Continually Improves Processes Through Standardization and Recognition
Standardization Process
Process standardization can be defined as the improvement of operational performance, cost reduction through decreased process errors, facilitation of communication, profiting from expert knowledge (Wüllenweber, Beimborn, Weitzel, & König, 2008, p.
From: Assistive Technology Service Delivery , 2019
Assistive technology techniques, tools, and tips
Anthony Shay , Marcia Scherer , in Assistive Technology Service Delivery, 2019
On Standardization
Process standardization can be defined as the improvement of operational performance, cost reduction through decreased process errors, facilitation of communication, profiting from expert knowledge (Wüllenweber, Beimborn, Weitzel, & König, 2008, p. 212), and providing flexibility without sacrificing organizational controls (Røhnebæk, 2012). By definition, standardization is a benefit to an organization. However, staff responses to these efforts are not always effective. Røhnebæk offers three ineffective responses to standardization efforts:
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Pragmatic ignorance: ignoring the fact that current standard operating procedures do not adequately address the current work conditions. The focus is on work tasks to the exclusion of process. In other words, the nose-to-the-grindstone approach;
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Compliance: involves increased stress as staff work to deal with the mismatch of the current situation with standard operating procedures. The tendency here is to redouble efforts to apply prescribed policy and procedures. This is the proverbial square peg pounded into the circular hole phenomenon;
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Adaptation: perceiving that standard operating procedures could be helpful but require some minor modifications. Resistance to standardization may lead to modifications to a prescribed process which leads to an overly complex system which makes managerial oversight problematic. This is the "road to perdition is paved with good intentions" approach (Røhnebæk, 2012, pp. 692–693).
Effective standardization is arrived at through addressing both tasks and processes and achieving a balance between them. The tasks staff are engaged in must reflect the contexts and actual circumstances within which they operate and engage the people with whom they work. Likewise, organizations develop standard operating procedures as a product of legislative oversight, ethical/best practices, as well as policies and procedures arrived at through evidence-based practices. Neither tasks nor processes are sacrificed one for the other.
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Video coding standards and formats
David R. Bull , Fan Zhang , in Intelligent Image and Video Compression (Second Edition), 2021
12.9.12 Performance gains for VVC over recent standards
As part of the standardization process, the VTM test model performance has been extensively compared with previous video coding standards. Table 12.11 summarizes comparison results between one of recent VTM versions (7.1) and the test models of HEVC (HM 16.20) and H.264/AVC (JM 19.0) based on the JVET common test conditions (in random access mode) using SDR test video content. It can be seen that VVC achieves an average bit rate saving of 32% over HEVC for these conditions. Coding gains are more significant on higher-resolution (2160p and 1080p) content. Fig. 12.32 shows example rate-distortion curves for three test codecs.
Video standard | Relative bit rate savings (%) against | |
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H.264/AVC | HEVC MP | |
Class A (2160p) | −70.0% | −39.0% |
Class B (1080p) | −65.1% | −35.3% |
Class C (480p) | −53.5% | −27.9% |
Class D (240p) | −50.0% | −26.0% |
Overall | −59.7% | −32.1% |
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Introduction
Erik Dahlman , ... Johan Sköld , in 4G LTE-Advanced Pro and The Road to 5G (Third Edition), 2016
1.4 Outline
The remainder of this book describes the technologies for the 4G and 5G wireless networks.
Chapter 2 describes the standardization process and relevant organizations such as the aforementioned 3GPP and ITU. The frequency bands available for mobile communication is also be covered, together with a discussion on the process for finding new frequency bands.
An overview of LTE and its evolution is found in Chapter 3. This chapter can be read on its own to get a high-level understanding of LTE and how the LTE specifications evolved over time. To underline the significant increase in capabilities brought by the LTE evolution, 3GPP introduced the names LTE-Advanced and LTE-Advanced Pro for some of the releases.
Chapters 4–11 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 cover the basic LTE structure, starting with the overall protocol structure in Chapter 4 and followed by a detailed description of the physical layer in Chapters 5–7 Chapter 5 Chapter 6 Chapter 7 . The remaining Chapters 8–11 Chapter 8 Chapter 9 Chapter 10 Chapter 11 , cover connection setup and various transmission procedures, including multi-antenna support.
Some of the major enhancements to LTE introduced over time is covered in Chapters 12–21 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18 Chapter 19 Chapter 20 Chapter 21 , including carrier aggregation, unlicensed spectrum, machine-type communication, and device-to-device communication. Relaying, heterogeneous deployments, broadcast/multicast services, dual connectivity multisite coordination are other examples of enhancements covered in these chapters.
RF requirements, taking into account spectrum flexibility and multi-standard radio equipment, is the topic of Chapter 22.
Chapters 23 and 24 Chapter 23 Chapter 24 cover the new radio access about to be standardized as part of 5G. A closer look on the requirements and how they are defined is the topic of Chapter 23, while Chapter 24 digs into the technical realization.
Finally, Chapter 25 concludes the book and the discussion on 5G radio access.
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Security
Magnus Olsson , ... Catherine Mulligan , in EPC and 4G Packet Networks (Second Edition), 2013
7.3.1 Access Security in E-UTRAN
It was clear from the start of the standardization process that E-UTRAN should provide a security level at least as high as that of UTRAN. Access security in E-UTRAN therefore consists of different components, similar to those that can be found in UTRAN:
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Mutual authentication between UE and network
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Key derivation to establish separate keys for ciphering and integrity protection
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Ciphering, integrity, and replay protection of NAS signaling between UE and MME
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Ciphering, integrity, and replay protection of RRC signaling between UE and eNB
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Ciphering of the user plane. The user plane is ciphered between UE and eNB
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Use of temporary identities in order to avoid sending the permanent user identity (IMSI) over the radio link.
Figure 7.2 illustrates some of these components in the network.
Below we will discuss in detail how each of these components has been facilitated.
The authentication procedure in E-UTRAN is in many ways similar to the authentication procedure in GERAN and UTRAN, but there are also differences. To understand the reason behind these differences, it is useful to first briefly look at the security features of GERAN and UTRAN systems. As with all security features in communication systems, what was considered sufficiently secure at one point in time may not turn out to be sufficient years later when attack methods and computing power have developed further. This is also true for 3GPP radio accesses. When GERAN was developed, some limitations were purposely accepted. For example, mutual authentication is not performed in GERAN where it is only the network that authenticates the terminal. It was thought that there was no need for the UE to authenticate the network, since it was unlikely that anyone would be able to set up a rogue GERAN network. When UTRAN/UMTS was developed, enhancements were made to avoid some of the limitations of GERAN. For example, mutual authentication was introduced. These new security procedures are one reason why a new type of SIM card was needed for UMTS: the so-called UMTS SIM (or USIM for short). With the introduction of E-UTRAN, further improvement is taking place. One important aspect is, however, that it has been agreed that the use of USIM in the terminal will be sufficient to access E-UTRAN – that is, no new type of SIM card is needed. The new features are instead supported by software in the terminal and the network.
Mutual authentication in E-UTRAN is based on the fact that both the USIM card and the network have access to the same secret key K. This is a permanent key that is stored on the USIM and in the HSS/AuC in the home operator's network. Once configured, the key K never leaves the USIM or the HSS/AuC. The key K is thus not used directly to protect any traffic and it is also not visible to the end-user or even the terminal. During the authentication procedure, other keys are generated from the key K in the terminal and in the network that are used for ciphering and integrity protection of user-plane and control-plane traffic. For example, one of the derived keys is used to protect the user plane, while another key is used to protect NAS signaling. One reason why several keys are produced like this is to provide key separation and to protect the underlying shared secret K. In UTRAN and GERAN, the same keys are used for ciphering of control signaling and user traffic, and hence this is also an enhancement compared to these earlier standards. This is, however, not the only key management enhancement, as will be discussed below.
The mechanism for authentication as well as session key generation in E-UTRAN is called EPS Authentication and Key Agreement (EPS AKA). Mutual authentication with EPS AKA is done in the same manner as for UMTS AKA, but as we will see when we go through the procedure, there are a few differences when it comes to key derivation.
EPS AKA is performed when the user attaches to EPS via E-UTRAN access. Once the MME knows the user's IMSI, the MME can request an EPS authentication vector (AV) from the HSS/AuC, as shown in Figure 7.3. Based on the IMSI, the HSS/AuC looks up the key K and a sequence number (SQN) associated with that IMSI. The AuC increases the SQN and generates a random challenge (RAND). Taking these parameters and the master key K as input to cryptographic functions, the HSS/AuC generates the UMTS AV. This AV consists of five parameters: an expected result (XRES), a network authentication token (AUTN), two keys (CK and IK), and the RAND. This is illustrated in Figure 7.3. Readers familiar with UMTS will recognize this Authentication Vector as the parameter that the HSS/AuC would send to the SGSN for access authentication in UTRAN. For E-UTRAN, however, the CK and IK are not sent to the MME. Instead, the HSS/AuC generates a new key, KASME, based on the CK and IK and other parameters such as the serving network identity (SN ID). The SN ID includes the Mobile Country Code (MCC) and Mobile Network Code (MNC) of the serving network. A reason for including SN ID is to provide a better key separation between different serving networks to prevent a key derived for one serving network being (mis)used in a different serving network. Key separation is illustrated in Figure 7.4.
KASME, together with XRES, AUTN, and RAND, constitutes the EPS AV that is sent to the MME. The CK and IK never leave the HSS/AuC when E-UTRAN is used. In order to distinguish the different AVs, the AUTN contains a special bit called the "separation bit" indicating whether the AV will be used for E-UTRAN or for UTRAN/GERAN. A reason for going through this extra step with the new key KASME, instead of using CK and IK for ciphering and integrity protection as in UTRAN, is to provide strong key separation for legacy GERAN/UTRAN systems. For more details on the generation of the EPS AV, see 3GPP TS 33.401.
Mutual authentication in E-UTRAN is performed using the parameters RAND, AUTN, and XRES. The MME keeps KASME and XRES but forwards RAND and AUTN to the terminal shown in Figure 7.5. Both RAND and AUTN are sent to the USIM. AUTN is a parameter calculated by the HSS/AuC based on the secret key K and the SQN. The USIM now calculates its own version of AUTN using its own key K and SQN, and compares it with the AUTN received from the MME. If they are consistent, the USIM authenticates the network. Then the USIM calculates a response RES using cryptographic functions with the key K and the challenge RAND as input parameters. The USIM also computes CK and IK in the same way as when UTRAN is used (it is, after all, a regular UMTS SIM card). When the terminal receives RES, CK, and IK from the USIM, it sends the RES back to the MME. The MME authenticates the terminal by verifying that the RES is equal to XRES. This completes the mutual authentication. The UE then uses the CK and IK to compute KASME in the same way as HSS/AuC did. If everything has worked out, the UE and network have authenticated each other and both UE and MME now have the same key KASME (note that none of the keys K, CK, IK, or KASME was ever sent between UE and the network).
Now all that remains is to calculate the keys to be used for protecting traffic. As mentioned above, the following type of traffic is protected between UE and E-UTRAN:
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NAS signaling between UE and MME
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RRC signaling between UE and eNB
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User-plane traffic between UE and eNB.
Different keys are used for each set of procedures above, and also different ciphering and integrity protection keys are used. The key KASME is used by UE and MME to derive the keys for ciphering and integrity protection of NAS signaling (KNASenc and KNASint). In addition, the MME also derives a key that is sent to the eNB (the KeNB). This key is used by the eNB to derive keys for ciphering of the user plane (KUPenc) as well as ciphering and integrity protection of the RRC signaling between UE and eNB (KRRCenc and KRRCint). The UE derives the same keys as eNB. The "family tree" of keys is typically referred to as a key hierarchy. The key hierarchy of E-UTRAN in EPS is illustrated in Figure 7.6.
Once the keys have been established in the UE and the network, it is possible to start ciphering and integrity protection of the signaling and user data. The standard allows use of different cryptographic algorithms for this, and the UE and the NW need to agree on which algorithm to use for a particular connection. The EPS encryption algorithms (EEA) currently supported for NAS, RRC, and UP ciphering are shown in Table 7.1. EEA0, 128-EEA1, and 128-EEA2 are mandatory to support in the UE, eNB, and MME, while 128-EEA3 is optional to support. The EPS integrity protection algorithms (EIA) currently supported for RRC and NAS signaling integrity protection are shown in Table 7.2. The algorithms 128-EIA1 and 128-EIA2 are mandatory to support in the UE, eNB, and MME, while 128-EIA3 is optional to support. The Null integrity protection algorithm EIA0 is only used for unauthenticated emergency calls. For more details on the ciphering and integrity algorithms supported with E-UTRAN, see 3GPP TS 33.401.
Name | Algorithm | Comment |
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EEA0 | Null ciphering algorithm | When this algorithm is selected, there is no ciphering of the messages. Supported from Release 8. |
128-EEA1 | SNOW 3G-based algorithm | Supported from Release 8 |
128-EEA2 | AES-based algorithm | Supported from Release 8 |
128-EEA3 | ZUC-based algorithm | Added in Release 11 |
Name | Algorithm | Comment |
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EIA0 | Null integrity protection algorithm | When this algorithm is selected, there is no integrity protection of the messages. Added in 3GPP Release 9 to support unauthenticated emergency calls |
128-EIA1 | SNOW 3G-based algorithm | Supported from Release 8 |
128-EIA2 | AES-based algorithm | Supported from Release 8 |
128-EIA3 | ZUC-based algorithm | Added in Release 11 |
The final aspect that should be mentioned is identity protection. In order to protect the permanent subscriber identity (i.e. IMSI) from being exposed in clear text over the radio interface, temporary identities are used whenever possible in a similar way to what is done in UTRAN. See the identities section in Chapter 6 for a description on how temporary identities are used in E-UTRAN.
A main enhancement in E-UTRAN as compared to UTRAN is, as was discussed above, the strong key separation between networks and key usage. A few other enhancements are also worth briefly mentioning:
- •
-
Larger key sizes. E-UTRAN supports not only 128-bit keys but can (in future deployments) also use 256-bit keys.
- •
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Additional protection against compromised base stations. Due to the flattened architecture in E-UTRAN, additional measures were added to protect against a potentially compromised "malicious" radio base station. One of the most important features is the added forward/backward security: each time the UE changes its point of attachment (due to mobility) or when the UE changes from the Idle to the Connected state, the air interface keys are updated according to a sophisticated procedure. This means that even in the unlikely event that the keys used so far have been compromised, security can be restored.
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Security
Magnus Olsson , ... Catherine Mulligan , in SAE and the Evolved Packet Core, 2010
7.3.2 Access security in E-UTRAN
It was clear from the start of the standardization process that E-UTRAN should provide a security level, at least as high as that of UTRAN. Access security in E-UTRAN therefore consists of different components, similar to those that can be found in UTRAN:
- •
-
Mutual authentication between UE and network.
- •
-
Key derivation to establish the keys for ciphering and integrity protection.
- •
-
Ciphering, integrity and replay protection of NAS signalling between UE and MME.
- •
-
Ciphering, integrity and replay protection of RRC signalling between UE and eNB.
- •
-
Ciphering of the user plane. The user plane is ciphered between UE and eNB.
- •
-
Use of temporary identities in order to avoid sending the permanent user identity (IMSI) over the radio link.
Figure 7.3.2.1 illustrates some of these components in the network.
Below we will discuss in detail how each of these components has been solved.
The authentication procedure in E-UTRAN is in many ways similar to the authentication procedure in GERAN and UTRAN but there are also differences. To understand the reason behind the differences, it is useful to first briefly look at the security features for GERAN and UTRAN systems. As with all security features in communication systems, what was considered sufficiently secure at one point in time may turn out not to be sufficient a few years later when attack methods and computing power have developed further. This is also true for 3GPP radio accesses. When GERAN was developed, some limitations were deliberately accepted. For example, mutual authentication is not performed in GERAN where it is only the network that authenticates the terminal. It was thought that there was no need for the UE to authenticate the network, since it was unlikely that anyone would be able to set up a rogue GERAN network. When UTRAN/UMTS was developed, enhancements were made to avoid some of the limitations of GERAN. For example, mutual authentication was introduced. These new security procedures are one reason why a new type of SIM card was needed for UMTS; the so called UMTS SIM (or USIM for short). With the introduction of E-UTRAN, further improvement is taking place. One important aspect is, however, that it has been agreed that the use of USIM in the terminal shall be sufficient to access E-UTRAN, that is, no new type of SIM card shall be needed. The new features are instead supported by software in the terminal and the network.
Mutual authentication in E-UTRAN is based on the fact that both the USIM card and the network have access to the same secret key K. This is a permanent key that is stored on the USIM and in the HSS/AuC in the home operator's network. Once configured, the key K never leaves the USIM or the HSS/AuC. The key K is thus not used directly to protect any traffic and it is also not visible to the end-user. During the authentication procedure, other keys are generated from the key K in the terminal and in the network that are used for ciphering and integrity protection of user plane and control plane traffic. For example, one of the derived keys is used to protect the user plane, while another key is used to protect the NAS signalling. One reason why several keys are produced like this is to provide key separation and to protect the underlying shared secret K. In UTRAN and GERAN, the same keys are used for control signalling and user traffic, and hence this is also an enhancement compared to these earlier standards. This is, however, not the only key management enhancement as will be discussed below.
The mechanism for authentication as well as key generation in E-UTRAN is called EPS Authentication and Key Agreement (EPS AKA). Mutual authentication with EPS AKA is done in the same manner as for UMTS AKA, but as we will see when we go through the procedure, there are a few differences when it comes to key derivation.
EPS AKA is performed when the user attaches to EPS via E-UTRAN access. Once the MME knows the user's IMSI, the MME can request an EPS authentication vector (AV) from the HSS/AuC as shown in Figure 7.3.2.2. Based on the IMSI, the HSS/AuC looks up the key K and a sequence number (SQN) associated with that IMSI. The AuC steps (i.e. increases) the SQN and generates a random challenge (RAND). Taking these parameters and the master key K as input to cryptographic functions, the HSS/AuC generates the UMTS AV. This AV consists of five parameters: an expected result (XRES), a network authentication token (AUTN), two keys (CK and IK), as well as the RAND. This is illustrated in Figure 7.3.2.3. Readers familiar with UMTS will recognize this Authentication Vector as the parameters that the HSS/AuC would send to the SGSN for access authentication in UTRAN. For E-UTRAN, however, the CK and IK are not sent to the MME. Instead the HSS/AuC generates a new key, KASME, based on the CK and IK and other parameters such as the serving network identity (SN ID). The SN ID includes the Mobile Country Code (MCC) and Mobile Network Code (MNC) of the serving network. A reason for including SN ID is to provide a better key separation between different serving networks to ensure that a key derived for one serving network cannot be (mis-) used in a different serving network. Key separation is illustrated in Figure 7.3.2.3.
The KASME together with XRES, AUTN and RAND constitutes the EPS AV that is sent to MME. The CK and IK never leave the HSS/AuC when E-UTRAN is used. In order to distinguish the different AVs, the AUTN contains a special bit called the 'separation bit' indicating whether the AV shall be used for E-UTRAN or for UTRAN/GERAN. A reason for going through this extra step with the new key KASME, instead of using CK and IK for ciphering and integrity protection like in UTRAN, is to provide a strong key separation towards legacy GERAN/UTRAN systems. For more details on the generation of the EPS AV, please see 3GPP TS 33.401 [33.401].
Mutual authentication in E-UTRAN is performed using the parameters RAND, AUTN and XRES. The MME keeps the KASME and XRES but forwards RAND and AUTN to the terminal shown in Figure 7.3.2.4. Both RAND and AUTN are sent to the USIM. AUTN is a parameter calculated by the HSS/AuC based on the secret key K and the SQN. The USIM now calculates its own version of AUTN using its own key K and SQN and compares it with the AUTN received from the MME. If they are consistent, the USIM has authenticated the network. Then the USIM calculates a response RES using cryptographic functions with the key K and the challenge RAND as input parameters. The USIM also computes CK and IK in the same way as when UTRAN is used (it is after all a regular UMTS SIM card). When the terminal receives RES, CK and IK from the USIM, it sends the RES back to the MME. The MME authenticates the terminal by verifying that the RES is equal to XRES. This completes the mutual authentication. The UE then uses the CK and IK to compute KASME in the same way as HSS/AuC did. If everything has worked out, the UE and network has authenticated each other and both UE and MME now have the same key KASME. (Note that none of the keys K, CK, IK or KASME was ever sent between UE and network.)
Now all that remains is to calculate the keys to be used for protecting traffic. As mentioned above, the following type of traffic is protected between UE and E-UTRAN:
- •
-
NAS signalling between UE and MME
- •
-
RRC signalling between UE and eNB
- •
-
User plane traffic between UE and eNB.
Different keys are used for each set of procedures above, and also different encryption and integrity protection keys are used. The key KASME is used by UE and MME to derive the keys for encryption and integrity protection of NAS signalling (KNASenc and KNASint). In addition, the MME also derives a key that is sent to the eNB (the KeNB). This key is used by the eNB to derive keys for encryption of the user plane (KUPenc) as well as encryption and integrity protection of the RRC signalling between UE and eNB (KRRCenc and KRRCint). The UE derives the same keys as eNB. The 'family tree' of keys is typically referred to as a key hierarchy. The key hierarchy of E-UTRAN in EPS is illustrated in Figure 7.3.2.5.
Once the keys have been established in the UE and the network it is possible to start ciphering and integrity protection of the signalling and user data. The standard allows use of different cryptographic algorithms for this and the UE and the NW need to agree on which algorithm to use for a particular connection. For more details on which ciphering and integrity algorithms are supported with E-UTRAN, please see 3GPP TS 33.401 [33.401].
The final aspect that should be mentioned is the identity protection. In order to protect the permanent subscriber identity (i.e. IMSI) from being exposed in clear text over the radio interface, temporary identities are used whenever possible in a similar way to what is done in UTRAN. Please see the identities section in Chapter 6 for a description on how temporary identities are used in E-UTRAN.
A main enhancement in E-UTRAN as compared to UTRAN is, as was discussed above, the strong key separation between networks and key-usage. A few other enhancements are also worth brief mentioning:
- •
-
Larger key sizes. E-UTRAN supports not only 128-bit keys but can (in future deployments) also use 256-bit keys.
- •
-
Additional protection against compromised base stations. Due to the flattened architecture in E-UTRAN, additional measures were added to protect against a potentially compromised 'malicious' radio base station. One of the most important features is the added forward/backward security: each time the UE changes its point of attachment (due to mobility), or, when the UE changes from IDLE to ACTIVE, the air interface keys are updated according to a sophisticated procedure. This means that even in the unlikely event that the keys used so far have been compromised, security can be restored.
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NR initial access
Weijie Xu , ... Li Guo , in 5G NR and Enhancements, 2022
6.3.1.4 Length of NR preamble sequence
The length of preamble sequence was also intensively discussed in the standardization process of 3GPP. For the macrocell scenario in the FR1, Ref. [15] showed that a preamble using long sequence (sequence length is 839) has better performance than a preamble with short sequence and large SCS. Ref. [16] also pointed out that the NR system in the FR1 should strive to provide similar cell coverage and system capacity as LTE. A long sequence is necessary to provide sufficient RACH preamble capacity. Therefore NR supports a preamble sequence with a length of 839, which is the same as LTE.
For the FR2, a shorter preamble sequence should be adopted to restrict the bandwidth occupied by the PRACH channel. Regarding the PRACH capacity in the FR2 system, the method of configuring multiple PRACH resources that are FDMed in the frequency domain can be utilized to increase the capacity. During the standardization discussion, two choices for the length of short sequences, 139 and 127, were discussed. The major benefit of adopting 127 is that it can support the UE to apply a mask code of M sequence on top of the ZC sequence and thus the PRACH capacity is increased. However, the PRACH capacity in the FR2 system can be resolved by allocating more frequency resources for PRACH channel. Furthermore, one drawback of adopting 127 is the Peak to Average Power Ratio (PAPR) is increased due to adding the mask of the M sequence to the ZC sequence. Therefore the length for short sequence was determined to be 139 [17].
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A Survey on Smart Grid Communications: From an Architecture Overview to Standardization Activities
Periklis Chatzimisios , ... Georgios Stavrou , in Handbook of Green Information and Communication Systems, 2013
26.5 Standards and Interoperability
A general definition of interoperability is "the ability of two or more systems or components to exchange information, to use the information that has been exchanged, and to work cooperatively to perform a task." Interoperability in the smart grid addresses the development of a novel open architecture of technologies and systems, described as a system of systems for the smart grid that allows the interaction among various systems and technologies involved in order to provide a functional model for the smart grid. The realization of the smart grid includes capabilities and technology deployments that must connect large numbers of smart devices and systems involving hardware and software. Interoperability enables integration, effective cooperation, and two-way communication among the many interconnected elements of the electric power grid [35]. In order to achieve interoperability internationally recognized communication and interface standards should be developed by standards development organizations (SDOs) and specification setting organizations (SSOs).
In particular, SDOs operate under similar (participation and balloting) rules worldwide. Often many standards begin their "life" as de facto ("something that exists in fact but not as a matter of law") standards and SDOs actually author de jure ("something that exists by operation of law") standards. In addition to SDOs another two entities exist, "alliances" and "user groups." A differentiator between user groups, standardization organizations, and alliances is that user groups' rules often permit more free discussion between those actually using standards and specifications than those of the developing organizations.
The establishment of interoperable smart grid standards and protocols is required because a large number of smart grid projects worldwide are currently underway and many devices are being widely deployed in such systems. However, there is a major dilemma between "doing it fast" by working out standards that can guide developing technologies and enable competition against prompt world players like China [36] and "doing it right" by building standards that reflect industry needs while protecting stakeholder interests. In any case, utilities and vendors often move forward whether or not the standards exist or have been finalized since many times the lag time in developing standards is inevitable.
Interoperability standards require much effort by both vendors and users and every participating entity in the standardization process [37] since they should include:
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Recognition of the need for standards in a particular area.
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Involvement of users to develop the business scenarios and use cases that drive the requirements for the standard.
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Clear definition of the scope and purpose of the standard.
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Review of existing standards in order to determine whether or not they meet the needs (even with minor modifications or selection of options).
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Development of a draft standard based on the users' requirements as well as the technology experience of the vendors.
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Widespread review and pilot implementations of the draft standard to resolve ambiguities, imprecise requirements, and incomplete functionality.
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Finalization of the standard and full implementation of the standard by vendors.
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Significant interoperability testing of the standard by different vendors under different scenarios.
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Amending or updating the standard in order to reflect findings during the interoperability tests.
26.5.1 Standardization Activities around the World
The effective development and operation of the smart grid requires many sets of standards to be in place. The United States, Canada, China, South Korea, Australia, and the European Community (EC) countries are conducting research and development on smart grid applications and technologies. The concepts differ greatly in the main regions and this is also reflected in the respective roadmaps and studies by the various international, national, and regional attempts.
Many standards bodies, including the National Institute of Standards and Technology (NIST), International Electrotechnical Commission (IEC), Institute of Electrical and Electronic Engineers (IEEE), Internet Engineering Task Force (IETF), American National Standards Institute (ANSI), North American Reliability Corporation (NERC), and World Wide Web Consortium (W3C) are tackling these interoperability issues for a broad range of industries, including the power industry, the electronics industry, and the telecommunications sector.
The following are the main standardization bodies that perform various activities towards achieving the goal of interoperability in the implementation of the smart grid.
26.5.1.1 IEEE
The Institute of Electrical and Electronics Engineers (IEEE) (http://www.ieee.org ) is an international nonprofit, professional organization for the advancement of technology. It has the most members of any technical professional organization in the world, with more than 365,000 members in around 150 countries. Most IEEE members are electrical engineers, computer engineers, and computer scientists, but the organization's wide scope of interests has attracted engineers in other disciplines. The IEEE Standards Association (IEEE-SA) is a leading global developer of standards with more than 20,000 individual and corporate participants in the standardization process.
IEEE has a similar but more flexible methodology to that of the IEC for developing (draft and final) standards by implementing a voting process by members of the corresponding Working Groups. Additionally, IEEE Working Groups develop many other types of documents (including recommended practices, technical reports, conference, and journal papers, as well as other non-standards-oriented documents). The IEEE Power and Energy Society (PES) is currently serving as the world's largest forum about the latest and most exciting technological developments in the electric power industry. The IEEE Communications Society (ComSoc) and the IEEE Society on Social Implications of Technology (SSIT) are also are actively engaged in developing and promoting smart grid technologies.
Although IEEE has more than 100 standards (either finalized or under development) relevant to the smart grid, it is working closely with the National Institute of Standards and Technology (NIST). In particular, IEEE adopted the NIST smart grid Conceptual Model, which provides a high-level framework that defines seven important smart grid domains; Bulk Generation, Transmission, Distribution, Customers, Operations, Markets, and Service Providers. In particular, IEEE views smart grid as a large "system of systems," whereas each NIST smart grid domain is expanded into three smart grid foundational layers (the Power and Energy Layer, the Communication Layer and the IT/Computer Layer) [38].
26.5.1.2 NIST
The National Institute of Standards and Technology (NIST) (http://www.nist.gov/smartgrid) is a nonregulatory federal agency within the U.S. Department of Commerce that promotes U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life. The Energy Independence and Security Act (EISA) of 2007 [39] has assigned to the National Institute of Standards and Technology (NIST) the primary responsibility to coordinate development of a framework that includes protocols and model standards for information management to achieve interoperability of smart grid devices and systems [39]. There are two primary bodies within NIST designated with tackling this task: the Smart Grid Advisory Committee (composed of 15 industry players) and the Smart Grid Interoperability Panel (a public forum composed of all stakeholders).
In January 2010, NIST released a report that included about 80 initial interoperability standards as well as 14 "Priority Action Plans" to address gaps in the standards. NIST Special Publication 1108 [40] describes a roadmap for the standards on smart grid interoperability. In particular, it presents the expected functions and services in the smart grid as well as the application and requirement of communication networks in the implementation of the smart grid. Furthermore, NIST Report 7628 [41] particularly focuses on the information security issues of the smart grid by presenting the critical security challenges and specifying the security requirements in the smart grid.
In response to the urgent need to establish interoperable standards and protocols for the smart grid, NIST developed a three-phase plan:
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Phase 1: Accelerate the setup of a primary set of standards by identifying applicable standards and requirements, gaps in current standards, and priorities for supplementary standardization activities. This phase includes the engagement of stakeholders in a participatory public process.
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Phase 2: Establish a robust Smart Grid Interoperability Panel (SGIP) to drive longer-term progress by maintaining the development of the additional standards that will be needed in the future.
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Phase 3: Develop and implement a framework for conformity testing and certification targeting to ensure interoperability and security under realistic operating conditions of the defined smart grid standards.
The Smart Grid Interoperability Panel has several priority-specific Committees and Working Groups such as [40]:
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Smart Grid Architecture Committee (SGAC): Maintains a conceptual reference model for the smart grid and develops corresponding high-level architectural principles and requirements.
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Smart Grid Testing and Certification Committee (SGTCC): Creates and maintains the necessary framework for compliance, interoperability, and cyber security testing and certification for recommended smart grid standards.
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Cyber Security Working Group (CSWG): Identifies and analyzes security requirements and develops a risk mitigation strategy to ensure the security and integrity of the smart grid.
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Domain Expert Working Groups (DEWGs): NIST has been working to address interoperability through the following groups [42]:
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Transmission and Distribution (T&D)
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Building to Grid (B2G)
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Industry to Grid (I2G)
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Home to Grid (H2G)
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Business and Policy (B&P)
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Vehicle to Grid (V2G)
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Cyber Security (CS)
Priority Action Plans (PAPs): Many standards require revision or enhancement and new standards need to be developed to fill gaps and issues for which resolution is most urgently needed. Thus, in order to address these PAPs were established and can be found in Table 26.1 (new PAPs are added as necessary).
Priority Action Plan (PAP) | Standard(s) or Guideline(s) |
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PAP 0—Meter Upgradeability Standard | NEMA Meter Upgradeability Standard |
PAP 1—Role of IP in the Smart Grid | Informational IETF RFC |
PAP 2—Wireless Communications for the Smart Grid | IEEE 802.x, 3GPP, 3GPP2, ATIS, TIA |
PAP 3—Common Price Communication Model | OASIS EMIX, ZigBee SEP 2, NAESB |
PAP 4—Common Scheduling Mechanism | OASIS WS-Calendar |
PAP 5—Standard Meter Data Profiles | AEIC V2.0 Meter Guidelines (addressing use of ANSI C12) |
PAP 6—Common Semantic Model for Meter Data Tables | ANSI C12.19-2008, MultiSpeak V4, IEC 61968-9 |
PAP 7—Electric Storage Interconnection Guidelines | IEEE 1547.4, IEEE 1547.7, IEEE 1547.8, IEC 61850-7-420, ZigBee SEP 2 |
PAP 8—CIM for Distribution Grid Management | IEC 61850-7-420, IEC 61968-3-9, IEC 61968-13,14, MultiSpeak V4, IEEE 1547 |
PAP 9—Standard DR and DER Signals | NAESB WEQ015, OASIS EMIX, OpenADR, ZigBee SEP 2 |
PAP 10—Standard Energy Usage Information | NAESB Energy Usage Information, OpenADE, ZigBee SEP 2, IEC 61968-9, ASHRAE SPC 201P |
PAP 11—Common Object Models for Electric Transportation | ZigBee SEP 2, SAE J1772, SAE J2836/1-3, SAE J2847/1-3, ISO/IEC 15118-1,3, SAE J2931, IEEE P2030-2, IEC 62196 |
PAP 12—IEC 61850 Objects/DNP3 Mapping | IEC 61850-80-5, Mapping DNP to IEC 61850, DNP3 (IEEE 1815) |
PAP 13—Time Synchronization, IEC 61850 Objects/IEEE C37.118 Harmonization | IEC 61850-90-5, IEEE C37.118, IEEE C37.238, Mapping IEEE C37.118 to IEC 61850, IEC 61968-9 |
PAP 14—Transmission and Distribution Power Systems Model Mapping | IEC 61968-3, MultiSpeak V4 |
PAP 15—Harmonize Power Line Carrier Standards for Appliance Communications in the Home | DNP3 (IEEE 1815), HomePlug AV, HomePlug C&C, IEEE P1901 and P1901.2, ISO/IEC 12139-1, G.9960 (G.hn/PHY), G.9961 (G.hn/DLL), G.9972 (G.cx), G.hnem, ISO/IEC 14908-3, ISO/IEC 14543, EN 50065-1 |
PAP 16—Wind Plant Communications | IEC 61400-25 |
PAP 17—Facility Smart Grid Information Standard | New Facility Smart Grid Information Standard ASHRAE SPC 201P |
PAP 18—SEP 1.x to SEP 2 Transition and Coexistence | ZigBee |
The smart grid will ultimately require hundreds of standards. Some are more urgently needed than others. To prioritize its work, NIST chose to focus on six key functionalities plus cyber security and network communications. These functionalities are especially critical to ongoing and near-term deployments of smart grid technologies and services, and they include the priorities recommended by the Federal Energy Regulatory Commission (FERC) in its policy statement as follows [40]:
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Demand response and consumer energy efficiency
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Wide-area situational awareness
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Energy storage
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Electric transportation
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Advanced Metering Infrastructure (AMI)
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Distribution grid management
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Network communications
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Cyber security
26.5.1.3 IEC
The International Electrotechnical Commission (IEC) (http://www.iec.ch) is a nonprofit, nongovernmental international standards organization that prepares and publishes international standards for all electrical, electronic, and related technologies, including technologies for power generation, transmission, and distribution. The IEC Council consists of National Committees (NCs), one from each country that is a member of the IEC. Under the IEC Council are Standards Management Boards (SMBs), which coordinate the international standards work. This standards work is performed through many Technical Councils (TCs), each tasked with specific areas. The Standardization Management Board (SMB) of the IEC resolved the establishment of a Strategic Group on Smart Grids (Strategic Group 3), which submitted a roadmap for its own standards and high-level recommendations that were especially relevant to the European standardization roadmap [43].
26.5.1.4 CENELEC
The European Telecommunications Standards Institute (ETSI), together with the European Committee for Standardization (Comité Européen Normalization—CEN) and the European Committee for Electrotechnical Standardization (CENELEC) have formed a Joint Working Group for Smart Grid standardization efforts and recently published a roadmap about the European Commission's policy for the smart grid [44].
26.5.1.5 ANSI
The private, nonprofit American National Standards Institute (ANSI) (http://www.ansi.org) oversees the creation, spread, and use of norms and guidelines that directly impact businesses in nearly every sector, including energy distribution. The ANSI itself does not develop standards, but instead facilitates the development of American National Standards (ANS) by accrediting the procedures of standards developing organizations.
26.5.1.6 SGCC
The State Grid Corporation of China (SGCC) has defined its own smart grid standardization roadmap [45] by taking into account several existing standardization roadmaps e.g., IEC SG 3, NIST Interoperability Roadmap, IEEE P2030, CEN/CENELEC/ETSI Working Groups, German DKE Roadmap, and Japanese METI Roadmap.
26.5.1.7 UCA International Users Group
The UCA International Users Group (UCAIug) (http://www.ucaiug.org) is a nonprofit corporation focused on enabling utility integration through the deployment of open standards. UCAIug does not write standards but it works closely with those bodies that have primary responsibility for the completion of standards. In particular, the Open Smart Grid (OpenSG) subcommittee sponsors working groups to address smart grid related requirements and interoperability guidelines development.
26.5.1.8 Vendor Collaborations
Many collaborations and alliances of vendors have been initiated to resolve the details of standards and to develop vendor agreements for standard implementation and product interoperability. Some relevant vendor alliances and collaborations include [46]:
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HomePlug Powerline Alliance (www.homeplug.org)
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Z-Wave Alliance (www.z-wavealliance.org)
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ZigBee Alliance (www.zigbee.org)
Several other major smart grid standardization roadmaps and studies that are worthy of mention are:
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German Standardization Roadmap E-Energy/Smart Grid [47]
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International Telecommunication Union (ITU-T) Smart Grid Focus Group [48]
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Japanese Industrial Standards Committee (JISC) roadmap to international standardization for smart grid [49]
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Korea's Smart Grid Roadmap 2030 from the Ministry of Knowledge Economy (MKE) [50]
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CIGRE D2.24 [51]
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Microsoft SERA [52]
Furthermore, various national roadmaps exist, for example from Spain [53], Austria [54], and the UK [55]. Those national roadmaps are either still under development or do not recommend specific standards (a detailed study of the above and an overview of other SG roadmaps can be found in [4] and [5]).
26.5.2 A Report on Smart Grid Standards
This subsection presents the main standards for smart grid communications and security. Table 26.2 provides a list of the smart grid standards, specifications, requirements, and guidelines identified as the most important for smart grid communications. The second list, Table 26.3, contains the corresponding smart grid security standards and documents. Furthermore, Table 26.4 provides a list of additional smart grid communications and security standards, specifications, requirements, guidelines, and reports subject to further review and consensus development.
Standards/Specifications/Requirements/Guidelines | Short Description |
ANSI/ASHRAE 135-2010/ISO 16484-5 BACnet | Data communication protocol for building automation and control networks |
ANSI C12.21/IEEE P1702/MC1221 | Transport of measurement device data over telephone networks |
ANSI/CEA 709 and Consumer Electronics Association (CEA) 852.1 LON Protocol Suite | A general purpose local area networking protocol |
ANSI/CEA 709.1-B-2002 Control Network Protocol Sp. | A specific physical layer protocol designed for use with ANSI/CEA 709.1-B-2002 |
ANSI/CEA 709.2-A R-2006 Control Network Power Line | A specific physical layer protocol designed for use with ANSI/CEA 709.1-B-2002 |
ANSI/CEA 709.3 R-2004 | A specific physical layer protocol designed for use with ANSI/CEA 709.1-B-2002 |
ANSI/CEA-709.4:1999 Fiber-Optic Channel Specification | A protocol that provides a way to tunnel local operating network messages |
IEEE Std 1815-2010 | Substation and feeder device automation, communications between control centers and substations |
IEC 60870-6 / Telecontrol Application Service Element 2 | Defines the messages sent between control centers of different utilities |
IEC 61850 Suite | Defines communication within transmission/distribution substations for automation & protection |
IEC 61968/61970 Suites | Defines information exchanged among control center systems using common information models |
IEEE C37.118-2005 | Phasor measurement unit (PMU) performance specifications and communications for synchrophasor data |
IEEE 1547 Suite | Physical and electrical interconnections between utilities and distributed generation and storage |
IEEE 1588 | Standard for time management and clock synchronization across the smart grid for equipment needing consistent time management |
RFC 6272, Internet Protocols for the Smart Grid | Internet protocols for IP-based smart grid networks |
IEEE 1901-2010 , ITU-T G.9972 | Both IEEE 1901-2010 and ITU-T G.9972 specify intersystem protocol (ISP)-based broadband PLC coexistence mechanisms for home networking |
NISTIR 7761, NIST Guidelines for Assessing Wireless Standards for Smart Grid Applications | A draft of key tools and methods to assist smart grid system designers in making informed decisions about existing and emerging wireless technologies |
OPC-UA Industrial | A platform-independent specification for a secure, reliable, high-speed data exchange based on a publish/subscribe mechanism |
Open Geospatial Consortium Geography Markup Language (GML) | Exchange of location-based information addressing geographic data requirements for many smart grid applications |
Smart Energy Profile 2.0 | Home area network (HAN) device communications and information model |
OpenHAN | A specification for a home area network (HAN) to connect to the utility advanced metering system including device communication, measurement, and control |
SAE J2836/1: Use Cases for Communication Between Plug-in Vehicles and the Utility Grid | Establishes use cases for communication between plug-in electric vehicles and the electric power grid, for energy transfer and other applications |
SGTCC Interoperability Process Reference Manual (IPRM) | Outlines the conformance, interoperability, and cyber security testing and certification requirements for SGIP-recommended smart grid standards |
Security Profile for Advanced Metering Infrastructure, v 1.0, Advanced Security Acceleration Project—Smart Grid | Provides guidance and security controls to organizations developing or implementing AMI solutions |
Department of Homeland Security (DHS), National Cyber Security Division Catalog of Control Systems Security: Recommendations for Standards Developers | Presents a compilation of practices that various industry bodies have recommended to increase the security of control systems from both physical and cyber attacks |
DHS Cyber Security Procurement Language for Control Systems | Provides guidance to procuring cyber security technologies for control systems products and services |
IEC 62351 Parts 1-8 | Defines information security for power system control operations |
IEEE 1686-2007 | Defines the functions and features to be provided in substation intelligent electronic devices (IEDs) to accommodate critical infrastructure protection programs |
NERC Critical Infrastructure Protection (CIP) 002-009 | Covers organizational, processes, physical, and cyber security standards for the bulk power system |
NIST Special Publication (SP) 800-53 | Covers cyber security standards and guidelines for federal information systems, including those for the bulk power system |
NISTIR 7628 Guidelines for Smart Grid Cyber Security | Guidelines that include an overview of the cyber security strategy used by the CSWG, an evaluative framework for assessing risks to smart grid components and systems, and a guide to assist organizations as they craft a smart grid cyber security strategy |
ANSI C12.22-2008/IEEE P1703/MC1222 | End device tables communications over any network |
CableLabs PacketCable Security Monitoring and Automation Architecture Technical Report | Describes a broad range of services that could be provided over television cable, including remote energy management |
IEC 61400-25 | Communication and control of wind power plants |
ITU Recommendation G.9960/G.9661 (G.hn) | In-home broadband home networking over power lines, phone lines, and coaxial cables |
IEEE P1901 | Broadband communications over power lines: MAC and physical layer (PHY) protocols |
IEEE P1901.2 and ITU-T G.9955/G.9956 (G.hnem) | Low frequency narrowband communications over power lines |
ISO/IEC 12139-1 | High-speed power line communications (PLC), medium access control (MAC), and physical layer (PHY) protocols |
IEEE 802 family | Includes standards developed by the IEEE 802 LAN/MAN Standards Committee |
TIA TR-45/3GPP2 family of standards | Standards for cdma2000® Spread Spectrum and High Rate Packet Data Systems |
3GPP family of standards (including 2G, 3G, and 4G) | 2G, 3G, and 4G cellular network protocols for packet delivery |
ETSI GMR-1 3G family of standards | GMR-1 3G is a satellite-based packet service equivalent to 3GPP standards |
ISA SP100 | Wireless communication standards intended to provide reliable and secure operation |
Network management standards such as DMTF, CIM, WBEM, SNMPv3, netconf, STD 62, CMIP/CMIS | Protocols used for management of network components and devices attached to the network |
ASHRAE 201P Facility Smart Grid Information Model | Enable appliances/control systems in homes/buildings/industrial facilities to manage electrical loads and generation sources and to communicate information to utility and electrical service providers |
NIST SP 500-267 | A profile for IPv6 in the U.S. Government |
Z-wave | A wireless mesh networking protocol for home area networks |
IEEE P2030, IEEE P2030.1, IEEE P2030.2 | IEEE smart grid series of standards |
IEC 62056 Device Language Message Specification/Companion Specification for Energy Metering | Energy metering communications |
IEC 60870-2-1 | Telecontrol equipment and systems—Part 2: Operating conditions—Section 1: Power supply and electromagnetic compatibility |
IEEE 1613 | Standard Environmental and Testing Requirements for Communications Networking Devices in Electric Power Substations |
IEEE P1775/1.9.7 | Standard for Power Line Communication Equipment |
ISO/IEC 15045 | Specification for a residential gateway connecting home network domains to other network domains |
ISA SP99 | Cyber security mitigation for industrial and bulk power generation stations |
ISO 27000 | A series of ISO standards for information security matters |
NIST FIPS 140-2 | U.S. government computer security standard used to accredit cryptographic modules |
OASIS WS-Security and suite of security standards | Toolkit for building secure, distributed applications, applying a wide range of security technologies |
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Introduction to fabric testing
J. Hu , in Fabric Testing, 2008
Japanese Industrial Standards
Japanese Industrial Standards (JIS) specifies the standards used for industrial activities in Japan. The standardization process is coordinated by the Japanese Industrial Standards Committee and published through the Japanese Standards Association. The JIS in many ways has been Japan's answer to ISO. The JIS is extremely sophisticated and complex and goes beyond the requirements of the ISO 9000 series but essentially performs the same quality management function. The JIS is more rigorous and comprehensive in standards, making it extremely challenging for an organization to successfully implement. This fact has led to its adoption almost exclusively in Japan and makes its requirement outside Japan very rare. Organizations that have a JIS certification can be considered to be at least as good as if not better than an organization that has an ISO 9000 certification, with most JIS systems being closer in scope to ISO 9001.
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Towards the Real-Time Modeling of the Heart
R.R. Rama , S. Skatulla , in Advances in Biomechanics and Tissue Regeneration, 2019
8.5.2.1.1 Coarse Template Discretization
Making use of the BV heart model introduced in Section 8.5.2 , the application of the cube template standardization process is first investigated. As described in Section 8.5.1.1, the cube grid is constructed in such a way that it encompassed all the heart models, hence ensuring that all data would be captured by the grid. It is discretized with a constant spacing along every coordinate direction, resulting in a total of 294 template nodes, as shown in Fig. 8.29.
The entire PODI calculation takes on average a total time of about 4 min. This calculation time includes reading the dataset from the database, projecting the results from the hearts to the grid, setting up interpolants, carrying out the PODI calculation, projecting the PODI results from the grid back to the heart of the problem at hand, and postprocessing the results. The costliest operation is projecting the results from the dataset heart geometries to the template grid, and from the grid back to the heart geometry of the problem at hand. This procedure requires about 3.80 min, that is, 95% of the total calculation time. On the other hand, the actual reduced order calculation only needs 0.26 s, where the displacement field computation across all 58 time steps lasts for only 0.029 s. This shows that subsecond calculations can be achieved, as the displacement calculation frequency is about 2000 Hz. This calculation frequency is higher than the one recorded in Rama et al. [34] because the number of template nodes is less here, resulting in smaller dataset matrices, U i .
The -norm is found to be 0.46 for the displacement field, 0.89 for the strain field, and 0.98 for the stress field. For the pressure-volume relationship curve, the errors are 0.23 and 0.22 for the LV and the RV, respectively. These errors are higher than those presented in Rama et al. [34] and the final deformed configuration exhibits nonphysical deformations. Solution fields, such as the displacement field shown in Fig. 8.30B, are not smooth, as opposed to the corresponding full-scale simulation result depicted in Fig. 8.30A. The main reason why those nonsmooth solution fields are obtained is that, as explained in Section 8.5.1.1, some of the entries in U i refer to template nodes, which are located outside the respective model and have been assigned a default zero-value for all solution fields. However, these template nodes need to be included because for other datasets, they are positioned inside the model. Consequently, the projection process leads to solution fields of low magnitude near those nodes, as is clearly visible in Fig. 8.30B.
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Wind Energy
John K. Kaldellis , in Comprehensive Renewable Energy (Second Edition), 2022
2.01.3.11 Chapter 12
The main scope of Chapter 12 is to describe testing procedures of new wind turbines along with the well-established standardization processes. Additionally, emphasis is given on discussing the major safety issues as well as any manufacturing, installation and operational issues related to the safe operation of wind turbines, designating coherence between these elements. Accordingly, the various international standards (mostly IEC) related to design aspects for large and small wind turbines onshore and offshore, and testing of power performance, mechanical loads, acoustic noise, power quality and safety are described, while on top of that, the various certification schemes are also examined. Finally, a presentation is included, concerning the organizations involved in the formal testing, standardization and certification procedures for both existing and new wind turbines and wind parks.
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