VoIP and IP-IC Regulatory aspects Giovanni Santella g.santella@agcom.it
What is VoIP?
VoIP call scenarios (1) PC-to-PC PC-to-Phone
VoIP call scenarios (2) Phone-to-Phone
The value chain for the provision of VoIP
User addressing by URIs providera.net DNS providerb.net SIP server sip:bob@providerb.net DNS SRV lookup providerb.net SIP server sip:bob@providerb.net session sip:alice@providera.net sip:eve@providera.net sip:eve@providerb.net sip:bob@providerb.net
User addressing by E.164 ENUM DNS ENUM IN NAPTR 0.1.4.0.2.4.0.8.7.3.4.e164.arpa.?... NAPTR... "!^.*$!sip:bob@providerb.net!" providera.net DNS providerb.net tel:+43780420410 SIP server DNS SRV lookup providerb.net SIP server sip:bob@providerb.net session sip:alice@providera.net sip:eve@providera.net sip:eve@providerb.net sip:bob@providerb.net
The market Several VoIP public available offers exist on the market. Some of these offers are positioned as a substitute for traditional publicly available telephony services offered over circuit-switched networks. Other offers show different characteristics and include additional features, such as the possibility of nomadic use of the terminals. In addition the former offers are characterized by nonhomogeneous levels of quality and customer protection.
Tariff schemes: Retail The most common arrangements worldwide are referred to as Calling Party Pays, or CPP. The party that places the call pays a price. The recipient pays nothing. Increasingly popular in recent years are tariff schemes based on a fixed fee (or flat rate) per unit time (usually per month), independent of usage.
Interconnection tariff schemes Wholesale arrangements in the PSTN/PLMN generally are of one or two forms: either they follow the principle of Calling Party s Network Pays or else they are voluntarily negotiated between the networks. If negotiated, the networks often, but not always, agree not to charge one another (a arrangement known as Bill and Keep).
Calling Party s Network Pays (CPNP) Calling Party s Network Pays (CPNP) arrangements reflect a payment at the wholesale level from the originating network (the network whose customer placed the call) to the terminating network (the network whose customer received the call).
IP interconnection models The majority of connections between two IP-based networks today take place according to one of two basic interconnection models: transit and peering.
Peering vs transit Peering is an agreement between ISPs to carry traffic for each other and for their respective customers. Peering does not include the obligation to carry traffic to third parties. Peering is usually a bilateral business and technical arrangement. Transit is an agreement where an ISP agrees to carry traffic on behalf of another ISP or end user. One provider (the transit provider) agrees to carry traffic to third parties on behalf of another provider or an end user (the customer). In most cases, the transit provider carries traffic to and from its other customers, and to and from every destination on the Internet, as part of the transit arrangement.
VoIP Regulatory issues
EU Framework Definitions ECS PATS Electronic Communication Service (ECS) Service (normally) provided for remuneration Consists wholly or mainly in the conveyance of signals on Electronic Communication Networks Public Available Telephone Service (PATS) = Public Available Service = Originating & Receiving (inter)national calls = Access to Emergency Service (112) = E.164 numbering scheme
EU Regulatory framework The EU Regulatory framework defines an Electronic Communication Service (ECS) as a service normally provided for remuneration which consists wholly or mainly in the conveyance of signals on Electronic Communication Networks; a Public Available Telephone Service (PATS) is a service available to the public for originating and receiving national and international calls and access to emergency services through a number or numbers in a national or international telephone numbering plan.
Obligations : PATS vs. ECS Directory Publication of price & tariffs Integrity & Availability Number Portability Emergency Services Security & Privacy Conditions ~ use of numbers Directory entry information & access Quality of Service - publishing Contracts to Consumers Universal Service Financing Notification of NRA ECS Security & Privacy Conditions ~ use of numbers Directory entry information & access Quality of Service - publishing Contracts to Consumers Universal Service Financing Notification of NRA PATS
The evolution of the VoIP Regulatory approaches At the beginning of VoIP
Categories of VoIP services from a regulatory point of view IP telephone server PSTN / Mobile network G AT E W AY IP xdsl xdsl Peer-to-peer (e.g. Skype Classic): based on free downloaded software, free of charge calls, voice and signaling circulate through servers or PC not managed by skype itself, users register into a Skype DB. (Regulation: Information Society Service, No regulated as an ECS) IP-phone-PSTN Phone (e.g. Skype Out or Skype IN). Necessary interconnection through a GW, call charge may be indep. of distance. Skype Out: possible to call E.164 numbers of PSTN or mobile network, but no to receive from PSTN/mobile since users do not have been assigned an E.164 number (regulated as ECS). Skype IN: Skye out + possible to receive from PSTN/mobile (regulated as ECS or PATS). IP provided by an integrated operator: based on an all IP managed network. QoS guaranteed. (Regulated as ECS or PATS).
Italian VoIP regulation (1): issues Authorization regime; Numbering for VoIP services, rights of use and number portability Access to emergency services and caller location; Network integrity, quality and availability of service.
Italian VoIP regulation (2): authorization regime Decision 11/06/CIR The following two VoIP service categories are identified 1) publicly accessible telephony services (PATS) with functional features (quality, availability, access to emergency services, etc.) similar to traditional voice services offered over (PSTN), use of the National Numbering Plan and the possibility to call the emergency services. The network terminal point is identified by a geographic number (decade 0); the use can be nomadic only within the district identified by the assigned number. 1) ECS nomadic voice services: allowed nomadic use of the user terminal. For this category of services the AGCOM has introduced a new numbering range (decade 5) in the National Numbering Plan (NNP). Also services like skype-out (allow call to PSTN without E.164 number assignment) fall in this category. It is not clear from the ECS definition whether peer to peer VoIP services fall in this category.
Italian VoIP regulation (3): use of geographic numbers 1) Geographic numbers are used for fixed PATS (publicly available telephony services) voice services using both traditional circuit switched networks and VoIP. QoS comparable to PSTN voice services. Internet IP-Adr. x2 NTP on telephony level:06 xy z Packet network IP-Adr. x1 Gateway NTP on PATS level : 06 xy z PSTN NTP (fixed location) nomadic use forbidden
Italian VoIP regulation (4): nomadic VoIP services 2) A new number range (55 UU U) services is introduced for innovative services (i.e. nomadic services). Addressing of subscribers in connection with public telephone services, which enable the subscriber to hold its number independently of the location ( nomadic services). Similar as in case of mobile (radio) services subscriber access on telephony level (NTP) follows subscriber to actual usage location. Internet IP-Adr. x2 NTP on telephony level:56 xy z Packet network IP-Adr. x1 Gateway NTP on PATS level : 56 xy z PSTN NTP (fixed location) nomadic use allowed
Italian VoIP regulation (5): access to emergency services, NP 3) Access to Emergency services, CLI transmission, and number portability is provided by operators that use both geographic and non geographic number ranges and are interconnected to PSTN. Calling no: 55 xy z Emergency Service Center Internet Packet network PSTN Gateway NTP on telephony level: 55 xy z Calling no.: 55 xy z 55 xy z nomadic 55 xy z
Italian VoIP regulation (5.1): access to emergency services, NP All VoIP providers that are interconnected to the PSTN (this excludes peer to peer) have to provide access to emergency services. In the case of nomadic services, user localization is provided to the extent technically feasible. In the case of nomadic use the end-user has be informed by the VoIP provider about any restrictions in routing emergency calls and providing caller location information.
Italian VoIP regulation (6) 1. Access to Emergency services and number portability is provided by operators that use both geographic and non geographic number ranges. 2. In the case of nomadic use, user caller location information is provided to the extent technically feasible when calling the emergency number. 3. In the case of nomadic use of VoIP services the end-user should be informed about difficult localization and routing to the nearest emergency centre. 4. Further requirements related to localization and number portability implementation will be reviewed and updated after standards have matured.
Italian VoIP regulation (7) Single data base creation All undertakings which assign telephone numbers (including VoIP providers) include their subscribers in the directory enquiry services and directories and contribute to the creation of a single data base of numbers.
Interoperability and Interconnection Issues in VoIP
Key concepts for public VoIP (1) Voice over IP needs to inter-operate with PSTN (Registration, address translation,..)
Key concepts for public VoIP (2) Signalling protocols need to Inter-work H.323 and SIP zones need to be made to inter-work to support consistent services Problem: Inter-working between proprietary SIP implementation.
Interconnection models Direct interconnection between two infrustructured operators Model replacing current regulated CSS7 IC Operators may agree on more IC points, each one realized by a dedicated SBC (Session Border Controller)
Neutral Access Point (NAP) model More SBC belonging to infrustructured operators are co-located at an agreed neutral site and interconnected through VLANs VoIP interconnection is carried out through a logical configuration of SBCs
Modello di interconnessione tra operatori di servizi di comunicazione vocale nomadici interconnessione che si avvale solo di infrastrutture di trasporto pubbliche
Requirements at the IC point Logical and physical separation between operators VoIP domains Possible signaling protocol translation and voice transcoding Security Recording of traffic volume and data for billing Supported standards: SIP, SIP-T, H.323
Protocol requirements that each Operator has to be compliant with at the IC-IP point to be interoperable Signalling: at least on between Some examples of agreements DTMF management: at least one between Codecs: G.711, PCM at 80kbps, MOS 4.0 plus at least one between
L evoluzione della rete di Telecom
Number of Points of Interconnection (PoI) A particularly difficult NGN migration challenge flows from the positive opportunity to simplify and collapse the network into a smaller number of geographic locations. Recent decision 55/11/CIR starts a public consultation on IP interconnection technical specification and regulatory issues: about 30 PdIC, decreasing from the current 630 SGU.