Middleware and tools written in Erlang
OTP is a collection of useful middleware, libraries, and tools written in the Erlang programming language. It is an integral part of the open-source distribution of Erlang. The name OTP was originally an acronym for Open Telecom Platform, which was a branding attempt before Ericsson released Erlang/OTP as open source. However neither Erlang nor OTP is specific to telecom applications.[2][3]
The OTP distribution is supported and maintained by the OTP product unit at Ericsson, who released Erlang/OTP as open-source in the late 90s, to ensure its independence from a single vendor and to increase awareness of the language.
It contains:
History
Early days
Originally named Open System, it was started by Ericsson in late 1995 as a prototype system that aimed to select from a range of appropriate programming technologies and system components, including computers, languages, databases and management systems, to support a remote access system being developed at Ericsson.[5] In the same year, following the collapse of another gigantic C++-based project, Open System was ordered to provide support when it restarted from scratch using Erlang.[2] The result was the highly successful AXD301 system, a new ATM switch, announced in 1998. Open System system was later named Open Telecom Platform (OTP) when the first prototype was delivered in May 1996. OTP has also become a specific product unit within Ericsson since then, providing management, support and further development.
The early OTP system components in 1998:[5]
- Distributed application management
- SASL - error logging, release handling
- OS resource monitoring
- EVA - protocol independent event/alarm handling
- Mnesia - real-time active data replication
- SNMP - operations and maintenance interface
- INETS - simple HTTP support
A key subsystem in OTP is the System Architecture Support Libraries (SASL), which gave a framework for writing applications. The early version of SASL provided:[5]
- Start-up scripts
- An application concept
- Behaviours (design patterns)
- Error handling
- Debugging
- High-level software upgrade in runtime without shutdown
The behaviours provide programmers with yet higher abstractions for efficient program design. The early version included:[5]
OTP Components
The OTP components can be divided into six categories:[6]
- Basic Applications - Basic Erlang/OTP functionality.
- Compiler A compiler for Erlang modules.
- Kernel Functionality necessary to run Erlang/OTP itself.
- SASL (System Architecture Support Libraries) A set of tools for code replacement and alarm handling etc.
- Stdlib The standard library.
- Operations and Maintenance - OAM both of the system developed by the user and of Erlang/OTP itself.
- EVA A multi-featured event and alarm handler.
- OS_Mon A monitor which allows inspection of the underlying operating system.
- SNMP SNMP support including a MIB compiler and tools for creating SNMP agents.
- Interface and Communication - Interoperability and protocols support.
- Asn1 Support for ASN.1.
- Comet A library that enables Erlang/OTP to call COM objects on windows
- Crypto Cryptographical support
- Erl_Interface Low level interface to C.
- GS A graphics system used to write platform independent user interfaces.
- Inets A set of services such as a web server and a FTP client.
- Jinterface Low level interface to Java.
- SSL Secure Socket Layer (SSL), interface to UNIX BSD sockets
- Database Management.
- QLC Query language support for Mnesia DBMS.
- Mnesia A heavy duty real-time distributed database.
- ODBC ODBC database interface.
- CORBA services and IDL compiler.
- cosEvent Orber OMG Event Service.
- cosNotification Orber OMG Notification Service.
- cosTime Orber OMG Timer and TimerEvent Services.
- cosTransactions Orber OMG Transaction Service.
- IC IDL compiler
- Orber A CORBA object request broker.
- Tools.
- Appmon A utility used to view OTP applications.
- Debugger For debugging and testing of Erlang programs.
- Parsetools A set of parsing and lexical analysis tools.
- Pman A process manager used to inspect the state of an Erlang/OTP system.
- Runtime_Tools Tools to include in a production system.
- Toolbar A tool bar simplifying access to the Erlang/OTP tools.
- Tools A set of programming tools including a coverage analyzer etc.
- TV An ETS and Mnesia graphical table visualizer.
Applications in OTP
As of OTP 18.2, the following applications are included in the Erlang/OTP distribution:[7]
- asn1
- common_test
- compiler
- cosEvent
- cosEventDomain
- cosFileTransfer
- cosNotification
- cosProperty
- cosTime
- cosTransactions
- crypto
- debugger
- dialyzer
- diameter
- edoc
- eldap
- erl_docgen
- erl_interface
- erts
- et
- eunit
- gs
- hipe
- ic
- inets
/ 8 February 2024