Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-7570-2.CH007
G. Prasad, Deepak Mishra, A. Hossain
With increase in demand of data traffic with no compromise on the underlying quality of service (QoS), the coexistence problem arises due to high electricity consumption by the network architecture which results in a huge CO2 emission and thereby causing various health hazards. Efficient utilization of the resources can reduce the cost of power consumption which will increase the economy-characteristics of the network. The resource consumption can be reduced under an intelligent technology-neutral policies which optimizes the deployment of the network architecture along with their transmit power paving the way for fifth generation (5G) in green wireless communications. On another front, the ultra-dense deployment of the small cells can increase the frequency reuse factor as well as help in reducing the energy consumption. This chapter designs the energy efficient networks while satisfying the underlying QoS by joint optimization of available resources depending on the interoperability challenges in terrestrial, underwater acoustic, and free space optical (FSO) communications.
{"title":"QoS-Aware Green Communication Strategies for Optimal Utilization of Resources in 5G Networks","authors":"G. Prasad, Deepak Mishra, A. Hossain","doi":"10.4018/978-1-5225-7570-2.CH007","DOIUrl":"https://doi.org/10.4018/978-1-5225-7570-2.CH007","url":null,"abstract":"With increase in demand of data traffic with no compromise on the underlying quality of service (QoS), the coexistence problem arises due to high electricity consumption by the network architecture which results in a huge CO2 emission and thereby causing various health hazards. Efficient utilization of the resources can reduce the cost of power consumption which will increase the economy-characteristics of the network. The resource consumption can be reduced under an intelligent technology-neutral policies which optimizes the deployment of the network architecture along with their transmit power paving the way for fifth generation (5G) in green wireless communications. On another front, the ultra-dense deployment of the small cells can increase the frequency reuse factor as well as help in reducing the energy consumption. This chapter designs the energy efficient networks while satisfying the underlying QoS by joint optimization of available resources depending on the interoperability challenges in terrestrial, underwater acoustic, and free space optical (FSO) communications.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133869808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-7998-1152-7.ch009
Tarek M. Salem
This chapter addresses cognitive radio systems (CRSs) in the 5G network and presents the existing, emerging, and potential applications employing CRS capabilities and the related enabling technologies, including the impacts of CRS technology on the use of spectrum from a technical perspective. The description of such technologies, operational elements, and their challenges are also presented. Furthermore, this chapter provides high level characteristics, operational and technical requirements related to CRS technology, their performances, and potential benefits. Finally, factors related to the introduction of CRS technologies and corresponding migration issues are discussed.
{"title":"The State of the Art in Cognitive Radio Networks in 5G Hetergeneous Networks","authors":"Tarek M. Salem","doi":"10.4018/978-1-7998-1152-7.ch009","DOIUrl":"https://doi.org/10.4018/978-1-7998-1152-7.ch009","url":null,"abstract":"This chapter addresses cognitive radio systems (CRSs) in the 5G network and presents the existing, emerging, and potential applications employing CRS capabilities and the related enabling technologies, including the impacts of CRS technology on the use of spectrum from a technical perspective. The description of such technologies, operational elements, and their challenges are also presented. Furthermore, this chapter provides high level characteristics, operational and technical requirements related to CRS technology, their performances, and potential benefits. Finally, factors related to the introduction of CRS technologies and corresponding migration issues are discussed.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129325880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-7146-9.CH006
L. Contreras
The advent of 5G introduces the concept of network slicing which is meant to permit network service providers to overcome the great challenge of forthcoming 5G services: how to support and operate different kinds of services with very distinct needs onto the same infrastructure. Deploying altogether on the same network makes it quite difficult to define a common architecture capable of keeping the diverse requirements of all of them. The network slicing concept foresees a number of logically independent slices, each comprising different network nodes and service functions, which are interconnected and are involved in the delivery and the operation of a specific service. By instantiating network slices, the network will be able to provide completely different services in a dynamic way over the same infrastructure. This chapter overviews the challenges raised by the implementation of the network slicing concept and which will be faced by the network operators.
{"title":"Slicing Challenges for Operators","authors":"L. Contreras","doi":"10.4018/978-1-5225-7146-9.CH006","DOIUrl":"https://doi.org/10.4018/978-1-5225-7146-9.CH006","url":null,"abstract":"The advent of 5G introduces the concept of network slicing which is meant to permit network service providers to overcome the great challenge of forthcoming 5G services: how to support and operate different kinds of services with very distinct needs onto the same infrastructure. Deploying altogether on the same network makes it quite difficult to define a common architecture capable of keeping the diverse requirements of all of them. The network slicing concept foresees a number of logically independent slices, each comprising different network nodes and service functions, which are interconnected and are involved in the delivery and the operation of a specific service. By instantiating network slices, the network will be able to provide completely different services in a dynamic way over the same infrastructure. This chapter overviews the challenges raised by the implementation of the network slicing concept and which will be faced by the network operators.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125635538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-7998-1253-1.ch009
B. Muneer, F. Shaikh, Qi Zhu, Zuqing Zhu
Under the umbrella of 5G there are many technology projects (e.g., internet of things, in-vehicle communication, smart cities, e-health systems, etc.). To understand the concept of IoT, the authors first understand the revolution of technological networks and later discuss what IoT is, the importance of antennas, and future vision.
{"title":"Antennas for IoT Application","authors":"B. Muneer, F. Shaikh, Qi Zhu, Zuqing Zhu","doi":"10.4018/978-1-7998-1253-1.ch009","DOIUrl":"https://doi.org/10.4018/978-1-7998-1253-1.ch009","url":null,"abstract":"Under the umbrella of 5G there are many technology projects (e.g., internet of things, in-vehicle communication, smart cities, e-health systems, etc.). To understand the concept of IoT, the authors first understand the revolution of technological networks and later discuss what IoT is, the importance of antennas, and future vision.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123111073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-7998-1152-7.ch012
Mohammed A. Salem, S. El-kader, M. Youssef, I. Tarrad
Machine type communication (MTC), additionally called machine-to-machine (M2M) communications, broadly is referring to a number of cooperating machines exchange sensed data or information and make decisions with slight or zero human intervention. M2M technology will let a massive number of devices to be interconnected over the internet leading to a rapid development in recent time, which can be a promising enabling key for many areas, particularly for the internet of things (IoT) and 5th generation (5G) networks. This chapter presents a summary and state of art of M2M communications characteristics, taxonomy, applications, different technologies for deploying of M2M communications, and future challenges.
{"title":"M2M in 5G Communication Networks","authors":"Mohammed A. Salem, S. El-kader, M. Youssef, I. Tarrad","doi":"10.4018/978-1-7998-1152-7.ch012","DOIUrl":"https://doi.org/10.4018/978-1-7998-1152-7.ch012","url":null,"abstract":"Machine type communication (MTC), additionally called machine-to-machine (M2M) communications, broadly is referring to a number of cooperating machines exchange sensed data or information and make decisions with slight or zero human intervention. M2M technology will let a massive number of devices to be interconnected over the internet leading to a rapid development in recent time, which can be a promising enabling key for many areas, particularly for the internet of things (IoT) and 5th generation (5G) networks. This chapter presents a summary and state of art of M2M communications characteristics, taxonomy, applications, different technologies for deploying of M2M communications, and future challenges.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"10 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132468657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-7998-1152-7.ch011
Shimaa Abdelnaby AbdelHakeem, Anar A. Hady, Hyungwon Kim
Recently, the automotive industries have accelerated the deployment of Cellular V2X as a motivation to integrate vehicular communication with NewRadio-5G (NR-5G) technology. Nowadays, two critical technologies are concurrently supporting V2X communication: IEEE802.11p and cellular technologies. C-V2X is standardized and designed by the Third Generation Partnership Project (3GPP) for automotive services. C-V2X supports two communication modes through a single platform to provide Wifi-short-range and cellular-long-range communication. Wifi-short-range communication doesn't require network subscription or coverage while the cellular-long-range requires network subscription and coverage. LTE-V2X is the current standard of C-V2X which completed in March-2017 as the 3GPP-Release 14 and enhanced to support the upcoming 3GPP-Release 16 which support the NR-5G capabilities, enhancement, and services. In this chapter, the authors propose the Optimizing of 5G with V2X and analyzing the current V2X standards, introducing the evolution of 5G, challenges, features, requirements, design, and technologies.
{"title":"Optimizing 5G in V2X Communications","authors":"Shimaa Abdelnaby AbdelHakeem, Anar A. Hady, Hyungwon Kim","doi":"10.4018/978-1-7998-1152-7.ch011","DOIUrl":"https://doi.org/10.4018/978-1-7998-1152-7.ch011","url":null,"abstract":"Recently, the automotive industries have accelerated the deployment of Cellular V2X as a motivation to integrate vehicular communication with NewRadio-5G (NR-5G) technology. Nowadays, two critical technologies are concurrently supporting V2X communication: IEEE802.11p and cellular technologies. C-V2X is standardized and designed by the Third Generation Partnership Project (3GPP) for automotive services. C-V2X supports two communication modes through a single platform to provide Wifi-short-range and cellular-long-range communication. Wifi-short-range communication doesn't require network subscription or coverage while the cellular-long-range requires network subscription and coverage. LTE-V2X is the current standard of C-V2X which completed in March-2017 as the 3GPP-Release 14 and enhanced to support the upcoming 3GPP-Release 16 which support the NR-5G capabilities, enhancement, and services. In this chapter, the authors propose the Optimizing of 5G with V2X and analyzing the current V2X standards, introducing the evolution of 5G, challenges, features, requirements, design, and technologies.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115515329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-6023-4.CH006
Elisavet Grigoriou
In the past few years, it's observed that cellular operators have experienced a fast growth of mobile broadband subscribers and traffic volume per subscriber. Simultaneously, operators are moving from a single to a multi-service offering by adding new services. This chapter presents a survey of the Quality of Service (QoS) drivers in LTE and LTE-Advanced, focusing on IP Frameworks and IP Services. It also includes a detailed list and description of the resource management mechanisms, such as power saving, admission control, scheduling and resource allocation that play a vital role in QoS. The authors describe the State-of-the-Art in IP frameworks and Services such as video, VoIP, Video on Demand (VoD). Also, resource management mechanisms are described such as Energy efficiency, admission control, and scheduling. In the end, the authors mentioned the future directions about QoS in 5G networks.
{"title":"A Survey of Quality of Service in Long Term Evolution (LTE) Networks","authors":"Elisavet Grigoriou","doi":"10.4018/978-1-5225-6023-4.CH006","DOIUrl":"https://doi.org/10.4018/978-1-5225-6023-4.CH006","url":null,"abstract":"In the past few years, it's observed that cellular operators have experienced a fast growth of mobile broadband subscribers and traffic volume per subscriber. Simultaneously, operators are moving from a single to a multi-service offering by adding new services. This chapter presents a survey of the Quality of Service (QoS) drivers in LTE and LTE-Advanced, focusing on IP Frameworks and IP Services. It also includes a detailed list and description of the resource management mechanisms, such as power saving, admission control, scheduling and resource allocation that play a vital role in QoS. The authors describe the State-of-the-Art in IP frameworks and Services such as video, VoIP, Video on Demand (VoD). Also, resource management mechanisms are described such as Energy efficiency, admission control, and scheduling. In the end, the authors mentioned the future directions about QoS in 5G networks.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121091592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-9199-3.CH005
S. Routray
Internet of things (IoT) is an integral part of modern digital ecosystem. It is available in different forms. Narrowband IoT (NBIoT) is one of the special forms of the IoTs available for deployment. It is popular due to its low power wide area (LPWA) characteristics. For new initiatives such as smart grids and smart cities, a large number of sensors will be deployed and the demand for power is expected to be high for such IoT deployments. NBIoT has the potential to reduce the power and bandwidth required for large IoT projects. In this chapter, different practical aspects of NBIoT deployment have been addressed. The LPWA features of NBIoT can be realized effectively if and only if its deployment is done properly. Due to its large demand, it has been standardized in a very short span of time. However, the 5G deployment of NBIoT will have some new provisions.
{"title":"Deployment of Narrowband Internet of Things","authors":"S. Routray","doi":"10.4018/978-1-5225-9199-3.CH005","DOIUrl":"https://doi.org/10.4018/978-1-5225-9199-3.CH005","url":null,"abstract":"Internet of things (IoT) is an integral part of modern digital ecosystem. It is available in different forms. Narrowband IoT (NBIoT) is one of the special forms of the IoTs available for deployment. It is popular due to its low power wide area (LPWA) characteristics. For new initiatives such as smart grids and smart cities, a large number of sensors will be deployed and the demand for power is expected to be high for such IoT deployments. NBIoT has the potential to reduce the power and bandwidth required for large IoT projects. In this chapter, different practical aspects of NBIoT deployment have been addressed. The LPWA features of NBIoT can be realized effectively if and only if its deployment is done properly. Due to its large demand, it has been standardized in a very short span of time. However, the 5G deployment of NBIoT will have some new provisions.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128754583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-1712-2.CH009
Shaoyi Xu, Tianhang Fu
The high-speed railway (HSR) is a typical application case in 5G systems. Mobile relay stations (MRSs) which are mounted in a high-speed train (HST) is popular system architecture for high-speed mobile communications. However, sharing spectrums between the macro cell and the MRS cell, interference exists in this hybrid system. In this chapter, we investigate the downlink of a multi-cellular decode and forward (DF) relayed orthogonal frequency division multiple access (OFDMA) system and formulate the problem to maximize the system sum rate of all cells subject to a total power constraint and a new proposed time delay constraint. An effective resource allocation scheme combined by greedy sub-carriers allocation and geometric programming (GP) based power allocation algorithm is proposed to optimize subcarrier allocation and power allocation. Numerical experiments verify that the proposed resource allocation scheme outperforms the other traditional approaches and the necessity of introducing the time delay constraint.
{"title":"Geometric Programming Based Resource Allocation for 5G High-Speed Mobile Networks","authors":"Shaoyi Xu, Tianhang Fu","doi":"10.4018/978-1-5225-1712-2.CH009","DOIUrl":"https://doi.org/10.4018/978-1-5225-1712-2.CH009","url":null,"abstract":"The high-speed railway (HSR) is a typical application case in 5G systems. Mobile relay stations (MRSs) which are mounted in a high-speed train (HST) is popular system architecture for high-speed mobile communications. However, sharing spectrums between the macro cell and the MRS cell, interference exists in this hybrid system. In this chapter, we investigate the downlink of a multi-cellular decode and forward (DF) relayed orthogonal frequency division multiple access (OFDMA) system and formulate the problem to maximize the system sum rate of all cells subject to a total power constraint and a new proposed time delay constraint. An effective resource allocation scheme combined by greedy sub-carriers allocation and geometric programming (GP) based power allocation algorithm is proposed to optimize subcarrier allocation and power allocation. Numerical experiments verify that the proposed resource allocation scheme outperforms the other traditional approaches and the necessity of introducing the time delay constraint.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114848119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.4018/978-1-5225-6023-4.CH001
Stojan Kitanov, B. Popovski, T. Janevski
Because of the increased computing and intelligent networking demands in 5G network, cloud computing alone encounters too many limitations, such as requirements for reduced latency, high mobility, high scalability, and real-time execution. A new paradigm called fog computing has emerged to resolve these issues. Fog computing distributes computing, data processing, and networking services to the edge of the network, closer to end users. Fog applied in 5G significantly improves network performance in terms of spectral and energy efficiency, enable direct device-to-device wireless communications, and support the growing trend of network function virtualization and separation of network control intelligence from radio network hardware. This chapter evaluates the quality of cloud and fog computing services in 5G network, and proposes five algorithms for an optimal selection of 5G RAN according to the service requirements. The results demonstrate that fog computing is a suitable technology solution for 5G networks.
{"title":"Quality Evaluation of Cloud and Fog Computing Services in 5G Networks","authors":"Stojan Kitanov, B. Popovski, T. Janevski","doi":"10.4018/978-1-5225-6023-4.CH001","DOIUrl":"https://doi.org/10.4018/978-1-5225-6023-4.CH001","url":null,"abstract":"Because of the increased computing and intelligent networking demands in 5G network, cloud computing alone encounters too many limitations, such as requirements for reduced latency, high mobility, high scalability, and real-time execution. A new paradigm called fog computing has emerged to resolve these issues. Fog computing distributes computing, data processing, and networking services to the edge of the network, closer to end users. Fog applied in 5G significantly improves network performance in terms of spectral and energy efficiency, enable direct device-to-device wireless communications, and support the growing trend of network function virtualization and separation of network control intelligence from radio network hardware. This chapter evaluates the quality of cloud and fog computing services in 5G network, and proposes five algorithms for an optimal selection of 5G RAN according to the service requirements. The results demonstrate that fog computing is a suitable technology solution for 5G networks.","PeriodicalId":298363,"journal":{"name":"Research Anthology on Developing and Optimizing 5G Networks and the Impact on Society","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116465583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：