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77-512: DECT-2020 NR has new capabilities compared to DECT and DECT Evolution: The DECT-2020 standard has been designed to co-exist in the DECT radio band with existing DECT deployments. It uses the same Time Division slot timing and Frequency Division center frequencies and uses pre-transmit scanning to minimize co-channel interference. DECT NR+ (called DECT-2020 NR in ETSI ) primarily focuses on addressing

154-472: A datagram . Both protocols use a header field for indicating the source and destination port numbers. The port numbers are encoded in the transport protocol packet header , and they can be readily interpreted not only by the sending and receiving hosts but also by other components of the networking infrastructure. In particular, firewalls are commonly configured to differentiate between packets based on their source or destination port numbers. Port forwarding

231-509: A man-in-the-middle attack impersonating a DECT base station and revert to unencrypted mode – which allows calls to be listened to, recorded, and re-routed to a different destination. After an unverified report of a successful attack in 2002, members of the deDECTed.org project actually did reverse engineer the DECT Standard Cipher in 2008, and as of 2010 there has been a viable attack on it that can recover

308-404: A network address such as an IP address , and a port number. This is known as binding . A socket is used by a process to send and receive data via the network. The operating system's networking software has the task of transmitting outgoing data from all application ports onto the network, and forwarding arriving network packets to processes by matching the packet's IP address and port number to

385-409: A connection endpoint and to direct data to a specific service. At the software level, within an operating system , a port is a logical construct that identifies a specific process or a type of network service . A port at the software level is identified for each transport protocol and address combination by the port number assigned to it. The most common transport protocols that use port numbers are

462-531: A domestic DECT Generic Access Profile (GAP) system include multiple handsets to one base station and one phone line socket. This allows several cordless telephones to be placed around the house, all operating from the same telephone jack. Additional handsets have a battery charger station that does not plug into the telephone system. Handsets can in many cases be used as intercoms , communicating between each other, and sometimes as walkie-talkies , intercommunicating without telephone line connection. DECT operates in

539-400: A means for a portable phone or "Portable Part" to access a fixed telephone network via radio. Base station or "Fixed Part" is used to terminate the radio link and provide access to a fixed line. A gateway is then used to connect calls to the fixed network, such as public switched telephone network (telephone jack), office PBX, ISDN, or VoIP over Ethernet connection. Typical abilities of

616-476: A received signal strength indication (RSSI) list. When a new channel is required, the mobile terminal (PP) or base station (FP) selects a channel with the minimum interference from the RSSI list. The maximum allowed power for portable equipment as well as base stations is 250 mW. A portable device radiates an average of about 10 mW during a call as it is only using one of 24 time slots to transmit. In Europe,

693-475: A related but distinct concept, namely the internal address of an endpoint used only within the node. On March 26, 1972, Vint Cerf and Jon Postel called for documenting the then-current usages and establishing a socket number catalog in RFC 322. Network administrators were asked to submit a note or place a phone call, "describing the function and socket numbers of network service programs at each HOST". This catalog

770-519: A running application. For this purpose, port numbers lower than 1024 identify the historically most commonly used services and are called the well-known port numbers . Higher-numbered ports are available for general use by applications and are known as ephemeral ports . Ports provide a multiplexing service for multiple services or multiple communication sessions at one network address. In the client–server model of application architecture, multiple simultaneous communication sessions may be initiated for

847-554: A series of port connections (knocks) from a client computer to enable a server connection. An example of the use of ports is the delivery of email . A server used for sending and receiving email generally needs two services. The first service is used to transport email to and from other servers. This is accomplished with the Simple Mail Transfer Protocol (SMTP). A standard SMTP service application listens on TCP port 25 for incoming requests. The second service

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924-427: A socket. For TCP, only one process may bind to a specific IP address and port combination. Common application failures, sometimes called port conflicts , occur when multiple programs attempt to use the same port number on the same IP address with the same protocol. Applications implementing common services often use specifically reserved well-known port numbers for receiving service requests from clients. This process

1001-499: A standard that Postel had published in May 1972 in RFC 349, in which he first proposed official assignments of port numbers to network services and suggested a dedicated administrative function, which he called a czar , to maintain a registry. The 256 values of the AEN were divided into the following ranges: The Telnet service received the first official assignment of the value 1. In detail,

1078-572: A suggestion by Enrico Tosato of Italy, to reflect its broader range of application including data services. In 1995, due to its more global usage, the name was changed from European to Enhanced. DECT is recognized by the ITU as fulfilling the IMT-2000 requirements and thus qualifies as a 3G system. Within the IMT-2000 group of technologies, DECT is referred to as IMT-2000 Frequency Time (IMT-FT). DECT

1155-460: A user's computer or another mail server. While the listening port number of a server is well defined (IANA calls these the well-known ports), the client's port number is often chosen from the dynamic port range (see below). In some applications, the clients and the server each use specific port numbers assigned by the IANA. A good example of this is DHCP in which the client always uses UDP port 68 and

1232-413: A variation of DECT called DECT 6.0 , using a slightly different frequency range, which makes these units incompatible with systems intended for use in other areas, even from the same manufacturer. DECT has almost completely replaced other standards in most countries where it is used, with the exception of North America. DECT was originally intended for fast roaming between networked base stations, and

1309-557: A wide-area DECT network known as "Fido" after much regulatory delay, covering major cities in Italy. The service was promoted for only a few months and, having peaked at 142,000 subscribers, was shut down in 2001. DECT has been used for wireless local loop as a substitute for copper pairs in the "last mile" in countries such as India and South Africa. By using directional antennas and sacrificing some traffic capacity, cell coverage could extend to over 10 kilometres (6.2 mi). One example

1386-468: Is a 5G data transmission protocol which meets ITU-R IMT-2020 requirements for ultra-reliable low-latency and massive machine-type communications, and can co-exist with earlier DECT devices. The DECT standard was developed by ETSI in several phases, the first of which took place between 1988 and 1992 when the first round of standards were published. These were the ETS 300-175 series in nine parts defining

1463-619: Is a cordless telephony standard maintained by ETSI . It originated in Europe , where it is the common standard, replacing earlier standards, such as CT1 and CT2 . Since the DECT-2020 standard onwards, it also includes IoT communication. Beyond Europe, it has been adopted by Australia and most countries in Asia and South America . North American adoption was delayed by United States radio-frequency regulations. This forced development of

1540-437: Is an example application of this. The practice of attempting to connect to a range of ports in sequence on a single host is commonly known as port scanning . This is usually associated either with malicious cracking attempts or with network administrators looking for possible vulnerabilities to help prevent such attacks. Port connection attempts are frequently monitored and logged by hosts. The technique of port knocking uses

1617-542: Is avoided, each base station can provide up to 120 channels in the DECT spectrum before frequency reuse. Each timeslot can be assigned to a different channel in order to exploit advantages of frequency hopping and to avoid interference from other users in asynchronous fashion. DECT allows interference-free wireless operation to around 100 metres (110 yd) outdoors. Indoor performance is reduced when interior spaces are constrained by walls. DECT performs with fidelity in common congested domestic radio traffic situations. It

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1694-448: Is generally immune to interference from other DECT systems, Wi-Fi networks, video senders , Bluetooth technology, baby monitors and other wireless devices. ETSI standards documentation ETSI EN 300 175 parts 1–8 (DECT), ETSI EN 300 444 (GAP) and ETSI TS 102 527 parts 1–5 (NG-DECT) prescribe the following technical properties: The DECT physical layer uses FDMA/TDMA access with TDD. Gaussian frequency-shift keying (GFSK) modulation

1771-406: Is involved. By keeping the entities separate, the handset is capable of responding to any combination of entity traffic, and this creates great flexibility in fixed network design without breaking full interoperability. DECT GAP is an interoperability profile for DECT. The intent is that two different products from different manufacturers that both conform not only to the DECT standard, but also to

1848-455: Is known as listening , and involves the receipt of a request on the well-known port potentially establishing a one-to-one server-client dialog, using this listening port. Other clients may simultaneously connect to the same listening port; this works because a TCP connection is identified by a tuple consisting of the local address, the local port, the remote address, and the remote port. The well-known ports are defined by convention overseen by

1925-626: Is possible with a mesh network topology. In October 2021, DECT-2020 NR was approved for the IMT-2020 standard, for use in Massive Machine Type Communications (MMTC) industry automation, Ultra-Reliable Low-Latency Communications (URLLC), and professional wireless audio applications with point-to-point or multicast communications; the proposal was fast-tracked by ITU-R following real-world evaluations. The new protocol will be marketed as NR+ (New Radio plus) by

2002-533: Is security is based on AES with key length of 128 bits. Integrity protection is based on same algorithm and key length NR+ does not define the key distribution mechanism "the number of key-pairs and the key distribution is outside of the scope of the present document" although it has been studied The DECT technical committee has started specification work for Release 2 of the standard in June 2023. DECT Digital Enhanced Cordless Telecommunications ( DECT )

2079-541: Is supported by the DECT forum. The New Generation DECT (NG-DECT) standard, marketed as CAT-iq by the DECT Forum, provides a common set of advanced capabilities for handsets and base stations. CAT-iq allows interchangeability across IP-DECT base stations and handsets from different manufacturers, while maintaining backward compatibility with GAP equipment. It also requires mandatory support for wideband audio . DECT-2020 New Radio, marketed as NR+ (New Radio plus),

2156-533: Is the corDECT standard. The first data application for DECT was Net wireless LAN system by Olivetti, launched in 1993 and discontinued in 1995. A precursor to Wi-Fi, Net was a micro-cellular data-only network with fast roaming between base stations and 520 kbit/s transmission rates. Data applications such as electronic cash terminals, traffic lights, and remote door openers also exist, but have been eclipsed by Wi-Fi , 3G and 4G which compete with DECT for both voice and data. The DECT standard specifies

2233-563: Is used: the binary one is coded with a frequency increase by 288 kHz, and the binary zero with frequency decrease of 288 kHz. With high quality connections, 2-, 4- or 8-level differential PSK modulation (DBPSK, DQPSK or D8PSK), which is similar to QAM-2, QAM-4 and QAM-8, can be used to transmit 1, 2, or 3 bits per each symbol. QAM-16 and QAM-64 modulations with 4 and 6 bits per symbol can be used for user data (B-field) only, with resulting transmission speeds of up to 5,068   Mbit/s. DECT provides dynamic channel selection and assignment;

2310-579: Is usually either the Post Office Protocol (POP) or the Internet Message Access Protocol (IMAP) which is used by email client applications on users' personal computers to fetch email messages from the server. The POP service listens on TCP port number 110. Both services may be running on the same host computer, in which case the port number distinguishes the service that was requested by a remote computer, be it

2387-444: The #Co-Existence with Classic DECT . To do this, FT devices periodically scan the radio channel they operate on, and map busy time slots measured to be in use assuming it is an on-going Classic DECT connection. FT devices allocate the channel access time for the child devices on free time slots, preserving error free communications on the busy slots time slots. Channel access allocations are sent in beacon messages to all devices in

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2464-509: The Internet Assigned Numbers Authority (IANA). In many operating systems special privileges are required for applications to bind to these ports because these are often deemed critical to the operation of IP networks. Conversely, the client end of a connection typically uses a high port number allocated for short-term use, therefore called an ephemeral port . IANA is responsible for the global coordination of

2541-632: The Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP); those port numbers are 16-bit unsigned numbers . A port number is always associated with a network address of a host , such as an IP address , and the type of transport protocol used for communication. It completes the destination or origination address of a message. Specific port numbers are reserved to identify specific services so that an arriving packet can be easily forwarded to

2618-419: The internet of things (IoT). The DECT standard includes the generic access profile (GAP), a common interoperability profile for simple telephone capabilities, which most manufacturers implement. GAP-conformance enables DECT handsets and bases from different manufacturers to interoperate at the most basic level of functionality, that of making and receiving calls. Japan uses its own DECT variant, J-DECT, which

2695-579: The 1880–1900 MHz band and defines ten frequency channels from 1881.792 MHz to 1897.344 MHz with a band gap of 1728 kHz. DECT operates as a multicarrier frequency-division multiple access (FDMA) and time-division multiple access (TDMA) system. This means that the radio spectrum is divided into physical carriers in two dimensions: frequency and time. FDMA access provides up to 10 frequency channels, and TDMA access provides 24 time slots per every frame of 10   ms. DECT uses time-division duplex (TDD), which means that down- and uplink use

2772-518: The DECT Forum to support IP-DECT functions in home gateway / IP-PBX equipment. The ETSI TS 102 527 series comes in five parts and covers wideband audio and mandatory interoperability features between handsets and base stations. They were preceded by an explanatory technical report, ETSI TR 102 570. The DECT Forum maintains the CAT-iq trademark and certification program; CAT-iq wideband voice profile 1.0 and interoperability profiles 2.0/2.1 are based on

2849-473: The DECT Forum. OFDMA and SC-FDMA modulations were also considered by the ESTI DECT committee. OpenD is an open-source framework designed to provide a complete software implementation of DECT ULE protocols on reference hardware from Dialog Semiconductor and DSP Group ; the project is maintained by the DECT forum. The DECT standard originally envisaged three major areas of application: Of these,

2926-399: The DECT protocol make it hard to intercept a frame, modify it and send it later again, as DECT frames are based on time-division multiplexing and need to be transmitted at a specific point in time. Unfortunately very few DECT devices on the market implemented authentication and encryption procedures  – and even when encryption was used by the phone, it was possible to implement

3003-452: The DECT reserved radio bands 1, 2 and 9, in the frequency range of 1880-1930 MHz. DECT reserved radio bands are license free, but devices need to pass certification ensuring correct operation on the bands. NR+ supports 3 topologies NR+ Mesh network is based on a clustered tree In all these network topologies the NR+ assumes that a device, called FT node , manages the radio resource usage in

3080-612: The DNS root, IP addressing, and other protocol resources. This includes the registration of commonly used TCP and UDP port numbers for well-known internet services. The port numbers are divided into three ranges: the well-known ports , the registered ports , and the dynamic or private ports . The well-known ports (also known as system ports ) are those numbered from 0 through 1023. The requirements for new assignments in this range are stricter than for other registrations. The registered ports are those from 1024 through 49151. IANA maintains

3157-577: The GAP profile defined within the DECT standard, are able to interoperate for basic calling. The DECT standard includes full testing suites for GAP, and GAP products on the market from different manufacturers are in practice interoperable for the basic functions. The DECT media access control layer includes authentication of handsets to the base station using the DECT Standard Authentication Algorithm (DSAA). When registering

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3234-458: The GSM protocol, but also includes elements unique to DECT. Unlike the GSM protocol, the DECT network specifications do not define cross-linkages between the operation of the entities (for example, Mobility Management and Call Control). The architecture presumes that such linkages will be designed into the interworking unit that connects the DECT access network to whatever mobility-enabled fixed network

3311-426: The NR+ mesh network to Internet. All the devices autonomously measure parent FT device's radio link quality, and can switch to another FT device if a better link or shorter route to sink is available. Similarly, if a parent device is not acknowledging messages, or is not sending the periodic beacon advertisement, a device will look for alternative parents. The mesh network heals itself in error situations and changes in

3388-524: The NR+ network nodes. It is analogous to ports in UDP or TCP protocol. Like UDP and TCP, CVG offers both unreliable and reliable messaging services, datagram or flow control service and segmentation and reassembly for messages. Convergence layer provides security with encryption and integrity protection of messages end-to-end in the NR+ network. Data link control layer is the message routing service for NR+ networks. Routing decisions are done in each device in

3465-481: The U.S. with only minimal changes. These channels are reserved exclusively for voice communication applications and therefore are less likely to experience interference from other wireless devices such as baby monitors and wireless networks . The New Generation DECT ( NG-DECT ) standard was first published in 2007; it was developed by ETSI with guidance from the Home Gateway Initiative through

3542-501: The air interface, and ETS 300-176 defining how the units should be type approved. A technical report, ETR-178, was also published to explain the standard. Subsequent standards were developed and published by ETSI to cover interoperability profiles and standards for testing. Named Digital European Cordless Telephone at its launch by CEPT in November 1987; its name was soon changed to Digital European Cordless Telecommunications, following

3619-480: The choice of transmission frequency and time slot is always made by the mobile terminal. In case of interference in the selected frequency channel, the mobile terminal (possibly from suggestion by the base station) can initiate either intracell handover, selecting another channel/transmitter on the same base, or intercell handover, selecting a different base station altogether. For this purpose, DECT devices scan all idle channels at regular 30   s intervals to generate

3696-473: The cluster or link it controls. The Point-to-point and star networks enable dedicated links, with reserved capacity for scheduled transmissions. A leaf node, called PT node in NR+, can ask for certain resource reservation for it when it associates to the FT node. As this reservation can be done only for the next link, Mesh networking with multiple relaying links in the path relies on random access channel usage where

3773-478: The cluster. MAC layer also provides link scope encryption and integrity protection. Physical layer uses Cyclic prefix version of OFDM as the core technology. The technologies provide well-known behaviour in challenging radio conditions. PHY layer provides error detection to higher layers, Forward error correction and HARQ with soft combining . Received messages with errors are combined with re-transmissions, making it possible to decode correct message even if

3850-505: The devices needing to communicate compete for the access window defined by the FT node. This increases the communication delays in Mesh. The benefits of mesh networking network topology and operation are robustness for changes or errors and coverage extension. Robustness is the result of the autonomous decisions of the devices. There is no single point of failure. NR+ also supports having multiple gateway devices, called Sinks , connecting

3927-590: The domestic application (cordless home telephones) has been extremely successful. The enterprise PABX market, albeit much smaller than the cordless home market, has been very successful as well, and all the major PABX vendors have advanced DECT access options available. The public access application did not succeed, since public cellular networks rapidly out-competed DECT by coupling their ubiquitous coverage with large increases in capacity and continuously falling costs. There has been only one major installation of DECT for public access: in early 1998 Telecom Italia launched

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4004-726: The first DECT product was Net wireless LAN. However, its most popular application is single-cell cordless phones connected to traditional analog telephone , primarily in home and small-office systems, though gateways with multi-cell DECT and/or DECT repeaters are also available in many private branch exchange (PBX) systems for medium and large businesses, produced by Panasonic , Mitel , Gigaset , Ascom , Cisco , Grandstream , Snom , Spectralink , and RTX. DECT can also be used for purposes other than cordless phones, such as baby monitors , wireless microphones and industrial sensors. The ULE Alliance 's DECT ULE and its "HAN FUN" protocol are variants tailored for home security, automation, and

4081-583: The first set of assignments was: In the early ARPANET, the AEN was also called a socket name , and was used with the Initial Connection Protocol (ICP), a component of the Network Control Protocol (NCP). NCP was the forerunner of the modern Internet protocols. Today the terminology service name is still closely connected with port numbers, the former being text strings used in some network functions to represent

4158-460: The following protocol entities: Optionally it may also contain others: All these communicate through a Link Control Entity (LCE). The call control protocol is derived from ISDN DSS1 , which is a Q.931 -derived protocol. Many DECT-specific changes have been made. The mobility management protocol includes the management of identities, authentication, location updating, on-air subscription and key allocation. It includes many elements similar to

4235-426: The handset on the base, both record a shared 128-bit Unique Authentication Key (UAK). The base can request authentication by sending two random numbers to the handset, which calculates the response using the shared 128-bit key. The handset can also request authentication by sending a 64-bit random number to the base, which chooses a second random number, calculates the response using the shared key, and sends it back with

4312-456: The higher layers. The DECT data link layer uses Link Access Protocol Control (LAPC), a specially designed variant of the ISDN data link protocol called LAPD. They are based on HDLC . GFSK modulation uses a bit rate of 1152 kbit/s, with a frame of 10   ms (11520   bits) which contains 24 time slots. Each slots contains 480 bits, some of which are reserved for physical packets and

4389-488: The key. In 2012, an improved authentication algorithm, the DECT Standard Authentication Algorithm 2 (DSAA2), and improved version of the encryption algorithm, the DECT Standard Cipher 2 (DSC2), both based on AES 128-bit encryption, were included as optional in the NG-DECT/CAT-iq suite. Port (computer networking) In computer networking , a port or port number is a number assigned to uniquely identify

4466-487: The necessary features of low latency and high reliability. This makes it suitable for applications requiring real-time audio transmission and performance as required by professional audio systems. DECT NR+ technology is specified by DECT committee in the ETSI . The specifications for NR+ are called DECT-2020 in ETSI. An important design criteria for NR+ was to co-exist with Classic DECT communications. This allows NR+ to use

4543-473: The needs of local area deployments for two use case areas: massive Machine Type Communication (mMTC) and Ultra-Reliable Low Latency Communication (URLLC) as defined for 5G networks application areas . The release 1 of the standard targets several applications within these use cases, including Smart Metering and Smart grid , Industrial internet of things , Building automation , and Professional audio DECT NR+ decentralized and autonomous networking capability

4620-497: The network advertisement beacons. This extends the coverage for each FT device that joins the network. Overall description of the technology and protocol layers are provided in the DECT-2020 New Radio (NR); Part 1: Overview; Release 1 specification Convergence layer offers identification and multiplexing of the traffic of different applications and services using the NR+ communications. CVG operates end-to-end between

4697-422: The network, there is no central routing table. DLC routing operates in 3 modes: Unicast, multicast and broadcast routing is supported. As the NR+ network has internal routing and addresses it can operate without Internet Protocol routing services. Internet protocols can be carried in NR+ networks. Medium access control main services are radio resource control and data transfer. Radio resource control ensures

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4774-421: The network. Each device added to the network may act as a FT device, extending the network coverage. The sinks are configured first and start advertising the network in beacon messages. Devices scan radio channels, and associate to the parent they hear advertising the network and cluster. Associated devices can act as FT devices, and extend the network by selecting a channel with least traffic and start forwarding

4851-450: The official list of well-known and registered ranges. The dynamic or private ports are those from 49152 through 65535. One common use for this range is for ephemeral ports . Transport-layer protocols , such as the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP), transfer data using protocol data units (PDUs). For TCP, the PDU is a segment , and for UDP it is

4928-404: The power limit was expressed as effective radiated power (ERP), rather than the more commonly used equivalent isotropically radiated power (EIRP), permitting the use of high-gain directional antennas to produce much higher EIRP and hence long ranges. The DECT media access control layer controls the physical layer and provides connection oriented , connectionless and broadcast services to

5005-420: The re-transmission too contained errors. NR+ radio can operate on frequencies below 6 GHz. Standard defined speeds are up to gigabits per second. Radio implementations of course vary in the speeds achieved and frequencies supported. NR+ defines message encryption and integrity protection in both CVG and MAC layers. Encryption and integrity protection use own separate keys on the 2 layers. The encryption

5082-572: The relevant parts of ETSI TS 102 527. The DECT Ultra Low Energy (DECT ULE) standard was announced in January 2011 and the first commercial products were launched later that year by Dialog Semiconductor . The standard was created to enable home automation , security, healthcare and energy monitoring applications that are battery powered. Like DECT, DECT ULE standard uses the 1.9 GHz band, and so suffers less interference than Zigbee , Bluetooth , or Wi-Fi from microwave ovens, which all operate in

5159-432: The rest is guard space. Slots 0–11 are always used for downlink (FP to PP) and slots 12–23 are used for uplink (PP to FP). There are several combinations of slots and corresponding types of physical packets with GFSK modulation: The 420/424 bits of a GFSK basic packet (P32) contain the following fields: The resulting full data rate is 32 kbit/s, available in both directions. The DECT network layer always contains

5236-408: The same frequency but different time slots. Thus a base station provides 12 duplex speech channels in each frame, with each time slot occupying any available channel – thus 10 × 12 = 120 carriers are available, each carrying 32 kbit/s. DECT also provides frequency-hopping spread spectrum over TDMA /TDD structure for ISM band applications. If frequency-hopping

5313-401: The same service. For TCP and UDP, a port number is a 16-bit unsigned integer, thus ranging from 0 to 65535. For TCP, port number 0 is reserved and cannot be used, while for UDP, the source port is optional and a value of zero means no port . A process associates its input or output channels via an internet socket , which is a type of file descriptor , associated with a transport protocol ,

5390-457: The second random number. The standard also provides encryption services with the DECT Standard Cipher (DSC). The encryption is fairly weak , using a 35-bit initialization vector and encrypting the voice stream with 64-bit encryption. While most of the DECT standard is publicly available, the part describing the DECT Standard Cipher was only available under a non-disclosure agreement to the phones' manufacturers from ETSI . The properties of

5467-597: The server always uses UDP port 67. Port numbers are sometimes seen in web or other uniform resource locators (URLs). By default, HTTP uses port 80 and HTTPS uses port 443, but a URL like http://www.example.com:8080/path/ specifies that the web browser connects instead to port 8080 of the HTTP server. The concept of port numbers was established by the early developers of the ARPANET in informal cooperation of software authors and system administrators. The term port number

5544-676: The unlicensed 2.4 GHz ISM band . DECT ULE uses a simple star network topology, so many devices in the home are connected to a single control unit. A new low-complexity audio codec, LC3plus , has been added as an option to the 2019 revision of the DECT standard. This codec is designed for high-quality voice and music applications such as wireless speakers, headphones, headsets, and microphones. LC3plus supports scalable 16-bit narrowband, wideband, super wideband, fullband, and 24-bit high-resolution fullband and ultra-band coding, with sample rates of 8, 16, 24, 32, 48 and 96 kHz and audio bandwidth of up to 48 kHz. DECT-2020 New Radio protocol

5621-731: Was developed by ETSI but has since been adopted by many countries all over the World. The original DECT frequency band (1880–1900 MHz) is used in all countries in Europe . Outside Europe, it is used in most of Asia , Australia and South America . In the United States , the Federal Communications Commission in 2005 changed channelization and licensing costs in a nearby band (1920–1930 MHz, or 1.9  GHz ), known as Unlicensed Personal Communications Services (UPCS), allowing DECT devices to be sold in

5698-476: Was not yet in use. It was preceded by the use of the term socket number in the early development stages of the network. A socket number for a remote host was a 40-bit quantity. The first 32 bits were similar to today's IPv4 address, but at the time the most-significant 8 bits were the host number. The least-significant portion of the socket number (bits 33 through 40) was an entity called Another Eightbit Number , abbreviated AEN. Today, network socket refers to

5775-600: Was published in July 2020; it defines a new physical interface based on cyclic prefix orthogonal frequency-division multiplexing (CP- OFDM ) capable of up to 1.2   Gbit/s transfer rate with QAM -1024 modulation. The updated standard supports multi-antenna MIMO and beamforming , FEC channel coding , and hybrid automatic repeat request . There are 17 radio channel frequencies in the range from 450   MHz up to 5,875   MHz, and channel bandwidths of 1,728, 3,456, or 6,912   kHz. Direct communication between end devices

5852-574: Was specifically designed for Metering and Smart Grid applications, and mesh networking application in general. The technology can scale up to millions of devices within a single network. The low latency communications URLLC is suitable for various use cases of Industry 4.0 . These applications encompass robotics, monitoring and predictive maintenance and others. NR+ supports these use cases through its low latency and high reliability, dedicated frequency band, and high density and scalability Regarding Professional Audio and PMSE applications, DECT NR+ offers

5929-463: Was subsequently published as RFC 433 in December 1972 and included a list of hosts and their port numbers and the corresponding function used at each host in the network. This first registry function served primarily as documentation of usage and indicated that port number usage was conflicting between some hosts for "useful public services". The document promised a resolution of the conflicts based on

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