All-IP Transition Presents Telephone Number Length Challenges
As Deutsche Telekom transitions from ISDN to IP telephony, businesses face potential telephone number length limitations. The portability of these numbers can emerge as a significant challenge requiring careful planning.
Companies preparing for Deutsche Telekom's transition from ISDN systems to IP telephony may encounter unforeseen difficulties related to their telephone number lengths. Although the transition is scheduled to begin in 2018, many businesses remain unaware of the limitations associated with number portability.
A key issue lies with the International Telecommunication Union's (ITU) E.164 recommendation, which sets a maximum length of 15 digits for national telephone numbers, including country codes. Previously, the ISDN system offered more flexibility, and some companies may have extended their numbers beyond this limit to accommodate features such as screen facsimile.
When numbers are ported to an IP system, providers adhere more strictly to the E.164 standard. If a company's assigned number exceeds the allowed 15 digits, the provider may refuse to port it. While Germany's Federal Network Agency (Bundesnetzagentur) permits lengths up to 15 digits, this does not establish a legal right to exceed this boundary for portability.
Axians Germany strongly advises businesses to review their telephone number lengths well in advance of the transition period. Analyzing the number structure and communicating with the service provider is crucial to ensure a smooth migration and avoid number loss or alteration. Although most numbers likely will not require changes, a thorough examination is essential.