li></ul><ul><li>while the SPEERMINT WG is focused on the use of such Target Addresses . </li></ul><ul><li>Importantly, the target addresses used in SPEERMINT can be derived from ENUM (i.e., an E.164 DNS entry), or via any other mechanism available. </li></ul>
  8. 8. Numbering/Naming/Address/ Routing Resolution Process Dialed Digits Name to Address Translation Route Determination Dial string Target Name (TEL, URN) Target Address (SIP URI) Dial Plan Number Plan Translation Service ( ENUM , LoST, etc.) Routing Tables (DNS, LoST, configured, ) E.164 SIP URI SPEERMINT ENUM
  9. 9. <ul><li>Electronic or E.164 NUMber mapping is defined by the Internet Engineering Task Force (IETF) in RFC3761 as: </li></ul><ul><li>the mapping of „Telephone Numbers“ to Uniform Resource Identifiers (URIs) using the Domain Name System (DNS) in the domain e164.arpa </li></ul><ul><ul><li>URIs are used to identify resources on the Internet (e.g. http:// enum.nic.at ) </li></ul></ul><ul><li>The purpose of ENUM is to enable the convergence between the PSTN and the Internet </li></ul>ENUM is defined by the IETF
  10. 10. ENUM in a nutshell <ul><li>take an E.164 phone number </li></ul>+43 720 203 211 <ul><li>turn it into a FQDN </li></ul> <ul><li>returns list of URIs </li></ul>sip:richard@iphone.at <ul><li>query the DNS (for NAPTR) </li></ul>mailto:richard.stastny@oefeg.at sms tel:+436644204100 IN NAPTR 100 100 &quot;u&quot; “E2U+sip“ !^.*$!SIP:richard@iphone.at! .
  11. 11. The basic idea of ENUM (RFC3671) <ul><li>The basic idea of ENUM was </li></ul><ul><ul><li>to allow end-users </li></ul></ul><ul><ul><li>to opt-in with their EXISTING phone-numbers on the PSTN </li></ul></ul><ul><ul><li>into e164.arpa </li></ul></ul><ul><ul><li>to provide OTHER end-users with the capability </li></ul></ul><ul><ul><li>to look up contact URIs on the Internet the above end-user wants to link to this number </li></ul></ul><ul><li>This kind of ENUM is called User ENUM </li></ul><ul><li>Implemented by RIPE NCC and ITU-T </li></ul><ul><ul><li>via the Interim Procedures </li></ul></ul>
  12. 12. ENUM Implementations <ul><li>30 Greece </li></ul><ul><li>31 Netherlands </li></ul><ul><li>33 France Trial closed </li></ul><ul><li>350 Gibraltar </li></ul><ul><li>353 Ireland Trial </li></ul><ul><li>354 Iceland </li></ul><ul><li>358 Finland </li></ul><ul><li>359 Bulgaria </li></ul><ul><li>36 Hungary </li></ul><ul><li>374 Armenia </li></ul><ul><li>386 Slovenia requested </li></ul><ul><li>380 Ukraine rejected </li></ul><ul><li>39 Italy </li></ul><ul><li>40 Romania </li></ul><ul><li>41 Switzerland Trial </li></ul><ul><li>420 Czech Republic </li></ul><ul><li>421 Slovakia Trial </li></ul><ul><li>423 Liechtenstein Trial </li></ul><ul><li>43 Austria </li></ul><ul><li>44 UK Trial </li></ul><ul><li>46 Sweden Trial </li></ul><ul><li>47 Norway </li></ul><ul><li>48 Poland </li></ul><ul><li>49 Germany </li></ul><ul><li>246 Diego Garcia </li></ul><ul><li>247 Ascension </li></ul><ul><li>262 Reunion (fr) </li></ul><ul><li>290 Saint Helena </li></ul><ul><li>508 St. Pierre and Miquelon (fr) </li></ul><ul><li>52 Mexico requested </li></ul><ul><li>55 Brazil </li></ul><ul><li>590 Guadeloupe (fr) </li></ul><ul><li>594 French Guyana </li></ul><ul><li>596 Martinique </li></ul><ul><li>61 Australia Trial </li></ul><ul><li>62 Indonesia rejected </li></ul><ul><li>63 Philippines Trial </li></ul><ul><li>66 Thailand </li></ul><ul><li>65 Singapore Trial </li></ul><ul><li>7 Russia requested </li></ul><ul><li>81 Japan Trial </li></ul><ul><li>82 Korea Trial </li></ul><ul><li>84 Vietnam </li></ul><ul><li>86 China Trial </li></ul><ul><li>88234 Global Networks ? </li></ul><ul><li>87810 VISIONng UPT </li></ul><ul><li>94 Sri Lanka requested </li></ul><ul><li>971 UAE </li></ul>http:// www.ripe.net/enum/request -archives/ Delegations in e164.arpa as of Feb 7, 2007 <ul><li>1 North America (US, CA, Jamaika) </li></ul><ul><li>additional Asian countries (Taiwan…) have trials, but not in .arpa </li></ul>
  13. 13. But the problem is: <ul><li>User ENUM requires </li></ul><ul><ul><li>country opt-in </li></ul></ul><ul><ul><li>end-user opt-in </li></ul></ul><ul><li>“ Service providers” have no say in User ENUM </li></ul><ul><li>So Service Providers using IP-based technology need other solutions to be able to Interconnect </li></ul><ul><ul><li>via IP-based technology and </li></ul></ul><ul><ul><li>using E.164 Numbers </li></ul></ul>
  14. 14. Terminology <ul><li>A generic term is Administrative Domain </li></ul><ul><li>Service Providers provide services on behalf of end-users </li></ul><ul><li>„ Carrier-of-Record“ </li></ul><ul><ul><li>a service provider to which E.164 numbers are allocated for assignment to end-users </li></ul></ul><ul><ul><li>where a number is ported to </li></ul></ul><ul><li>Infrastructure ENUM is used by „Carriers-of-Record“ </li></ul><ul><li>What is the role of Enterprises? </li></ul>
  15. 15. Infrastructure ENUM is Basically Solving Two Problems <ul><li>Number Portability </li></ul><ul><ul><li>requires the hosting service provider </li></ul></ul><ul><li>IP Interconnect </li></ul><ul><ul><li>requires the ingress point to the destination network </li></ul></ul><ul><ul><li>can be derived from the hosting service provider </li></ul></ul>
  16. 16. Status Quo <ul><li>Service Providers are currently living on islands </li></ul><ul><ul><li>they interconnect via the PSTN </li></ul></ul><ul><li>To interconnect via IP </li></ul><ul><ul><li>they need also a mapping from E.164 numbers to a target name </li></ul></ul><ul><li>Infrastructure ENUM </li></ul><ul><ul><li>the only viable option </li></ul></ul><ul><ul><li>there are others (SIP Redirect, DUNDI, …) </li></ul></ul><ul><ul><li>but they do not scale well </li></ul></ul>
  17. 17. NGN/IP Interconnect (VoIP Peering) <ul><li>If we take the All-IP paradigm seriously, we have two basic requirements : </li></ul><ul><ul><li>any real-time communication originating on IP and terminating on IP MUST stay on IP end-to-end </li></ul></ul><ul><ul><li>this implies, it MUST NOT use the PSTN/ISDN to interconnect. </li></ul></ul><ul><li>Benefits are: </li></ul><ul><ul><li>improved end-to-end functionality (BB codecs, IM, video, conferencing, presence, …) </li></ul></ul><ul><ul><li>improved end-to-end QoS </li></ul></ul><ul><ul><li>no additional cost beside of IP-access </li></ul></ul><ul><ul><li>convergence possible at the end-user’s device </li></ul></ul>
  18. 18. Number Portability <ul><li>Different options implemented on PSTN </li></ul><ul><ul><li>onward routing, drop back, query on release, all call query </li></ul></ul><ul><li>Some countries use centralized databases </li></ul><ul><li>It is easy to use this data also for ENUM to provide NP also on IP </li></ul>
  19. 19. The Infrastructure ENUM options <ul><li>What are the options with Infrastructure ENUM? </li></ul><ul><li>Carrier (Operator, Private) Infrastructure ENUM </li></ul><ul><ul><li>closed </li></ul></ul><ul><li>Federation Infrastructure ENUM </li></ul><ul><ul><li>closed or open </li></ul></ul><ul><li>Global Infrastructure ENUM </li></ul><ul><ul><li>closed or open </li></ul></ul>
  20. 20. Private Infrastructure ENUMs <ul><li>Also called: </li></ul><ul><ul><li>Operator ENUM </li></ul></ul><ul><ul><li>Enterprise ENUM </li></ul></ul><ul><ul><li>Carrier ENUM </li></ul></ul><ul><li>Used by one service provider within his own network </li></ul><ul><li>May be downloaded from a centralized registry </li></ul><ul><li>Advantages: </li></ul><ul><ul><li>No user opt-in, NO REGULATORS INVOLVED , </li></ul></ul><ul><ul><li>very secure </li></ul></ul><ul><li>Disadvantages: </li></ul><ul><ul><li>Service provider responsible for all data </li></ul></ul><ul><ul><li>Savings in OPEX questionable </li></ul></ul><ul><ul><li>no global solution, </li></ul></ul>
  21. 21. Federation ENUMs <ul><li>This is currently how “service providers” interconnect: </li></ul><ul><li>Variants: </li></ul><ul><ul><li>Closed ENUM in a “walled garden” extranet (GSMA) </li></ul></ul><ul><ul><li>SIP Exchange with restricted access on the Internet (Cable providers, XConnect, SIP-IX, …) </li></ul></ul><ul><ul><li>open tree not in „e164.arpa“ (e164.info) </li></ul></ul><ul><li>Advantages: </li></ul><ul><ul><li>No user opt-in, NO REGULATORS INVOLVED , intrinsic peering agreements, savings in CAPEX, OPEX, MM-services </li></ul></ul><ul><li>Disadvantages: </li></ul><ul><ul><li>limited reach, </li></ul></ul><ul><ul><li>no global solution, </li></ul></ul><ul><ul><li>how to peer with other federations? </li></ul></ul>
  22. 22. Why Global Infrastructure ENUM? <ul><li>All types of private and federated ENUMs have serious d isadvantages: </li></ul><ul><ul><li>limited reach, </li></ul></ul><ul><ul><li>no global solution, </li></ul></ul><ul><ul><li>how to peer with other federations? </li></ul></ul><ul><li>Only numbers from providers participating in the given federation can be reached </li></ul><ul><li>To enable global reachability on IP, a single, common and global tree is required. </li></ul><ul><li>The first goal of Infrastructure ENUM is to create an anchor place where any E.164 number can be found and will: </li></ul><ul><ul><li>either be mapped directly to an ingress point of the destination network, </li></ul></ul><ul><ul><li>or at least hints can be found in which private E.164 resolution spaces the number can be resolved. </li></ul></ul>
  23. 23. Global Infrastructure ENUM <ul><li>If Infrastructure ENUM is intended to allow the mapping of any E.164 number </li></ul><ul><ul><li>that can be reached via IP </li></ul></ul><ul><ul><li>even if it terminates on the PSTN </li></ul></ul><ul><ul><li>to a SIP URI, </li></ul></ul><ul><li>Global Infrastructure ENUM must be in the public DNS </li></ul><ul><ul><li>or a new global extranet is required </li></ul></ul><ul><li>But this is useless, if the resulting SIP URI cannot be reached </li></ul><ul><li>So for Infrastructure ENUM also a global IP Interconnect (VoIP Peering) regime is required. </li></ul><ul><li>ENUM is an applet to VoIP Peering </li></ul>
  24. 24. What are the Benefits of ENUM? <ul><li>ENUM is using the DNS </li></ul><ul><ul><li>it’s there, it works, it’s global, it scales, it’s reliable, it’s open, anyone can use it… </li></ul></ul><ul><ul><li>saving CAPEX </li></ul></ul><ul><li>Enables the originating administrative domain to do an All Call Query (ACQ) to find the destination network </li></ul><ul><ul><li>Ultimate solution in Number Portability </li></ul></ul><ul><li>Provisioning is done only by the destination (recipient) administrative domain for the E.164 numbers this domain is hosting </li></ul><ul><ul><li>saving OPEX </li></ul></ul><ul><li>Enables all multimedia (MM) services for E.164 numbers for all sessions on IP end-to-end </li></ul><ul><ul><li>enables convergence (whatever that means) </li></ul></ul>
  25. 25. Current I-Ds in ENUM <ul><li>Infrastructure ENUM Requirements </li></ul><ul><li>The E.164 to Uniform Resource Identifiers (URI) Dynamic Delegation Discovery System (DDDS) Application for Infrastructure ENUM </li></ul><ul><li>Combined User and Carrier ENUM in the e164.arpa tree (interim solution) </li></ul><ul><li>The ENUM Branch Location Record (interim solution) </li></ul><ul><li>IANA Registration for an Enumservice to Hint to E.164 Resolution Namespaces (ERN) </li></ul>
  26. 26. Current Status of Infrastructure ENUM <ul><li>The Internet Drafts have been forwarded to IESG </li></ul><ul><li>The IESG does not want to define and run the Infrastructure ENUM domain </li></ul><ul><li>It is planning a liaison to ITU-T </li></ul><ul><li>ITU-T created already a correspondance group on Infrastructure ENUM issues </li></ul>
  27. 27. SPEERMINT Interconnect <ul><li>Interconnection procedures: </li></ul><ul><ul><li>(Eventually take output of ENUM) </li></ul></ul><ul><ul><li>Analysis of target URI </li></ul></ul><ul><ul><li>Check routing and peering policy (e.g. federation and NNI detection) </li></ul></ul><ul><ul><li>Discovery of next hop </li></ul></ul><ul><ul><li>Routing of SIP messages </li></ul></ul><ul><ul><li>Session establishment </li></ul></ul><ul><ul><li>Media transfer </li></ul></ul>
  28. 28. Types of Peering <ul><li>Direct peering </li></ul><ul><ul><li>the originating provider may identify and interconnect directly with the terminating provider </li></ul></ul><ul><li>Assisted peering </li></ul><ul><ul><li>involves the deployment of centralized SIP elements on the Internet or by a federation </li></ul></ul><ul><li>Indirect peering </li></ul><ul><ul><li>involves transit SIP elements for the routing of SIP messages and eventually also for media </li></ul></ul>
  29. 29. Finding the „Policies“ <ul><li>Location </li></ul><ul><ul><li>of the terminating provider </li></ul></ul><ul><li>Interoperability </li></ul><ul><ul><li>compatibility with terminating provider (identifying the NNI/UNI) </li></ul></ul><ul><li>Security </li></ul><ul><ul><li>of message transport (TLS, IPSec, VPN, ..) </li></ul></ul><ul><li>Trust </li></ul><ul><ul><li>authentication, privacy, identity, SPIT prevention, … </li></ul></ul><ul><li>Routing </li></ul><ul><ul><li>of messages to next hop </li></ul></ul><ul><li>Cost </li></ul><ul><ul><li>Fees, type of charges, … </li></ul></ul>
  30. 30. What are the benefits of SPEERMINT? <ul><li>Enable interconnection in public and „private“ environments </li></ul><ul><li>Use the DNS also for policy functions </li></ul><ul><ul><li>saving CAPEX </li></ul></ul><ul><li>Provisioning done mainly by the destination administrative domain </li></ul><ul><ul><li>saving OPEX </li></ul></ul><ul><li>Enables multimedia (MM) services for any Public User Identifier for all sessions on IP end-to-end </li></ul>
  31. 31. Benefits in a nutshell <ul><li>The major benefits of Infrastructure ENUM and SPEERMINT for (VoIP) carriers and (VoIP) service providers is to save costs: </li></ul><ul><li>Minimal CAPEX for setting up the required infrastructure to provide the routing data </li></ul><ul><li>Minimal OPEX for maintaining routing data: </li></ul><ul><ul><li>Announce the E.164 numbers you host (in ENUM) </li></ul></ul><ul><ul><li>Announce the domains you host (in DNS) </li></ul></ul><ul><ul><li>(make bilateral or multilateral peering agreements) </li></ul></ul><ul><ul><li>Query ENUM and DNS to find any other destination provider </li></ul></ul>
  32. 32. What are the Open Issues? <ul><li>The Internet is based on end-to-end communication and best effort, no central intelligence </li></ul><ul><ul><li>this causes also a lot of problems (SPAM, DoS, spoofing, phishing, …) </li></ul></ul><ul><li>The PSTN has central control, QoS and a different business model, </li></ul><ul><ul><li>but it is a one trick pony </li></ul></ul><ul><li>The dream of the NGN </li></ul><ul><ul><li>take the benefits of the PSTN (especially the business model) and move it over to IP technology </li></ul></ul>The answer is money, what was the question?
  33. 33. <ul><li>Thank you </li></ul>Richard Stastny ÖFEG +43 664 420 4100 [email_address] http://voipandenum.blogspot.com