Session Initiation Protocols


Protocols in this table describe extensions made to the Session Initiation Protocol (SIP) that enhance the functionality provided by Communications Server. Communications Server is based on SIP. It acts like a SIP registrar and proxy, as described by [RFC3261]. SIP is used by terminals to establish, modify, and terminate multimedia sessions or calls.

Protocol name


Short name

Connection Management Protocol

Describes the functional behavior for a protocol client to automatically discover the address of the protocol server, and for maintaining a persistent, reliable, in-order transport between them.


Routing to Exchange Unified Messaging Extensions

Includes Session Initiation Protocol (SIP) extensions that are used by Communications Server to route calls to Exchange Unified Messaging and to generate user notification e-mails on call events.


Call Control for Exchange Unified Messaging Protocol Extensions

Describes the SIP extensions that are used to integrate Office Communicator and Exchange Unified Messaging to play voice messages and use voice commands to manage Exchange Unified Messaging mailboxes.


Session Initiation Protocol (SIP) for PSTN Calls Extensions

Describes the SIP extensions for the interface between Office Communicator and Communications Server to communicate with public switched telephone network (PSTN) and private branch exchange (PBX).


Client Error Reporting Protocol

Describes the protocol for Communications Server to report diagnostic and troubleshooting information to the SIP-based protocol client and for the SIP-based protocol client to report an error to Communications Server.


Presence Protocol

Describes the extensions of SIP that make up the Presence Protocol used by Office Communicator and Communications Server to allow publishers and subscribers to exchange presence-related data over SIP.


Quality of Experience Monitoring Server Protocol

Describes the protocol used for publishing audio and video Quality of Experience (QoE) metrics.


Session Initiation Protocol (SIP) Compression Protocol

Describes a SIP extension to compress data between the protocol client and the protocol server. The protocol has two phases. The negotiation phase advertises and exchanges compression capabilities. The SIP Compression Protocol uses a modified form of the Microsoft Point-to-Point Compression (MPPC) Protocol, as described in [RFC2118], to compress SIP data.


Session Initiation Protocol (SIP) Authentication Extensions

Describes SIP extensions used for authentication functionality.

This protocol defines NT LAN Manager (NTLM) Authentication Protocol, Kerberos, and Transport Layer Security with Derived Session Key (TLS-DSK) authentication schemes based on the general authentication framework described in [RFC3261]. This protocol also describes the details and extensions for the Asserted Identity mechanism, which is based on [RFC3325], and the Referred-By mechanism, which is based on [RFC3892].


Session Initiation Protocol (SIP) Routing Extensions

Describes SIP extensions for call routing used by SIP-based protocol clients, proxies, and protocol servers. SIP Routing Extensions also include extensions to SIMPLE-based presence, as described in [RFC3261] and [RFC3265].


Session Initiation Protocol (SIP) Registration Extensions

Describes SIP extensions to enable Communications Server to provision the protocol clients as part of the registration process.


Response Group Service Web Service Protocol

Describes the procedure to enable a protocol client to access agent information exposed by a protocol server.


PSOM Shared Object Messaging Protocol

Describes the PSOM Shared Object Messaging (PSOM) protocol that is used to exchange messages between the protocol client and protocol server. A message typically represents a method invocation of a remote object, with a sequence of understood parameters.

This protocol is designed to facilitate communications for data collaboration and Web conferencing applications.


Session Initiation Protocol (SIP) Application Protocol

Describes the Session Initiation Protocol (SIP) Application Protocol. This protocol is a collection of independent proprietary client-server protocols that are used to provide enhanced functionality to Session Initiation Protocol (SIP)-based communication systems.


OC Authentication Web Service Protocol

Describes the OC Authentication Web Service Protocol. This protocol defines the message formats, protocol server behavior, and protocol client behavior for the purposes of authentication and certificate enrollment.


Web Service for E911 Support Protocol

Describes the Location Information Web Service interface that is used by protocol clients to retrieve locations associated with network identifiers, or locations within a city. A location is a civic address with up to room-level granularity. The network identifiers that can be specified are the Wireless Access Point, Received Signal Strength Indication, Media Access Control Address, Chassis, Port, Subnet, and Internet Protocol Address.


Extensible Chat Control Over Session Initiation Protocol (SIP)

Describes an XML-based protocol for transmitting data between Group Chat servers and Lync clients by using SIP INFO methods. In addition to transporting the chat messages, it provides support for chat room invitations, activity notifications, and posting of files.


Persistent Chat Web Protocol

Describes a protocol that provides a mechanism to allow the client of a persistent chat system to start an external chat room management web application.