Google Wave Federation Protocol
Encyclopedia
The Google Wave Federation Protocol, renamed as Wave Federation Protocol, is an open protocol, extension of the Extensible Messaging and Presence Protocol
(XMPP) that is used in Apache Wave. It is designed for near real-time
communication between the computer supported cooperative work
wave servers.
, communication is possible regardless of provider. For instance, organizations can operate as wave providers for their members, an individual can run a private wave server for a single user or family members, and an Internet service provider can run a wave service as another Internet service for its users as a supplement to email, IM
, FTP, etc. In this model, Google Wave is one of many wave providers.
Java
source code for the "Google Wave Federation Prototype Server" was released in a Mercurial
repository in July 2009 under the Apache License
2.0.
(DNS) SRV record
s, and TLS authentication and encryption
of connections. The XMPP transport encrypts operations at a transport level. So, it only provides cryptographic security between servers connected directly to each other. An additional layer of cryptography provides end-to-end authentication between wave providers using cryptographic signatures and certificates, allowing all wavelet providers to verify the properties of the operation. Therefore, a downstream wave provider can verify that the wave provider is not spoofing wavelet operations. It should not be able to falsely claim that a wavelet operation originated from a user on another wave provider or that it was originated in a different context. This addresses the situation where two users from different, trustworthy wave providers are participants of a wavelet that is hosted on a malicious provider. The protocol requires each participant to sign its user's operations with its own certificate. The signatures of all the operations forwarded by the host will be evaluated by the participants. This is to stop malicious hosts from altering or spoofing the contents of the messages from the user of other services. All the signatures and verifications are done by the wave providers, not the client software of the end users.
All waves and wavelets (child waves) are identified by a globally unique wave id, which is a domain name and an id string. The domain name identifies the wave provider where the wave originated. Waves and wavelets are hosted by the wave provider of the creator. Wavelets in the same wave can be hosted by different wave providers. However, user data is not federated; i.e., not shared with other wave providers. Private reply wavelets are also possible, of which other participants have no knowledge or access. If a private wavelet is sent between users on the same wave provider, it's not federated regardless of where the parent wave is hosted.
and writes and reads wavelet operations to and from the wave store. Typically, the wave service serves waves to users of the wave provider which connect to the wave service frontend. For the purpose of federation, the wave service shares waves with participants from other providers by communicating with these wave provider's servers. Copies of wavelets are distributed to all wave providers that have participants in a given wavelet. Copies of a wavelet at a particular provider can either be local or remote. We use the term to refer to these two types of wavelet copies (in both cases, we are referring to the wavelet copy, and not the wavelet). A wave view can contain both local and remote wavelet copies simultaneously.
The originating wave server is responsible for the hosting and the processing of wavelet operations submitted by local participants and by remote participants from other wave providers. The wave server performs concurrency control by ordering the submitted wavelet operations relative to each other using operational transformation. It also validates the operations before applying them to a local wavelet.
Remote wavelets are hosted by other providers, cached and updated with wavelet operations that the local provider gets from the remote host. When a local participant submits a wavelet operation to a remote wavelet, the wave server forwards the operation to the wave server of the hosting provider. Then the transformed and applied operation is echoed back and applied to the cached copy.
Wave services use federation gateways and a federation proxy
components to communicate and share waves with other wave providers. Federation gateways communicate local wavelet operations, push new local wavelet operations to the remote wave providers of any other participants, fulfill requests for old wavelet operations, and process wavelet operations submission requests. A Federation proxy communicates remote wavelet operations and is the component of a wave provider that communicates with the federation gateway of remote providers. It receives new wavelet operations pushed to it from other providers, requests old wavelet operations, and submits wavelet operations to other providers.
Extensible Messaging and Presence Protocol
Extensible Messaging and Presence Protocol is an open-standard communications protocol for message-oriented middleware based on XML . The protocol was originally named Jabber, and was developed by the Jabber open-source community in 1999 for near-real-time, extensible instant messaging , presence...
(XMPP) that is used in Apache Wave. It is designed for near real-time
Real-time computing
In computer science, real-time computing , or reactive computing, is the study of hardware and software systems that are subject to a "real-time constraint"— e.g. operational deadlines from event to system response. Real-time programs must guarantee response within strict time constraints...
communication between the computer supported cooperative work
Computer supported cooperative work
The term computer-supported cooperative work was first coined by Irene Greif and Paul M. Cashman in 1984, at a workshop attended by individuals interested in using technology to support people in their work. At about this same time, in 1987 Dr...
wave servers.
Overview
Still currently in development, the Wave Federation Protocol is an open protocol that is intended to parallel the openness of the email protocol so waves may succeed email as the dominant form of Internet communication.Availability
Since the protocol is open, anyone can become a wave provider and share waves with others. Like emailEmail
Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient both be online at the...
, communication is possible regardless of provider. For instance, organizations can operate as wave providers for their members, an individual can run a private wave server for a single user or family members, and an Internet service provider can run a wave service as another Internet service for its users as a supplement to email, IM
Instant messaging
Instant Messaging is a form of real-time direct text-based chatting communication in push mode between two or more people using personal computers or other devices, along with shared clients. The user's text is conveyed over a network, such as the Internet...
, FTP, etc. In this model, Google Wave is one of many wave providers.
Java
Java (programming language)
Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...
source code for the "Google Wave Federation Prototype Server" was released in a Mercurial
Mercurial
Mercurial is a cross-platform, distributed revision control tool for software developers. It is mainly implemented using the Python programming language, but includes a binary diff implementation written in C. It is supported on Windows and Unix-like systems, such as FreeBSD, Mac OS X and Linux...
repository in July 2009 under the Apache License
Apache License
The Apache License is a copyfree free software license authored by the Apache Software Foundation . The Apache License requires preservation of the copyright notice and disclaimer....
2.0.
Framework
Some features of Extensible Messaging and Presence Protocol inherited by the wave federation protocol are the discovery of IP addresses and port numbers, using Domain Name SystemDomain name system
The Domain Name System is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities...
(DNS) SRV record
SRV record
A Service record is a specification of data in the Domain Name System defining the location, i.e. the hostname and port number, of servers for specified services. It is defined in RFC 2782, and its type code is 33...
s, and TLS authentication and encryption
Transport Layer Security
Transport Layer Security and its predecessor, Secure Sockets Layer , are cryptographic protocols that provide communication security over the Internet...
of connections. The XMPP transport encrypts operations at a transport level. So, it only provides cryptographic security between servers connected directly to each other. An additional layer of cryptography provides end-to-end authentication between wave providers using cryptographic signatures and certificates, allowing all wavelet providers to verify the properties of the operation. Therefore, a downstream wave provider can verify that the wave provider is not spoofing wavelet operations. It should not be able to falsely claim that a wavelet operation originated from a user on another wave provider or that it was originated in a different context. This addresses the situation where two users from different, trustworthy wave providers are participants of a wavelet that is hosted on a malicious provider. The protocol requires each participant to sign its user's operations with its own certificate. The signatures of all the operations forwarded by the host will be evaluated by the participants. This is to stop malicious hosts from altering or spoofing the contents of the messages from the user of other services. All the signatures and verifications are done by the wave providers, not the client software of the end users.
All waves and wavelets (child waves) are identified by a globally unique wave id, which is a domain name and an id string. The domain name identifies the wave provider where the wave originated. Waves and wavelets are hosted by the wave provider of the creator. Wavelets in the same wave can be hosted by different wave providers. However, user data is not federated; i.e., not shared with other wave providers. Private reply wavelets are also possible, of which other participants have no knowledge or access. If a private wavelet is sent between users on the same wave provider, it's not federated regardless of where the parent wave is hosted.
Concurrent federation
A wave provider operates a wave service on one or more networked servers. The central pieces of the wave service is the wave store, which stores wavelet operations, and the wave server, which resolves wavelet operations by operational transformationOperational transformation
Operational transformation is a technology for supporting a range of collaboration functionalities in advanced groupware systems. OT was originally invented for consistency maintenance and concurrency control in collaborative editing of plain text documents...
and writes and reads wavelet operations to and from the wave store. Typically, the wave service serves waves to users of the wave provider which connect to the wave service frontend. For the purpose of federation, the wave service shares waves with participants from other providers by communicating with these wave provider's servers. Copies of wavelets are distributed to all wave providers that have participants in a given wavelet. Copies of a wavelet at a particular provider can either be local or remote. We use the term to refer to these two types of wavelet copies (in both cases, we are referring to the wavelet copy, and not the wavelet). A wave view can contain both local and remote wavelet copies simultaneously.
The originating wave server is responsible for the hosting and the processing of wavelet operations submitted by local participants and by remote participants from other wave providers. The wave server performs concurrency control by ordering the submitted wavelet operations relative to each other using operational transformation. It also validates the operations before applying them to a local wavelet.
Remote wavelets are hosted by other providers, cached and updated with wavelet operations that the local provider gets from the remote host. When a local participant submits a wavelet operation to a remote wavelet, the wave server forwards the operation to the wave server of the hosting provider. Then the transformed and applied operation is echoed back and applied to the cached copy.
Wave services use federation gateways and a federation proxy
Proxy server
In computer networks, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server...
components to communicate and share waves with other wave providers. Federation gateways communicate local wavelet operations, push new local wavelet operations to the remote wave providers of any other participants, fulfill requests for old wavelet operations, and process wavelet operations submission requests. A Federation proxy communicates remote wavelet operations and is the component of a wave provider that communicates with the federation gateway of remote providers. It receives new wavelet operations pushed to it from other providers, requests old wavelet operations, and submits wavelet operations to other providers.
See also
- Web 2.0Web 2.0The term Web 2.0 is associated with web applications that facilitate participatory information sharing, interoperability, user-centered design, and collaboration on the World Wide Web...
- XMLXMLExtensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
- Extensible Messaging and Presence ProtocolExtensible Messaging and Presence ProtocolExtensible Messaging and Presence Protocol is an open-standard communications protocol for message-oriented middleware based on XML . The protocol was originally named Jabber, and was developed by the Jabber open-source community in 1999 for near-real-time, extensible instant messaging , presence...
- Novell PulseNovell PulseNovell Vibe is an real time collaborative editing software platform under development from Novell released in April 2011. The software is one of the first major developments outside Google to utilize the Google Wave Federation Protocol...