The objective of the e-SENS building block “e-Delivery” is to establish a common transport infrastructure suited to the requirements of cross-border communication between eGovernment applications in different domains. This common transport infrastructure leverages the work of the previous Large Scale Pilots (LSPs) and combines their results in line with a modular approach. The goal is for the infrastructures in use by the other LSPs to converge over time towards this common standard.

The e-SENS e-Delivery infrastructure supports interoperable, secure and reliable exchange of structured, non-structured and/or binary data within (at least) asynchronous communication scenarios. As in most preceding LSPs, in e-SENS the common e-Delivery infrastructure does not replace existing infrastructures, but instead aims to transparently interconnect existing electronic delivery communities:

  • Communities set up by the Member States for general eGovernment purposes
  • Sector-oriented communities such as e-Procurement, e-Health and e-Justice


In e-SENS, e-Delivery is based on the concept of a four-corner model, where end entities (corners one and four) exchange messages via gateway intermediaries (corners two and three). The infrastructure only standardises communication between these intermediaries. Communication between gateways and end entities may use e-SENS e-Delivery, but may also use a different solution. This model is illustrated in the following diagram:




e-Delivery builds on earlier initiatives to converge the transport infrastructures of the PEPPOL, SPOCS and e-CODEX LSPs, for which an e-Delivery convergence task force was set up. This group identified version 3 of OASIS ebXML Messaging Services (ebMS3), service discovery protocols and formats developed in PEPPOL (submitted to the OASIS BDX Technical Committee) and evidence messages standardised in ETSI ESI as building blocks for converged e-Delivery. The e-CODEX project has developed an e-Delivery solution based on these building blocks, which is currently in use in a number of Member States. This solution, together with the experience gained in the e-CODEX project, is an important input for e-SENS.    

e-Delivery Architecture

e-SENS has identified, and recommends for use in the e-SENS pilots, a “Core e-Delivery” high-level building block, which will be delivered as:

  • a set of architecture building blocks – defined technical specifications
  • a solution building block that implements the specifications in a software product


The Core e-Delivery architecture building blocks are the following:

  • Message Exchange Protocol – this provides secure and reliable exchange of single payloads or groups of payloads in any structured or unstructured format. The recommended transport protocol is ebMS3, profiled for use in four-corner topologies. For interoperability reasons, the e-SENS profile will align closely with the AS4 profile of ebMS3, which is implemented by a growing number of commercial and open source solutions and is also adopted by other large user communities.
  • Addressing of Entities – this provides a standard notation for party identifiers and party identifier types that allows existing identification schemes to be reused. The recommended end entity addressing format for legal entities is the ebCore Party ID type, which leverages existing party identification schemes. The project will define a similar scheme for natural entities to support interactions with citizens.
  • Service Location – this defines a standard location for metadata service providers.  It provides address and access information related to capability services.
  • Capability Lookup – this is a technical service to accommodate a dynamic and flexible interoperability community. A capability lookup can provide metadata about the communication partner’s interoperability capabilities at all levels defined in the European Interoperability Framework (the Legal, Organisational, Process, Semantic and Technical interoperability levels). 


Furthermore, the Backend Integration ABB facilitates the connection between the national infrastructure and the e-SENS infrastructure.

In parallel to the architecture building blocks, e-SENS collaborates with the Directorate-General for Informatics (DIGIT) and e-CODEX to deliver a solution building block, an implementation that:

  • Implements Core e-Delivery
  • Is free and open source
  • Is mature and suited for production use
  • Is fully tested and supported. 


However, organisations may also implement e-Delivery using other solutions, such as commercial messaging products.

The e-Delivery building block of CEF (the Connecting Europe Facility) is to a large extent be based on e-SENS e-Delivery and the e-SENS trust models.