Regulatory information

Separated accounts

These documents describe Proximus’ separated accounts. This publication is made after the adoption of a binding decision of the BIPT and is made without prejudice and any adverse recognition.

Network specifications

The documents in this section describe the technical interface characteristics of the Proximus network, according to the products and services involved. These specialized documents are mainly directed towards the manufacturers of terminal equipment, so as to guarantee its compatibility with our network.

These specifications describe the situation of the Proximus network and services. They will be subject to modifications for corrections or when the network or the services will be modified. Please take into account that modifications can appear at any moment. Therefore, the reader is requested to check regularly with the most recent list of available specifications that the document in one's possession is the latest version.

Proximus cannot be held responsible for any damages due to the use of a version of this specification which is not included in the most recent list of available specifications (list always available with a request to the e-mail address mentioned in the last paragraph).

Although every care has been taken in the preparation and publication of these documents, errors in content, typographical or other, may occur. If you have any remarks regarding their accuracy, please send a mail to and your remark will be transmitted to the right Proximus department.

For any questions about the content of these specifications, don't hesitate to send a mail to We commit ourselves to give you an answer as soon as possible.

Title Last version Last version date
PXM IMS Corporate VoIP - UNI specification - SIP signalling - Enterprise_Voice_Multi 2.2 September 2019
PXM IMS Corporate VoIP - UNI specification - SIP signalling - Business Trunking with IMS services 2.4 September 2019
PXM IMS Corporate VoIP - UNI specification - SIP signalling - Wireless Office extended 2.2 September 2019
PXM IMS Corporate VoIP - UNI specification - FAX over IP 2.0 June 2019
PXM IMS Corporate VoIP - UNI specification - General 2.3 September 2019
PXM IMS Corporate VoIP - UNI specification - Address templates 2.3 September 2019
Transmission and interface characteristics of VDSL service 3.0 03-Jun-14
Short message communication for PSTN/ISDN 1.4 19-Nov-07
ADSL2 annex L 1.0 20-Apr-07
ADSL2+ over ISDN 1.0 20-Jun-05
ADSL2+ over POTS 1.0 20-Jun-05
SMS interoperability 2.1 15-Oct-04
Information Tones 1.3 10-Apr-03
ISDN - DSS1 - NETWORK LAYER 3 - Handling of the number information 1.1 10-Apr-03
16 kHz Charge Event Notification 1.3 10-Feb-03
Completion of Calls to Busy Subscriber (CCBS - Ring Back) 1.3 10-Feb-03
Analog Subscriber Line Signalling (Basic Call) 4.1 24-Jan-03
Euro-ISDN (Basic Call) 2.3 24-Jan-03
Advice of Charge (AOC) 1.3 24-Jan-03
PSTN: Subscriber line protocol for display (and related) services 3.3 10-Jan-03
ISDN - DSS1- NETWORK LAYER 3 - Calling Name Identification Presentation (CNIP) 1.1 10-Jan-03
Subscriber Control Interface (SCI) 2.1 24-Dec-02
STM-4 and VC-4-4c digital leased lines 1.0 10-Dec-02
ISDN - DSS1 - NETWORK LAYER 3 - Subscriber control procedures (Stimulus protocol) for ISDN supplementary services 1.0 31-Oct-02
The Public OFFNET Service 1.0 23-Sep-02
SDH leased Lines 1.2 10-Jul-02
Multi-Fractional STM-1 digital leased lines 1.0 10-Jul-02
Ethernet link 2.0 25-Jun-02
Colo to Colo or Colo to PoP Backhaul leased lines - Provision of 2048 kbit/s digital links 1.0 12-Jun-02
Colo to Colo or Colo to PoP Backhaul leased lines - Provision of 34 Mbit/s digital links 1.0 12-Jun-02
Colo to Colo or Colo to PoP Backhaul leased lines - Provision of SDH VC-4 digital links 1.0 12-Jun-02
The Private ONNET Service 1.0 25-Feb-02
SHDSL (Single-pair High-speed Digital Subscriber Line) 1.0 23-Jan-02
34.368 kbit/s digital leased lines 1.2 28-Dec-01
140 Mbit/s leased lines 1.2 28-Dec-01
Transmission and interface characteristics of the galvanic leased lines service 2.1 13-Aug-01
Transmission and interface characteristics of PSTN service 2.1 26-Feb-01
ONP 64 kbit/s digital leased lines 1.2 26-Jul-00
Nx64 kbit/s digital leased lines 1.2 26-Jul-00
Multidestination leased lines (MD) or Multifractional E1 (MFE1) 1.2 26-Jul-00
ADSL over POTS 1.0 28-Feb-00
ADSL over ISDN 1.0 28-Feb-00
Transparent 2048 kbit/s digital leased lines 2.0 10-May-99
Structured 2048 kbit/s digital leased lines 2.0 10-May-99
ONP (D2048s) 2 Mbit/s digital leased lines 1.0 18-Feb-99
Analogue leased lines of special quality 1.1 08-Feb-99
Analogue leased lines M1025 1.1 08-Feb-99
Analogue leased lines of ordinary quality 1.1 08-Feb-99
Internet Protocol (IP) Connectivity 1.1 08-Feb-99
Transmission and interface characteristics of ISDN services 1.0 22-Jul-98

Future updates

Considering the implementation of the R&TTE directive (directive n° 1999/5/EC of the European Parliament and the Council of 09/03/1999), Proximus publishes the updates of its UNI (User to Network Interface) specifications 6 months before their official validation.

Nevertheless for minor updates or redesign, after BIPT (Belgian Institute of Postal services and Telecommunications) consent, this publication delay could be less than 6 months.

Cyber Security Incident Response Team - “CSIRT”

Proximus Cyber Security Incident Response Team
RFC 2350 Description

Date 22/06/2015
Sensitivity Unrestricted
Our reference PXS-CSIRT-RFC2350-v1.2


1. Document Information

This document provides formal description of the PXS-CSIRT based on RFC 2350.

1.1 Date of Last Update

This is version 1.3, published on August 7, 2016.

1.2 Distribution List for Notifications

Notifications can be sent to

1.3 Locations where this Document may be found

1.4 Authenticating this Document

Document should carry a valid PGP signature of the CSIRT Manager in order to assure its authenticity.

2. Contact Information

2.1 Name of the Team

PXS-CSIRT – Proximus Cyber Security Incident Response Team

2.2 Address

K. Albert-II Laan 27
B-1030 Brussels

2.3 Timezone


2.4 Telephone Number

+32 2 202 6046

2.5 Facsimile Number

Not available.

2.6 Other telecommunications

Not available.

2.7 Electronic Mail Address

2.8 Public Keys and Encryption Information

E-mail address:
Key ID : 5D0B022A7CFBC5B3
Length : 2.048
Fingerprint: 8671 CBF3 C010 E4F0 676A 9CD7 5D0B 022A 7CFB C5B3

2.9 Team members


2.10 Other Information


2.11 Points of Customer Contact

The preferred method for contacting PXS-CSIRT is via e-mail If it is not possible (or not advisable for security reasons) the PXS-CSIRT can be reached by phone (see Telephone Number) during extended business hours from 07.00 until 18.00.


3. Charter


3.1 Mission Statement

The Proximus CSIRT (PXS-CSIRT) is the central incident response team of the Proximus Group and its mission is to provide information and assistance to reduce the risks of cyber security incidents as well as responding effectively to such incidents when they occur. The team strives to be an international example for Cyber Security Intelligence and Expertise throughout all areas of Incident Response. The Proximus CSIRT gathers, filters, analyses and disseminates threat intelligence in order to proactively communicate about upcoming attacks against the Proximus Group.

3.2 Constituency

The constituency of the PXS-CSIRT is two-fold:

The PXS-CSIRT is not intervening for cyber security incidents that are not occurring on Proximus managed infrastructure. That means that consumer equipment (eg laptop) does not fall in the scope of the PXS-CSIRT’s responsibilities.  Affiliates (Telindus NL, Telindus UK, Telindus LU, Tango LU, BICS) are part of the commercial-organization constituency.
In general, the full AS5432 is owned by Proximus. However, these also include IP addresses that are statically or dynamically assigned to customers for which Proximus will not be intervene outside of the legal framework that we are bound to operate in.

3.3 Sponsorship and/or Affiliation

The Proximus Group Information Security Steering Committee (GISSC) led by the Proximus CISO and consisting of Directors of all internal divisions has mandated a full authority to the PXS-CSIRT to immediately mitigate the impact of any cyber security incident.

3.4 Authority

As per the mandate of the GISSC, in order to immediately mitigate the impact of a cyber security incident, the Proximus CSIRT has full authority to implement corrective controls, within the legal and regulatory framework it is bound to work in.

4. Policies

4.1 Types of Incident and Level of Support

The PXS-CSIRT is classifying all incidents, based on the following categories:

Unauthorized Access

Denial of service

Vulnerability exploitation

Data Disclosure

Malicious code

Brand protection


Social engineering

Policy violation

Any incident reports that do not fall under any of these 9 categories, will be handled and prioritized, based on their impact.
Target service level for responding to any incidents reported to the PXS-CSIRT is 90% within 1 business day.

4.2 Co-operation, Interaction and Disclosure of Information

The Proximus CSIRT is actively participating within the ETIS EU CERT group, which consists of Telco CERT group throughout Europe.  This information-sharing working group is mainly focusing on incidents that have been reported and analysed by the different CERT teams. In addition to ETIS, the Proximus CSIRT is also an active member of the FIRST and Trusted Introducer communities.
Nationally, Proximus is one of the founding members of the Cyber Security Coalition where the Proximus CSIRT leads the Inter-CSIRT working group. There is also active collaboration with the national CERT in Belgium (CERT.BE), as well as different Law Enforcement Agencies, (military) intelligence services, regulatory bodies, etc.
Next to the corporate security policy on data classification (used internally) the PXS-CSIRT applies the Traffic Light Protocol for information that is shared and/or distributed with trusted parties.
All incident-related communication with other CERTs will be tagged with a unique identifier, referring to the incident number, as recorded in the PXS-CSIRT incident management system.
Communication with constituencies will be primarily via e-mail, in close collaboration with Internal Communication and/or Proximus Press team.


4.2.1 RED - personal for named recipients only


In the context of a meeting, for example, red information is limited to those present at the meeting. In most circumstances, red information will be passed verbally or in person.

4.2.2 AMBER - limited distribution

The recipient may share AMBER information with others within their organization, but only on a ‘need-to-know’ basis. The originator may be expected to specify the intended limits of that sharing.
Information in this category can be circulated widely within a particular community. However, the information may not be published or posted publicly on the Internet, nor released outside of the community.

4.2.3 GREEN – peers and partners, non-public

GREEN may be shared with peers and partner organizations within their sector or community, but not via publicly accessible channels.

4.2.4 WHITE - unlimited

WHITE may be distributed without restriction, subject to copyright controls.

4.3 Communication and Authentication

All communication that is above “green” must be transmitted through secure channel only.


5. Services

Reactive Services

Proactive Services

Quality Management Services

Alerts & warnings


Awareness building

Incident handling

Development of security tools

Education & training

Incident analysis

Intrusion detection services

Threat analysis

Incident response

Technology watch

Security consulting

Incident response support

Trend and neighbourhood watch


Incident response on-site

Security-related information dissemination


Incident response coordination


Responsible disclosure


Vulnerability response


Artefact coordination

Artefact analysis


Artefact response


Forensic analysis


6. Incident Reporting Forms

E-mail only


Responsible Disclosure

Have you discovered a security problem? Let us know!

Why Proximus believes in Responsible Disclosure

Proximus is continuously working on improving the performance and security of its networks and IT systems. The privacy of our customers’ data is hereby respected at all times. Despite all the measures, a security vulnerability may occur in one of our systems or networks. Have you discovered such a  security issue or found evidence of it, let us know. We would like to collaborate with you to solve this problem as quickly as possible.

Some agreements

To prevent any kind of abuse by others of the potential vulnerability, we ask you to always respect the following guidelines of our Responsible Disclosure policy when sending a notification :

What can you test?

Suspected security vulnerabilities that can be misused for illegal purposes and which occur:

What can you expect from Proximus?

Proximus appreciates your help in optimizing the security of its systems and networks. That's why we will do our utmost to have all contacts in a fair and respectful way:

If you report us a security problem, we will get in touch with you within 2 working days. It goes without saying that we can reach you via the e-mail address or other contact information you left behind. We also keep you informed of further developments.

In case of abuse