International Conference on Communication and Signal Processing, April 2-4, 2015, India
4G Protocol and Architecture for BYOD Over Cloud Computing Aparna Bhat, Vishwanath Gojanur, Rajeshwari Hegde, Member, IEEE Abstract—The Fourth Generation communication systems have speeds higher than those of 3G and have a more complicated architecture dedicated and defined for handling such voluminous data and to accommodate more users. The architecture also employs a specified protocol stack, software defined network along with their own security issues for wireless applications and remote access. In this paper we are trying to present the protocol stack for the 4G architecture and network, with particular applications directed towards BYOD and Cloud Computing (Virtual Networking). Index Terms—4G, E-UTRAN, BYOD (Bring Your Own Device), UMTS, 3GPP (3rd Generation Plus Plus), MDM (Mobile Device Management), LTE (Long Term Evolution), Femto Cell.
I. INTRODUCTION The fourth generation of communications systems network is envisaged to encompass a multitude of cellular and wireless networking technologies and protocols which include WPAN, WLAN evolved over time from UMTS, LTE Advanced EUTRAN and 3GPP. These wireless networking technologies are seamlessly interconnected by the Internet Protocol (IPV6) as a backbone network. In essence, 4G aims to transform communication architectures from traditional vertical stove piped to horizontal integrated systems. The previous technologies have served effectively for voice and data traffic, but as the network and speed demands have moved from 915Mbps (3G) to 100-500 Mbps (4G) along with new emerging corporate networking methodologies such as BYOD (Bring Your Own Device) and Cloud Computing (Database/ Software/ Platform/ Infrastructure as a Service). Hence a need for flexible, secure robust business operating models, with novel and dynamic internet-like services, with capabilities beyond the existing communication systems viz., 3GPP, LTE and UMTS. The 4G systems brings with it various limitations to fulfill requirements imposed by current mobile users,
Aparna Bhat is with Bitla Software Pvt. Ltd., Bangalore 560095, INDIA (
[email protected]). Vishwanath Gojanur is with Dept. of Telecommunication, BNMIT, Bangalore 560070, INDIA (
[email protected]). Dr. Rajeshwari Hegde is an Associate Professor with Dept. of Telecommunication, BMS College of Engineering, Bangalore 560019, INDIA (
[email protected]).
ISBN 978-1-4799-8080-2
especially with the ―anytime, anywhere with anybody‖ mode of communication, among these requirements we can mention: Software defined network, service and interface personalization, access control configuration, QoS, mobility, security and platform interoperability. A. Need for 4G
1) According to research conducted by a popular network solutions provider it concludes that in the year 2013 3G wireless (mobile) consumption grew by 146% (than in 2012) which constitutes of 43% of total network traffic. This service is catered over GPRS (2G), 2.5G and 3G service providers. 2) There are multiple standards for 3G making it hard for travelling users with interoperating cross networks, hence the need for global mobility and service-portability. 3)3G is based on primarily a WLAN concept. We need hybrid networks that utilize both wireless LAN (hot spot) concept and femto-cell or base-station wide area network design with specific protocol. 4) Researchers have come up with spectrally more efficient modulation schemes that cannot be retrofitted into other than 3G and previous generation infrastructure. 5) We need all digital packet networks that utilize IP in its fullest form with converged voice and data capability [2]. II. EVOLUTION TILL 4G 2.5G: - 2.5G wireless technology proved to be a stepping stone that bridged 2G to 3G wireless technology, and is sometimes used to describe the evolved technologies that were considered as being in 2G. While 2G and 3G have been officially defined as wireless standards by the International Telecommunication Union (ITU), 2.5G has not been defined and was created only for the purposes of marketing. 3G:-3G is the third generation of wireless technologies. This comes with enhancements over previous wireless technologies, as high-speed transmission, advanced multimedia access and 3G is mostly used with mobile phones and handsets as a means to connect the phone to the Internet or other IP networks in order to make voice and video calls, packet data. 3G is the successor of 2G and 2.5G standards. The 3G networks handle the majority of all data transfers for cellular service providers. 3.5G:-Similar to the 2.5G acronym, the reference to 3.5G is not an officially recognized standard by the ITU. It is an interim or evolutionary step to the next generation of cellular
Adhiparasakthi Engineering College, Melmaruvathur 308
technology that will be known as IMT-Advanced according to definitions by the ITU. IMT-Advanced will comprise the fourth generation of m technology. The acronym 3.5G is also known as ‗beyond 3G‘/ ‗3GPP‘. The technologies along with 3.5G are UMTS-2000, LTE and 3GPP. These 3.5G technologies are often called pre-4G as well. III. 4G ARCHITECTURE In this section, the architecture of 4G is explained in detail.
effective coverage area, also provide reliable wireless coverage. The user device can initiate handoff between cells and the device itself initiates most of additional complex actions without requiring network notification or employing inter-working functions. Each network can deploy a database of user location, device capabilities, network conditions and user preferences. In overlay network, a user accesses an overlay network consisting of several universal access points. These UAPs in turn select wireless network based on QoS and user preferences. A UAP performs protocol and frequency translation content adaptation and QoS negotiation on behalf of users. The overlay network performs handoff during roaming among UAPs. Common access protocol becomes viable if wireless network can support multi-standard access protocols. One possible situation which will require inter working between different network which uses wireless asynchronous transfer mode for wireless ATM, every wireless network must allow transmission of ATM cells with additional header or cells requiring changes in the wireless network.[8]. IV. LTE ADVANCED E-UTRAN OVERVIEW AND ARCHITECTURE 3GPP has EPS architecture with basis services as below. The two major work items are LTE and SAE, leading to EPC,EUTRAN and E-UTRA. Each has a core network, radio access network, and air interface entirely. EPS provides IP connectivity between a User Equipment and an external packet data network through E-UTRAN. The Figure 1 shows EPS, Circuit Switched elements and 3GPP RANs and services network have PCRF and HSS.
Fig.1. 4G Architecture
There is there possible architecture of 4G; multimode device overlay network and common access protocol. Multimode devices architecture uses a single physical terminal with multiple interfaces to access services on different wireless networks. It may improve call completion and expand
Fig. 2. LTE-Advanced E-UTRAN protocol stack
In this section we give an overview of the E-UTRAN architecture and functionalities defined for the LTEAdvanced systems and the main EPC node functions. The
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Figure 2 has architecture of E-UTRAN for LTE-Advanced. Core part for E-UTRAN is enhanced Node B (eNB), for air interface between user plane and control plane protocol terminations towards the UE. Every single eNBs acts as logical component that serving multiple E-UTRAN cells, having an interface interconnecting multi eNBs is called the X2 interface. Additionally, Home-eNBs (HeNBs / femtocells), or lower cost eNBS for indoor communication, could be connected to EPC directly or through a gateway to provides extended support for a multiple HeNBs. 3GPP uses relay nodes hi-end-relay-strategies to improve network performance. Hence achieving increased coverage, high data rates, improved QoS performance. Also eNBs allow EUTRAN with user and control plane termination protocols. The Protocol Stack consists of User Plane having Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC), Medium Access Control (MAC) and Physical Layer (PHY) protocols and the Control plane has the Radio Resource Control (RRC) protocols.
communicating between each other. S1-MME represents the S1 control plane interfacing between MME and eNodeB. Similarly, the transport network layer and user plane is based on IP transport and in case of reliable transport to the signaling messages; the Stream Control Transmission Protocol (SCTP) is applied over IP top. These protocol functions analogously to TCP confirming reliable, in sequence transmission of all messages with congestion control. SCTP drives analogously to Transmission Control Protocol (TCP) certifying reliable and offer in-sequence transport of messages with congestion control. The application layer signaling protocols are mentioned to S1 application protocol (S1-AP) and X2 application protocol (X2-AP) for S1 and X2 interface control planes respectively. LTE, 3GPP is also defining IP-based, flat network architecture. This architecture is defined as part of the (SAE) effort. The LTE/SAE architecture and concepts have been designed for efficient support of mass-market usage of any IP based service.
A. User Plane Protocol and Control Plane Protocol Stack The stack of user plane protocol contains the Radio Link Control (RLC) and the Packet Data Convergence Protocol (PDCP) layers usually concluded in RNC on the network side are now concluded in eNodeB. The control plane protocol stack consists of Radio Resource Control (RRC) functional conventionally applied in RNC is integrated in to eNodeB. The layers of Medium Access Control (MAC) and Radio Link Control (RLC) are implementing similar roles to user plane.
C. Evolved Packet Core overview: The EPC is IP-based core network that can be accessed through 3GPP radio access (UMTS, HSPA, HSPA, LTE) and non-3GPP radio access, allowing handover procedures within and between both access types. The access flexibility to the EPC is attractive for an operator; it allows them to have a single core for supported different services. The EPC has following components. • Mobility Management Entity (MME) This is a key control plane element. Among other functions, it is in charge of managing security functions (authentication, authorization, NAS signaling), handling idle state mobility, roaming, and hand over‘s. Also selecting the Serving Gateway (S-GW) and Packet Data Net-work Gateway (PDNGW) nodes is part of its tasks. TheS1-MME interface connects the EPC with the eNBs.
B. S1and X2 Interface Protocol Stacks The interface protocol stacks S1 and X2 are present where the protocols that used are similar in the two interfaces. The interface between S-GW and eNodeB are interconnected by S1user plane interface (S1-U).The RRC functions are include paging, system information broadcast, radio bearer control, connection management for RRC, measurement reporting to UE, and mobility functions. In the MME network side, the Non-Access Stratum (NAS) protocol is terminated while on the terminal side, the UE executes functions such as Evolved Packet System (EPS), authentication, security control, and bearer management. This interfacing is used GPRS Tunneling Protocol-User Data Tunneling (GTP-U) over UDP/IP transport. Also it is provide a nonguaranteed delivery to the user plane PDUs between S-GW and eNodeB. GTP-U is a comparatively simple IP and is based on tunneling protocol that allows a lot of tunnels between end points sets. In detail, the S1 interfacing is separating the EPC and the EUTRAN. It is splitting in to two interfaces; the first is S1-U that is transfers traffic data among S-GW and the eNodeB, and the second is S1-MMEthat is a signaling the interface between the MME and eNodeB. In other hand, the X2 is the interfacing between the eNodeBs and also involving two interfaces; the first is X2-C which is the control plane interface between eNodeBs, and X2-U is the user plane interface between eNodeBs. It is supposed that always there is an X2 interface between eNodeBs which is to provide
• Serving Gateway (S-GW) The EPC terminates at this node, and it is connected to the EUTRAN via the S1-U interface. Each UE is associated to a unique S-GW, which will be hosting several functions. It is the mobility anchor point for both local inter-eNB handover and inter-3GPP mobility, and it performs inter-operator charging as well as packet routing and forwarding. • Packet Data Network Gateway (PDN-GW) This node provides the UE with access to a Packet Data Network (PDN) by assigning an IP address from the PDN to the UE, among other functions. Additionally, the evolved Packet Data Gateway (ePDG) provides security connection between UEs connected from an un-trusted non-3GPP access network with the EPC by using IPSec tunnels. From a userplane perspective there are only the eNBs and the gateways, which is why the system is considered ‗‗flat‘‘. This results in a reduced complexity compared to previous architectures. D. Software-Defined Networking (SDN) With the rise of virtualization and cloud computing the advent of Software-Defined Networking (below, Figure 3) has
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taken center-stage. SDN, SDDC, Network Virtualization, Network Function Virtualization (NFV) are the bandwidth demanding emerging/trending technologies.
directly to modify directions in the switches, as basically there should be only one SDN controller as an OpenFlow client. In order to coordinate with the controller, security products should avail existing Interfaces in either the controller or associated orchestration frameworks to coordinate with other network services and with the core network flow itself. A different aspect of SDN is network overlays (and underlay). e.g., VXLAN enables Layer 2 subnets to be tunneled across Layer 3 networks and WAN/Internet, again creating logical network abstractions on top of the physical network. LTE wireless protocol software addresses LTE Femtocells (Home eNodeB) and pico / macro eNodeBs as well as the Evolved Packet Core (EPC) Mobility Management Entity (MME), Serving Gateway (SWG), Evolved Packet Data Gateway etc. These standards-based LTE wireless protocols allow customers to rapidly develop LTE infrastructure. V. BENEFITS OF BYOD WITH CLOUD COMPUTING
Fig.3 . Software Defined Network Layers
Network Virtualization: Server virtualization or more specifically the x86-virtualization consists of a physical hardware, x86 CPU, chipset, RAM, from the OS and applications with a hypervisor layer, translated to virtualized equivalents – vCPU, vRAM, etc. Server virtualization served to enhance workload into a VM container. This results in yielding the savings by hardware alliance. This leads to virtual switches as logical mechanism for the multiple vNIC‘s to share a physical network interface card. The network hardware onboard an x86 server is the NIC or Ethernet adapter and not a switch. Virtual networking could provide other network benefits other than allied hardware, bandwidth resource pooling, redundancy, NIC redundancy etc. The virtual network was still dependent on the physical network. Network virtualization enables the virtual network which is centered in the physical network (switches and routers). Meaning to say, just as x86 servers, network ports are abstracted into virtual ports, which can then be combined logically into virtual switches across the entire network. Two key topic areas in network virtualization: OpenFlow and overlay networks. OpenFlow - Abstracting control and data planes In the OpenFlow model, the logical abstraction in the control plane physically from the actual switches. OpenFlow is a communication standard, and formally highlights the separation – by defining a vendor-agnostic client-server API between ―smart‖ SDN controllers that would define and dictate flow control to arrays of ―dumb‖ physical switches/ports. OpenFlow has been embraced by who‘s who of networking. However, not all vendors intend to drive all value through open standards. Flow control such could be one means to integrate security appliances such as network monitoring or inline firewall appliances into the logical network. Security products should not be using calling the OpenFlow protocol
The BYOD solution is specifically designed to help the users unleash the full potential of the mobility, without compromising the integrity of the existing IT infrastructure. The BYOD phenomenon introduces a variety of network engineering and management challenges: The tools for bringing new devices and users onto the network for the first time which enables the users to get online quickly with minimum IT intervention. To ensure high service quality and availability, the IT planners need to ensure the wireless LAN (WLAN) infrastructure that can support growing numbers of mobile devices and bandwidth-hungry, delay-sensitive applications, while delivering predictable connectivity and service levels, and high quality of experience (QoE). To maintain security and mitigate risk, the IT-Planners need to put stringent authentication and authorization controls and security solutions in place to protect the IT systems, prevent data leakage, safeguard privacy, and ensure compliance. To Support diverse users and devices, the need to maintain visibility and control over an ever-changing array of company issued and personal devices—desktops, laptops, smart phones, tablets, e-readers—running various operating systems and revision levels is a crucial aspect [17]. BYOD and cloud computing are changing the way technology has been used in the workplace. More than 60% of businesses currently use a BYOD model, and forecasters suggest that number will rise to 90 percent at the end of 2014. Many American companies use public or private cloud computing systems. The combination of BYOD and Cloud Computing innovations can offer real benefits in future [16]. VI. 4G AND BYOD Mobile Device Management: this tool will help to control the devices that are supported by APIs of smartphones. This tool allows organization to lock down devices, enforce policies on the device encrypt the data or even wipe the data
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on the device locally or remotely. This tool uses security settings to monitor, control and protect the device. This is achieved by enforcing security settings, managing passwords, and installing of digital certificates for authentication. Applications can be installed, monitored, and even uninstall the same. User groups are created to share common files. This is a single point for device management irrespective of platform of operating system. Downloads can be controlled and monitored. Data backup and restoration also administered. Air configuration by devices is done remotely and can be connected to the network. The new formula: EMM = MDM + MAM + MIM + TEM Enterprise Mobile Management = Mobile Device Management + Mobile Application Management + Mobile Information Management + Telecom Expenses Management.
Fig.4. MDM Architecture
While directly accessing the web, devices can become infected by malware exploiting vulnerabilities, looking to exploit securities holes in other systems or business-related containers on the private device (Such as BYOD in a Corporate Network). There are solutions in place that protect corporate applications, database and security. It is likely that the attempted attacks will generate traffic resulting in loading-effects/ DDoS on the network and use significant system resources of the device itself. This adversely affects the end-user productivity. Such attacks can be reduced by having anti-virus / anti-malware software installed on the device. By using a MDM solution, all necessary security software, virtualization client, it can be provisioned, monitored and regularly updated over the air for the end user. MDM is used to enforce device passwords, application black or white listing, jail-breaking and rooting detection and remote wiping of all critical contents in the event of devicetheft or loss. MDM helps Corporate / Organizations to efficiently manage mobile devices on a level which is needed to meet regulatory compliance. This is MAM and MIM. By the separation of business-related content from private content on the device, business content can be secured and controlled without having to interact/interfere with private content. To segregate business emails and attachments as
restricted from being emailed via personal email accounts.MAM and MIM include automated enforcement of usage policies based on factors such as device type, type of network and user. A selective lock and wipe is also performed without impacting the user‘s personal data. Enforcing a password for the container could - from a company perspective - even make the device password superfluous. Together with TEM used for managing connectivity, data volumes and time in order to optimize communication costs, MDM, MAM and MIM are important building blocks of a comprehensive EMM solution which today‘s modern enterprises need to implement under the BYOD which has its special importance in 4G networks(and beyond).Encrypted channel is used for corporate networks. MDM (shown in Figure 4)is placed at DMZ (De-Militarized Zone), incoming traffic is enrolled and configured my MDM. authorization is by exchanging of certificates, from organizations certificate server. with help of access server the access authorizations are performed. The Sync server is for syncing and to store backups between sync server and devices.all the above communication is secured over SSL/TLS to provide an encrypted channel. MDM Device management considerations: 1) Device management: application, software, inventory, licenses, configuration, remote data wiping and locking, session management and logging. 2) Security management: data security, and applications, integration of various available patches. 3) File synchronization: continuous backup storage, session sync for FTP, and document management. Other Applications of 4G includes:B) Tele-Medicine: 4G will support remote health monitoring of patients. A user need not go to the hospital instead a user can get videoconference assistance for a doctor at anytime and anywhere. C) Tele-Geo processing applications: This is a combination of GIS (Geographical Information System) and GPS (Global Positioning System) in which a user can get the location by querying. D) Crisis management: Natural disasters can cause breakdown in communication systems. In today‘s world it might take days or weeks to restore the system. But in 4G it is expected to restore such crisis issues in a few hours. e) Education: For people who are interested in lifelong education, 4G provides a good opportunity. People anywhere in the world can continue their education through online in a cost effective manner [14]. 5G the fifth generation of mobile communication technology or 5G is in a developmental stage. Important characteristic of the new technology will be the ability of mobile devices to simultaneously send and receive information from cell towers, that things are not possible with older networks. There is no defined standard for 5G download speeds till date of publication [6].
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VII. CONCLUSION As the wireless communications technologies evolve dramatically, the recent research focus has shifted to the development of 4G mobile systems. Instead of developing a new uniform standard for all wireless communications systems, 4G communication networks strive to seamlessly integrate various existing wireless communication technologies. The 4G technology with BYOD over cloud computing may help efficient usage of wireless networks for all the applications which may be helpful for the mankind. REFERENCES [1]Roberts, M L et al. Evolution of the Air Interface of Cellular Communications Systems toward 4G Realization. IEEE Communications Surveys and Tutorials, 8 (1), 2006. [2]:"http://www.mobileinfo.com/3G/4GVision&Technologies.htm [3]F. Bader, C. Pinart, C. Christophi, E. Tsiakkouri, I.Ganchev,V. Friderikos, C. Bohoris, L. Correia, L.Ferreira. ―User-Centric Analysis of Perceived QoS in 4G IP Mobile/Wireless Networks‖. PIMRC'2003, Pp.x.1-x.7, 7-10 September 2003. Beijing, China. ISBN 0-7803-7823-7. [4]Ivan Armuelles, Tomas Robles,Ivan Ganchev, Mairtin O‘droma,Hakima Chaouchi,Matthias Siebert."On Ad Hoc Networks in the 4G Integration Process". [5]"http://www.4gamericas.org/index.cfm?fuseaction=page§ionid=361 ". [6]"http://www.ehow.com/info_12053800difference-between-3g-4g-5gdownloading.html#ixzz1tnEQ7zMb". [7]K. Kumaravel."Comparative Study of 3G and 4G in Mobile Technology",IJCSI International Journal of Computer Science Issues, Vol. 8, Issue 5, No 3, September 2011 ISSN (Online): 1694-0814. [8] F. Ghys and A. Vaaraniemi, ―Component-based Charging in a Nextgeneration Multimedia Network,‖ IEEE Commun. Mag., vol. 41, no. 1, Jan. 2003, pp. 99–102. [9] S. Higgenbotham, Countdown to 4G: who‘s doing what, when, 2008. [10] J. Fleck, ―A Distributed Near Real-time Billing Environment,‖ Telecommun. Info. Net. Architecture, 1999, pp. 142–48. [11] P. Taylor, AT&T to roll out 4G network, 2009. [12] D. Tipper et al., ―Providing Fault Tolerance in Wireless Access Networks,‖ IEEE Commun. Mag., vol. 40, no. 1, Jan. 2002, pp. 58–64. [13]Payaswini P, Manjaiah D.H,"Challenges and issues in 4G – Networks Mobility Management",International Journal of Computer Trends and Technology (IJCTT) - volume4 Issue5–May 2013. [14]"http://www.academia.edu/3713857/Comparative_study_between_the_gene rations_of_mobile_communication_2G_3G_and_4G [15] Y.S. Rao, Wing-Cheong Yeung, and Ani1 Kripalani, ―Third- Generation (3G) Radio Access Standards‖, IEEE 2000. [16] 5 benefits of BYOD with cloud computing, available at: CloudTweaks.com.htm [17] HP BYOD solution, Technical white paper.
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