#Glossary

Connected Services Framework (CSF) — Version 2.0

This glossary defines the abbreviations and terms used throughout the CSF documentation.

#Abbreviations

Abbreviation	Full Term	Definition
CP	Communications Provider	An organisation participating in an industry process (e.g., OTS, SforB) that creates or consumes messages and sends or receives them via a MAP. CPs include retailers, wholesalers, and agencies providing services on behalf of other CPs.
CSF	Connected Services Framework	A set of open message communication standards that define how MAPs exchange messages securely and efficiently on a peer-to-peer basis, without reliance on a centralised hub.
DDG	Detail Design Group	The original industry group that documented the requirements for the technologies and processes of switching residential customers' broadband and voice services (One Touch Switch).
DKIM	DomainKeys Identified Mail	A message authentication standard (RFC 6376) that uses PKI to verify the sender's domain identity and ensure that the message has not been altered in transit. The CSF adapts DKIM for HTTP message signing between MAPs.
DNS	Domain Name System	The internet system that resolves domain names to IP addresses. In the CSF, DNS TXT records are used to publish CP public keys and MAP associations.
GPLB	Gaining Provider Led Business Switching	The original name for the industry process for switching business telecommunications services, now branded as Switching for Business (SforB). Ofcom has not mandated a single technical solution for this process.
GPLB-SG	GPLB Steering Group	An independent body of industry stakeholders together with the OTA2, that guides and facilitates the steering meetings and publication of the SforB process documentation via FCS. The group retains the historical "GPLB" label even though the process has been renamed to Switching for Business (SforB).
HMAP	Hub Managed Access Provider	A specialised MAP type that operates as a hub-and-spoke delivery mechanism (e.g., TOTSCo). An HMAP accepts messages and forwards them among its subscribed members without engaging with the message payload.
JAM	JSON Asynchronous Message	The industry-wide messaging standard published on the OTA2 website. JAM defines the envelope format (addressing, routing, correlation) used by all CPs and MAPs regardless of the underlying transport.
MAP	Managed Access Provider	An organisation that facilitates message exchange on behalf of CPs by offering integration services, portals, and technical solutions. A CP can become a MAP of 1 (itself) by abiding by MAP rules.
MoU	Memorandum of Understanding	The agreement governing collaboration between MAPs and CPs participating in the CSF.
OTA2	Office of the Telecommunications Adjudicator	The industry body accountable for publishing and controlling RCPID Standards and the JSON Asynchronous Messaging Specification.
OTS	One Touch Switch	The Ofcom-mandated process for switching residential IAS and NBICS services between consumer CPs. All OTS messages must be routed via the TOTSCo Hub.
PKI	Public Key Infrastructure	A framework for managing cryptographic key pairs and digital certificates. In the CSF, PKI is implemented via DKIM (RFC 6376) to sign and verify messages between MAPs.
RCPID	Retail Communications Provider Identifier	A unique identifier assigned to a CP brand for the purpose of message exchange. In the CSF, RCPIDs use the UUIDv4 format (RFC 4122) and remain with the CP for life, even when changing MAPs.
RFC	Request for Comments	A publication series from organisations such as the IETF that defines internet standards, protocols, and technical specifications.
SforB	Switching for Business	The current branding for the GPLB process — the industry process for switching business telecommunications services.
TAG	Telecom Technical Architecture Group	A consortium of telecoms industry stakeholders responsible for the development, publication, and change control of the CSF. The TAG meets weekly via its steering group.
TLS	Transport Layer Security	A cryptographic protocol providing secure communication over networks. The CSF mandates TLS 1.3 (RFC 8446) for all connections.
TOTSCo	Telecoms One Touch Switching Company	The organisation operating the centralised hub for OTS message routing. TOTSCo also publishes OTS process and technical documentation. For SforB, TOTSCo may operate as an HMAP within the CSF.

#Key Definitions

#CP Registry

A JSON data structure published by each MAP containing detailed information about that MAP, its connected CPs, and their supported processes (including RCPIDs, brand names, PKI signing domains, resource URLs, and contact details). Both the MAP and each individual CP can include a contact array using the same structure — the MAP contact is for MAP-to-MAP technical issues, while each CP's contact is for CP-to-CP operational escalations (sales, support, technical). Each MAP publishes its own CP Registry and makes it available to other MAPs via an OAuth 2.0-protected API endpoint. The CP Registry is the outward-facing data that MAPs share with each other.

#Master Registry

The private, consolidated view built by each MAP when it collects and converges all other MAPs' CP Registries. The Master Registry contains the full routing, PKI signing, and contact details for every CP across the entire CSF network. It is held privately by the MAP and used internally for message routing, DKIM signature verification, and CP-to-MAP resolution. Each MAP maintains its own copy of the Master Registry.

#Directory

A filtered, cut-down version of the Master Registry that a MAP shares with its own CPs. The Directory lists the brand names and RCPIDs available to switch with — the information CPs need to populate drop-down lists, search-as-you-type fields, and message addressing. It excludes inter-MAP routing details, PKI signing domains, and other sensitive operational information. When a CP selects a destination from the Directory, the MAP uses the RCPID to look up the full routing and signing details in its private Master Registry.

An onboarded MAP that is assigned (via round-robin rotation) to guide a new MAP through the onboarding process. The Sponsor MAP validates the new MAP's technical readiness, conducts testing, and acts as a gatekeeper to the CSF network.

#New MAP

An organisation that wishes to join the CSF and begin exchanging messages with other MAPs. A New MAP must complete the sponsored onboarding process before it can publish its registry or exchange production messages.

#Bit pipe

Refers to a network provider that simply moves data without adding value or examining content. The CSF is, by design, a bit pipe for SforB and any other industry processes that use it — it carries the JAM envelope and does not interpret the message body. The full normative definition is in Definitions §2.3.

#SOR (Switch Order Reference)

A reference number associated with a Switch Order. SORs have a validity period (typically 31 days) and cannot be transferred between MAPs; they must be re-issued. The full definition is in Definitions §2.6.

#Letterbox

The REST API endpoint used by MAPs to send and receive messages. The letterbox accepts JAM-formatted JSON messages over HTTPS (TLS 1.3) with OAuth 2.0 authentication and returns an HTTP 202 to acknowledge receipt.

#Routing Group

A named collection of routing ID patterns (expressed as regular expressions) that determines which message types are accepted by a specific MAP service endpoint. For example, businessSwitch.* for SforB messages or residentialSwitch.* for OTS messages.

#Feature Release

A mechanism within the CSF that allows MAPs to adopt new capabilities incrementally without requiring all MAPs to upgrade simultaneously. MAPs advertise their supported feature sets in the registry, enabling automatic negotiation of the highest compatible version between interacting parties.