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Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
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3

Core Network Technologies

The Core Network Technologies group at the Communications Technology Laboratory (CTL) has two major thrusts, each of which addresses both timely and long-term critical aspects of computer networking. The Emerging Network Technologies program develops metrology, test, and measurement techniques to support new disruptive network technologies, including 5G/6G core networks, quantum networking, and information-centric networks. The Trustworthy Networks Research program concentrates on technologies necessary to increase the security, resilience, and performance of the protocols underpinning the Internet. This includes resolving systemic vulnerabilities in existing and emerging critical network infrastructures and developing new architectures and protocols to improve the trustworthiness of future networks.

OVERALL DISCUSSION

The quantum networking programs have continued to produce notable results through their transition into CTL from other areas of the National Institute of Standards and Technology (NIST). Over the past 2 years, the team has made substantial advances in quantum channel measurement and performance. It has also taken the initial steps toward establishing a testbed for experimentation with optical networking of superconducting quantum nodes together with transduction devices. Having a single infrastructure where various devices and optical channels can be connected and measured in concert will allow both direct comparisons of devices under controlled conditions and enable measurement of more realistic topologies involving repeaters, transducers, and optical channels.

The 5G/6G core network work started in 2021 as part of the Advanced Network Technologies division in the Information Technology Laboratory and was transferred to CTL in the same year. The technical objectives of this program are to advance networking and measurement sciences and promote standards for 6G networks, focusing on core network and end-to-end network services. The current technical focus areas are artificial intelligence (AI), native architectures for 6G core networks, selected foundational technologies (end-to-end service quality assurance, edge AI, automation for network security and resilience, and metrology), and building a testbed.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

The trustworthy networks group has two areas of focus: improvements in the robustness and security of Internet protocols (IPs) and initial investigations into a disruptive networking technology—information-centric networking—which has the potential to be the basis for applications that would be difficult to develop using the existing IP suite and could someday replace Transmission Control Protocol (TCP)/IP as the global protocol stack of the Internet.

Area-Wide Challenges and Opportunities

The Quantum Networking program spans a number of groups across NIST, while the quantum channel, quantum transducer, and quantum networking projects were made part of CTL when CTL was reorganized. The participants in this arena have a long track record of productive collaboration that has produced many successes, including some substantial breakthroughs and improvements in the state of the art.

Key Recommendation 1: NIST should ensure there is adequate coordination of work across the multiple laboratories engaged in quantum networking efforts to make sure that synergies and efficiencies are realized and different laboratories do not work at cross purposes, especially across the various NIST laboratories involved in quantum computing and metrology research.

Two notable technical areas in which CTL has shown consistent leadership are the specifications for Border Gateway Protocol (BGP) Route Origin Authorization and its supporting Resource Public Key Infrastructure. BGP is a dynamic routing protocol that automatically learns routes between sites that are connected by using site-to-site VPN connections. This reduces the need for manual route configuration on routers. (Microsoft 2021) This work on BGP is expected to continue for the foreseeable future, as ossification of the IPs and infrastructure makes substantial incremental improvement difficult. One recent potential area of opportunity is the possible adoption of BGPSec (BGP security) in addition to BGP origin authentication. In the past, BGPSec was considered infeasible on core Internet routers due to the heavy computational load, but recent large improvements in the computational capabilities of modern routers allow the community to reassess this.

Recommendation 3-1: CTL should extend the existing NIST-developed metrology to assess the operation and effectiveness of Route Origin Authorization to be able to measure performance and assess the feasibility of BGPSec (BGP security) deployment.

ASSESSMENT OF TECHNICAL PROGRAMS

Accomplishments

Quantum Network Architecture, Protocols, and Metrology

NIST continues to hold a leadership role in the field of quantum channel metrology. A few results are particularly important and worth calling out:

  • A world-record for quantum channel efficiency (at 41 percent),
  • The achievement of practical remote entanglement, and
  • Substantial progress in the creation of practical transducers for the conversion between the radio frequency and optical domains.
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

5G/6G Core Networks

Because the 5G/6G core network program is new, the focus has been on research, in collaboration with academia and industry, to develop selected networking and measurement technologies to establish the technical foundation that will enable the team to contribute to 6G standardization. It is believed that these will lay the foundation to shift to a user-centric architecture required in 6G. There is not much collaboration with the Next Generation Wireless group currently, but this will be developed in the coming months and years. There are essentially two projects, the Edge AI and Edge Learning Project, and the End-to-End Service Quality Assurance Project.

The goal is to develop edge-enabled learning architectures using machine learning (ML) and algorithms that can address edge-learning challenges. The key challenges are that access nodes and core networks manage their data independently. Establishing some cross-domain work between access nodes and core networks is essential for this project. These are areas that are being explored:

  • Resource constraints,
  • Non-independent and identically distributed data,
  • Data privacy, and
  • Security vulnerabilities.

The goal of this project is to develop architectures and algorithms for autonomously managed subsystems to collectively ensure end-to-end service quality. As a result, the researchers have developed a new distributed architecture and algorithm that can enable access nodes and core networks to autonomously “cooperate” with each other to dynamically negotiate their local quality of service budgets and to collectively meet end-to-end quality of service goals by sharing only their estimates of the global constraint functions, without disclosing their local decision variables. They demonstrate that this new distributed algorithm converges to an optimal solution with high probability, and present numerical results to demonstrate that the convergence occurs quickly, even with measurement noise.

The next step will be to limit the amount of information needed to achieve maximal accuracy and rapid convergence without increasing the risk that the algorithm converges too slowly, or converges to a local minimum. This would address the resource constraint, data privacy, and security vulnerabilities objectives listed above.

The goals of the two projects described above aim to advance algorithms for autonomously managed systems, including vehicles, which is relevant to vehicle teleoperation. NIST convened a vehicle teleoperation forum that brought together industry, academic, and government stakeholders to discuss the state of the art, challenges, opportunities, and future directions for research. Examples of thee include performance and safety measurements under resource constraints, and architectural elements that ensure data security and privacy. An industry consortium was created, the Teleoperation Consortium, and NIST is serving on its advisory board. The consortium enables collaboration between the companies, organizations, and governmental bodies engaged in developing bidirectional vehicle communications and standardization needs.

Trustworthy Networks

IP security is a long-standing program (15+ years) with an impressive track record and high ongoing relevance to the broad networking community. The various CTL projects on BGP security continue to hold a leadership role in the networking community. The work on Domain Name System (DNS) security, while somewhat plateauing, continues to be valuable. Notable activities on network protocol security include

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
  • Co-authorship and technical input to BGP protocol security standards;
  • Rapid prototyping of proposed standards specifications;
  • Measurement and monitoring tools for assessing BGP security, detecting breaches in a timely fashion, and performing forensics after disruptive events; and
  • Publication of deployment and best practices guides.

Equally strong to this area has been work on DNS security, particularly the definition and deployment of DNSSEC (DNS Security Extensions) protocols. NIST has been a universally recognized international expert in DNSSEC and has been key to its widespread (albeit slow) deployment after a long gestation period. This is winding down and ought to be credited as a major success for the team. There are, however, opportunities for further engagement, particularly in the privacy arena.

Providing DNS privacy deeply affects the interests of users, DNS operators, and cloud application providers. The proposals under current standardization efforts need to reflect the give-and-take that exists among these parties and strike a good balance of their various interests.

One set of work that CTL has had, tasks associated with the Office of Management and Budget mandate to assist in transitioning government networks to IPv6, is drawing to a close, reaching planned completion in 2025. As a result, resources are being moved incrementally off this effort and will be available for other work.

More recently, the Core Network Technologies group has taken a leading role in industry and standards organizations to define both the processes and technology for the new area of Zero Trust Networking. This effort aims to shift the overall approach to securing networks and their associated applications from one where the level of trust in performing actions is undefined and arbitrary, to one in which actions are by default not allowed and explicit authorization is required for establishing the necessary trust to allow them to take place. CTL’s role has been one of

  • Defining the essential elements of a zero trust architecture,
  • Enumerating general deployment models,
  • Providing insight into use cases, and
  • Articulating a high-level roadmap for adopting Zero Trust in Enterprise settings.

These elements have been formalized through the publication of a Zero Trust Architecture document (SP 800-207) and a joint demonstration project with a number of industry partners. This work is expected to continue with revisions of the architecture document as more is learned and deployment experience gained, and further formalization of the appropriate elements through standardization in the Internet Engineering Task Force and elsewhere.

The second area of focus on disruptive networking technologies is relatively new. One strong focus of the team is in the creation, enhancement, and maintenance of the NIST high-speed Named Data Networking (NDN) forwarder, which has had a positive reception in the Information Centric Networking (ICN) research community. The high-speed NDN forwarder has been adopted by at least two high-profile research projects in large-scale scientific data—the N-DISE (Named Data Networking for Data Intensive Science Experiments) project using data from the European Organization for Nuclear Research’s (CERN’s) Large Hadron Collider, and applications to genomics data. This project is quite small (four to five staff), so it is not resourced to be a major influence on the field.

The zero trust networks group has had notable accomplishments in the publication of the Zero Trust Architecture in SP 800-207 and in orchestrating a wide variety and a large number of industry partners to come together to bring coherence to a rapidly evolving arena with a mix of technologies and strong competitive pressures.

Likewise, notable accomplishments in the area of IP Security are the clear ability to declare success for the longstanding work on DNSSEC and playing a key role in the deployment of BGP origin authentication through the Resource Public Key Infrastructure.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

CTL has had notable accomplishments in the area of ICN in which it was able to create the NIST high-speed NDN forwarder and its adoption by two high-profile research projects to host and manage the NDN community, which brings together a set of active researchers using the NDN protocol suite for research into ICN. This semi-formal organization hosts workshops for the presentation of in-progress research, the coordination of the NDN testbed network run by the University of California, Los Angeles, and other institutions outside of NIST, and provides email lists for collaboration on an ongoing basis. They also published at least one paper in metrology for ICN networks.

Challenges and Opportunities

Quantum Network Architecture, Protocols, and Metrology

As the field matures, work on actual quantum networking beyond communication over a single quantum channel will gain importance. Emerging areas of research and commercialization of quantum network technology include

  • Quantum repeater implementation and metrology,
  • Network-wide measurement techniques (going beyond measuring single channels), and
  • More complex entanglement schemes that can enable multicast, among other useful capabilities.

There are significant opportunities for NIST to provide leadership in a number of emerging areas, such as quantum repeater implementation and metrology, network-wide measurement techniques (going beyond measuring single channels), and more complex entanglement schemes. The management of quantum channels using protocols running over paired classical channels is a rapidly evolving area for which CTL expertise (in the robust networking group) for secure and performant protocol design is important to exploit.

5G/6G Core Networks

The 5G/6G core networks program has developed a state-of-the-art federated learning algorithm, an AI/ML technology, for non-independent and identically distributed data simulation with proven convergence. The next steps are algorithms that can address all four challenges: 5G and 6G networks, energy efficiencies, data management, and digital twins.

Key Recommendation 2: CTL should establish an artificial intelligence (AI)/machine learning (ML) 5-year roadmap. This roadmap should include the application of AI and ML to 5G and 6G core networks, energy efficiencies, data management, and digital twins.

CTL needs to be very selective in determining which areas to focus on because the 5G/6G core networks program is only about 1 year old and has barely started. This area is very broad and complex. CTL appears to be making progress in all areas where resources have been allocated (i.e., resource constraints, non-independent and identically distributed data, data privacy, and security vulnerabilities) and it hopes to expand the program moving forward.

CTL has recognized that building a 5G testbed would be a great research asset and it is working toward that goal. CTL wants to develop an open-source 5G testbed that could also be used in the context of beyond 5G and 6G core networks. This core network would support radio access networks and applications across NIST and various government agencies. This would hopefully be used to establish internationally federated testbeds to support global research collaboration and explore new federated networking capabilities.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

So far, the software and hardware acquisition for the testbed are in progress, but no details on the status of those acquisitions were provided. CTL has established a global collaboration team to develop federated 5G testbeds. They are leveraging the Institute of Electrical and Electronics Engineers (IEEE) 2302 Standard that the group led to developing federated 5G testbeds with a number of partners such as the Electronics and Telecommunications Research Institute, Mobigen, INSoft, Katech, Kiat-USA, the University of Arizona, and the University of Missouri-Kansas City. They had a kick-off meeting on May 16-18, 2022, at NIST.

One of the key challenges will be to secure funding and add resources to maintain the momentum gathered in the first year. Surely a case could be made that 5G/6G core networks is worthy of attracting some funding from the CHIPS and Science Act of 2022 (P.L. 117-167), but a solid 5-year roadmap needs to be in place in the near future.

Key Recommendation 3: CTL should accelerate the development of a testbed with the Next-Generation Wireless team to enable a system that can fully test 5G/6G systems. CTL should foster collaboration between the Core Networks and Next-Generation Wireless teams to find and leverage synergies.

Trustworthy Networks

In the trustworthy networks group, aside from the BGPSec possibilities noted above, more disruptive activities are in progress (mostly in Europe) on finally replacing BGP with a protocol that has much better security characteristics while enabling more flexible and higher performance path selection. NIST could take a role in helping to evaluate the potential benefits of such approaches, particularly the SCION protocol family and other protocols being considered by the Path Aware Networking Research Group (part of the Internet Research Task Force). NIST could also help determine the feasibility and the various trade-offs needed to consider such a transition.

Recommendation 3-2: CTL should increase its involvement in new routing technologies for global Internet routing through experimentation and analysis of initial deployments of SCION and other protocols under consideration by the Path Aware Networking Research Group.

As the deployment of DNSSEC has become essentially routine, the focus of DNS security has pivoted to the privacy aspects. NIST could take a more active role in developing measurement and evaluation tools for DNS privacy; help balance the interests of large cloud providers, DNS service providers, and users; and help determine which protocols (e.g., DNS over TLS, DNS over HTTP, oblivious DNS) get deployed and how the protocols are managed.

Recommendation 3-3: CTL should take a more active role in the development and dissemination of measurement and evaluation tools for DNS privacy; help to balance the interests of large cloud providers, DNS service providers, and users; and help determine which protocols (e.g., DNS over TLS, DNS over HTTP, Oblivious DNS) get deployed and how they are managed.

For Zero Trust Networks, keeping up with this rapidly evolving arena will require resources of multiple types, including architecture, tools development, and some novel metrology to both assess effectiveness and to perform forensics when failures of the various protocols, algorithms, and code are discovered. There is also some danger that the current enthusiasm goes through a “trough of disillusionment” when the inevitable limitations of the approach become more generally recognized. Zero trust networking research and metrology require resources of multiple types, as noted above. It is important to match the skill portfolio to the emerging tasks in this area.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

For ICNs, there is an opportunity to expand adoption of the NIST high-speed NDN forwarder and make it either a co-reference or a replacement reference for the now quite old and messy Network Forwarding Daemon. However, doing so will require a significant expansion of support capability, and of the tooling needed to rapidly incorporate new functionality introduced by researchers. Further along, making this forwarder the focus of an expanded NDN testbed that covers Internet scale could enhance both the adoption and rapid evolution of ICN in both the research community and industry.

The adoption of ICN beyond a small research community has been slow and does not appear to be on the verge of a breakout with significant industrial and commercial participation. Even in certain niches, like industrial control, vehicular networking, or ad hoc wireless networks, interest has been spotty. There is a non-trivial risk that interest in ICN will wane.

Given NIST’s expertise in metrology, placing more focus and resources on measurement tools, synthetic and real traffic trace generation and maintenance, and publications to provide apples-to-apples comparisons of various ICN protocols and architectures would be a major contribution to the field.

Recommendation 3-4: There is a non-trivial risk that interest in Information Centric Networking (ICN) will wane. CTL should reassess its ICN projects in 1 to 2 years to see if they still represent a good use of NIST’s limited resources.

Advanced Distributed Denial of Service Attack Mitigation Techniques

CTL was actively looking into the distributed denial of service attack mitigation techniques before its re-organization. The security of the 5G/next-generation networks needs to be measured and assessed for deployment in national laboratories and public safety research centers more than ever before, because the commoditization of 5G core allows for amplification attacks from a single Radio Access Network to infiltrate multi-vendor core networks, thereby increasing security risks.1

Recommendation 3-5: CTL should continue its distributed denial of service attack mitigation work as it applies to 5G Radio Access Network security.

PORTFOLIO OF SCIENTIFIC EXPERTISE

Accomplishments

The staff working on IPs is strong and has maintained impressive continuity over many years, while successfully integrating new personnel as needed. Through its history as part of the security focus in the Information Technology Laboratory, this group has a good reputation and can recruit top talent.

The staff on the NDN project is new and partially drawn from finishing students from universities working in this area. They have done a considerable amount of work, and, in the creation of the high-speed NDN forwarder, have accomplished quite a bit for a small group.

For the Quantum Network Architecture, Protocols, and Metrology group, the movement to CTL has not slowed progress in this emerging area, and the scientific team has been well absorbed into CTL’s overall program of work. This group has authored numerous publications at the cutting edge of quantum metrology, channel efficiency, transducers, and remote entanglement generation. The work has been picked up by various teams working in the same area, such as the groups at Keio University in Japan and Delft University in the Netherlands. As this is a rapidly evolving and growing area of research and

___________________

1 Amplification attacks allow and attacker to dramatically increase the power of an attack, yielding significant consequences from a relatively small amount of attack resources. For more information see https://www.radware.com/security/ddos-knowledge-center/ddospedia/amplification-attack.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×

eventual standardization, expanding staffing levels on these projects will enable NIST to remain a leader in quantum metrology, quantum channel design, and the architecture of quantum networks.

The 5G/6G Core Networks group has been active and influential. In only its first year of existence, this group has submitted over 20 papers and has given over 30 presentations and invited talks. In addition, they helped establish the Teleoperation Consortium.

Challenges and Opportunities

In the area of Internet protocol work with BGP, continued efforts are seeing less reward as this work has been widely adopted and is in near-universal use by Internet service providers. Hence, either moving on to new areas or finding additional challenges in privacy and security to tackle would allow CTL to continue and potentially enhance its leadership in trustworthy networks.

For the disruptive networking, and especially the ICN work, this needs to be expanded with more staff to increase progress on the forwarder work and to undertake additional metrology projects, such as the creation of synthetic traces and the tools to measure ICN networks.

Core networks is a wide area to investigate and there are numerous opportunities; one of the main challenges is to identify where to invest very limited resources. New network and service orchestration solutions exploiting AI and ML will result in significant network automation that will reduce operating costs. This is an area that CTL chose to address with their limited staff, but other areas, such as Service Base Architecture,2 which could be an enabler to a network that continuously adapts to communication conditions, could be an interesting area of focus in the future.

EFFECTIVE DISSEMINATION OF OUTPUTS

Accomplishments

Much has been achieved with a limited staff of 6-8 members with the 5G/6G Core Networks group. As mentioned previously, in only its first year of existence, this group has submitted or published over 20 significant papers and has given over 30 presentations and invited talks. In addition, they helped establish the Teleoperation Consortium.

The work on IPs protocols continues to produce a variety of extremely valuable outputs, from standards publications in the Internet Engineering Task Force, to various guides, to implementers and network operators that serve as “go-to” references for a large fraction of the Internet community. The ICN work has produced a few meaningful publications that are well regarded and were presented at the top research conference in the field (the Association for Computing Machinery’s Information-centric Networking Conference). The NIST NDN forwarder has been adopted by at least one significant research project (N-DISE) and is a critical part of that project’s needed infrastructure. In addition, NIST’s role as host/organizer of the NDN community meetings helps the NDN part of the ICN research community to have a forum for sharing ideas and intermediate results. The panel was not able to discern any challenges or opportunities in this area.

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2 “Service-Based Architectures provide a modular framework from which common applications can be deployed using components of varying sources and suppliers. The 3GPP defines a Service-Based Architecture (SBA), whereby the control plane functionality and common data repositories of a 5G network are delivered by way of a set of interconnected Network Functions (NFs), each with authorization to access each other’s services.” What is the 5G Service-Based Architecture (SBA)?, https://www.metaswitch.com/knowledge-center/reference/what-is-the-5g-service-based-architecture-sba, accessed November 7, 2022.

Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 16
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 17
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 18
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 19
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 20
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 21
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 22
Suggested Citation:"3 Core Network Technologies." National Academies of Sciences, Engineering, and Medicine. 2023. 2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory. Washington, DC: The National Academies Press. doi: 10.17226/26778.
×
Page 23
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2022 Assessment of the National Institute of Standards and Technology's Communications Technology Laboratory Get This Book
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At the request of the director of the National Institute of Standards and Technology, this report assesses the management of Standards and Technology Communications Technology Laboratory (CTL), focusing on the work, facilities, equipment, personnel, portfolios of scientific expertise, and effective dissemination of the results.

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