PSTN switch of and migration to VoIP - the impact on “over the top services” 7 February 2019 PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM
What is happening and why? Initial focus on ‘emulating’ PSTN PSTN approaching end of life • • Many systems are obsolescent Continue use of analogue transmission and support costs increasing over copper • • Providers have signalled intention This approach already being adopted to retire PSTN by 2025 by some incumbents in Europe • However, it is an interim step to full ‘voice over broadband’ Voluntary migration now, but Providers moving to voice over IP forced migration will follow (VoIP) • • Start date and length of voluntary Use a broadband connection to make migration period will vary by Provider calls over copper and fibre connections • Date by which Providers will switch off • PSTN will vary too. No UK-wide date IP services already available and commonly used by businesses • Migration expected to be completed by • 2025 Will become more common in the mass market PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM
PSTN Migration – Technical detail • 5500 telephone exchanges • Specialised equipment Exchange Home Current – Bespoke standards and protocols PSTN – C7 (SS7 in US) out-of-band signalling Broadband – Enables call set-up, number portability, routing and tear down Voice service • Equipment is reaching its end of life – Parts and skills to repair them are becoming scarce Future • Three companies in the UK face the challenge – BT, KCOM and Virgin Media – Telent maintains the PSTN equipment on behalf of operators in the UK • Each are approaching the challenge in slightly different ways over different timescales – Voice over Broadband (BT), Voice over DOCSIS (VM), Emulation (KCOM) PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 3
Migration is led by Providers • Responsibility for ensuring that the migration is efficient and straightforward lies with providers because they are: – Taking the commercial decision to switch off the PSTN – Setting the timescales (different timings, depending on the company) – Communicating with users and over-the-top service providers – Obliged to protect vulnerable consumers – Offering test facilities for over-the-top service equipment that are representative of the eventual solution. However, migration to IP raises issues for government, industry and the regulator. So there is a need to work together to achieve a successful outcome. PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 4
Part of an international trend • Many other telecommunications providers are already migrating to all-IP networks. • Deutsche Telekom has completed the migration of its customers to VoIP in Macedonia, Slovakia and Croatia and is due to complete migration in Germany by the end of 2019. PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 5
Consumer Impact – Technical Detail • Many consumers have already migrated without major issues – For example, those with Sky and TalkTalk • Customers will be offered new services and possibly new phone handsets – Handsets will connect with broadband router rather than the ‘master socket’ • Better and more flexible services achieved through: – Session Initiation Protocol (SIP) that allows different voice capabilities including video and real-time text – Improved bandwidth control to individual calls to offer enhanced voice quality, through improved codecs • Some consumers may face challenges: – Those that are unable to connect phone to router (e.g. visually impaired) • Also, conventional telephone lines supply electricity to the phone to allow a corded phone to work in the event of a power cut – A voice service that relies on the broadband service will need domestic mains power to work, which will not work during a power cut – So without an alternative means of power all calls, including those to the emergency services, will not be possible • The identification of those that are at risk, providing clear communications and providing suitable solutions is vital PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 6
Other Services – Technical Detail • The scale, stability and reliability PSTN has encouraged myriad services and applications to flourish on the network – But the PSTN has been designed and built to support voice, not these services – And the PSTN itself consists of many interconnected networks • Some services use Dual-Tone Multi-Frequency (DTMF) signalling – Others, such as modems, use voiceband frequency shift keying (e.g. V.21), • IP-based networks are designed to comply with, or align with, national (NICC) and international (IETF) standards to allow voice – IP characteristics, such as packet loss or jitter, are not expected by these services, causing them to respond in unexpected ways – Consequently the performance of OTT services may severely degrade, or stop working altogether • This issue was first identified in BT’s 21CN migration in early 2000s – But the full extent of the problems and adoption of viable solutions was not resolved • Testing has begun at BT labs, and is due to start with Virgin Media – But the tests will never be comprehensive or totally conclusive, given the full range of systems and characteristics • Messaging to consumers and stakeholders as to options and recommendations will be crucial PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 7
Potentially affected services Telecare alarms Telemetry Retail payment terminals Fire alarms Traffic lights , lighthouses … Security alarms • Contact your telecoms provider to find out about timetable and potential impact • Utilise providers’ testing facilities where available PROMOTING CHOICE • SECURING STANDARDS • PREVENTING HARM 8
Recommend
More recommend
