Download Mobile VPN for CDMA 3G Data Networking

S.D.M. College Of Engineering And Technology, Dharwad.
Mobile VPN for CDMA 3G Data Networking.
Seminar by:
Prashant K. Jinnur.
Roll No
:
731.
Reg No
:
2SD98CS037.
Examiner :
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Introduction
The concurrent evolution of computing, microelectronics,
wireless data technologies, and the Internet have given rise to a new trend in global
telecommunications - data mobility. There are now about 100 million hosts
connected to the Internet, and this number is almost doubling yearly. With mobile
subscribers expected to surpass one billion by 2003 (about half of which will be
worldwide business users), wireless data is definitely a communications
technology whose time is fast approaching.
These skyrocketing subscriber numbers combined with recent
technology advances are generating fast growing interest in the emerging Third
Generation (3G) wireless data standards, which among other things specify the
higher data rates necessary for wireless traffic. As this technology converges with
the exponential growth of the Internet, network-based, Mobile Virtual Private
Networks (VPNs) will become the major enabling technology for communicating
business information via public networking infrastructures .Indeed businesses
today already are looking to wireless carriers for Mobile VPNs (and other valueadded IP services) as they attempt to cope with global on-demand
communications, complex applications, productivity requirements, and shortages
of IT talent. In the next few years, an enormous market opportunity clearly awaits
wireless carriers who can meet demands for such advanced services.
CDMA (Code Division Multiple Access) 2000 technology will
play an important role in the new mobile markets. By enabling wireless carriers to
use resources more efficiently and to offer significantly higher data rates than
previous technologies, CDMA 2000 frameworks will provide the MVPN support
essential for success.
Hence we will examine aspects of the design and
implementation of MVPNs within CDMA 2000 3G cellular systems frameworks.
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Wireless Data Concepts: Packet vs. Circuit
CDMA, Time Division Multiple Access (TDMA), and
Global System for Mobile Communications (GSM) cellular systems supporting
circuit-based data, provide users with low-speed data connectivity. These
technologies have a number of drawbacks including poor utilization of airinterface resources, limited availability, use of wasteful dial-up connection
technology, and limited infrastructure integration. Packet technologies such as
Mobile IP and GPRS were designed to overcome these limitations.
With traditional, circuit-switched wireless data services,
dedicated circuits at the physical layer are allocated to subscribers whether or not
they are being used. In contrast, wireless packet data services allow subscribers to
send and receive data without maintaining dedicated circuits.
Existing wireless packet data technologies that address
these and other problems largely are conceptually similar and based on various
tunneling mechanisms. (See Figure 1.) In all of them tunnels are dynamically
established between the mobile node’s temporary point of attachment to the
Internet and its home network (where the user is logically assigned the IP address).
Figure 1. Wireless Packet Data Concepts
An alternative approach terminates tunnels at an Intermediate Gateway node that
acts as an anchor point. User packets then may either be tunneled back to the home
network (using another tunnel or a Link Layer technology) or directly delivered to
a local interface for forwarding. As mobile nodes dynamically change their points
of attachment to the network (traveling through certain area of the country from
Mobile Switching Center (MSC) to MSC for example), tunnels are dynamically
established between the home and visited networks.
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Mobile VPNs
Today’s growing mobile workforce — and its attendant
requirements for remote data access — is forever changing the telecommunications
industry. Telemetry and other un-tethered equipment, traveling sales forces, field
maintenance crews, telecommuters, and other mobile professionals are driving
demands for secure, anytime/anywhere access to corporate intranets, databases and
e-mail servers. In this new environment, productivity gains (or losses) will be
directly linked to the information delivery process.
In the roughly ten years since their emergence, data VPNs
typically have been implemented at the data link layer using Frame Relay and
ATM networking technologies. Now VPN services based on IP and the use of the
Internet are quickly gaining public interest and market acceptance. VPNs are
evolving from voice to data services and from wire line to wireless data networks.
Like traditional VPNs, IP VPNs utilize shared facilities to emulate private
networks and deliver reliable, secure services to end-users.
Mobile IP-based VPNs use a combination of R-P interface
and Mobile IP tunneling protocols on the dynamic “mobile” tunnel side and IETFdefined tunneling protocols on the “fixed” side. (See Figure 2.)
Figure 2. Mobile VPN
GPRS and UMTS-based VPNs use a combination of GPRS Tunneling
Protocol (GTP) on the dynamic “mobile” tunnel side and IETF-defined tunneling
protocols on the “fixed” side. The business benefits of deploying
Mobile VPNs (MVPNs) are numerous. MVPNs provide
remote workers with constant, media independent connectivity to corporate sites or
to the ISPs and ASPs of their choice. MVPNs also enable businesses and ISPs to
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outsource mobile remote access — thereby eliminating the costs of purchasing and
supporting the infrastructure while maintaining full control over address
assignments and user authentication and security. In this way, corporations can
leverage the Internet to provide anytime/anywhere, secure connectivity to remote
offices, SOHOs, mobile employees, e-commerce and extranet business partners
over public network infrastructure. By enabling always on connectivity, there is the
potential to enhance relationships with customers, business partners, and suppliers
by sharing in real time information.
Implementing Mobile VPNs
IP tunneling is central to implementing MVPN. In addition to
traditional wire line VPN features, MVPN includes a set of mechanisms that use
dynamic IP tunneling to support user mobility.
IP tunnels are paths that IP packets follow while encapsulated
within the payload portion of another packet. These encapsulated packets are sent
to destination endpoints from originating endpoints via public (non-secure)
channels. Tunnels also can exist on a link layer, providing encapsulation for nonroutable protocols, such as Layer 2 Tunneling Protocol (L2TP) for Point-to- Point
Protocol (PPP).
There are two basic tunneling methods for implementing IP VPNs — end-to-end
or “voluntary;” and network- based or “compulsory.” MVPNs based on voluntary
tunneling are implemented by providing users with public Internet access, and
subsequently with access behind corporate firewalls via available tunneling
techniques that allow secure data transmission. (See Figure 3.) The end-to-end
tunnel used in this case must exist for the duration of the session only.
Figure 3. Mobile VPN: Voluntary Tunnel
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While voluntary tunneling provides a simple, secure end-to-end
solution for access to private networks, it also leads to extra encapsulation
overhead over last-hop wireless links. Also, this is a less efficient, more costly
use of radio resources. In volume-based charging scenarios for instance, such
overhead could significantly increase corporate costs for remote connectivity.
Voluntary tunneling carries a number of other drawbacks as well.
For example, it requires that mobile nodes be given public addresses allowing
end-to-end transparent IP connectivity. In addition, it requires complex
encryption and decryption algorithms, which can increase the complexity and
cost of mobile devices, which typically have low processing power and are often
battery power consumption limited. Also, with voluntary tunneling, applications
that need to inspect or modify encapsulated packets will be unable to get access
to user traffic. This means that QoS solutions, traffic-shaping mechanisms,
monitoring equipment and firewalls will fail to perform their functions, and
encapsulated (secured) packets cannot be modified by the Network Address
Translation (NAT) protocol.
Network-based “compulsory tunneling,” on the other hand,
provides a more optimal foundation for MVPN solutions. (See Figure 4.) This
tunneling approach assumes that not mobile devices but the wireless operator’s
network infrastructure itself features the intelligence and functionality necessary
for the deployment of MVPNs. This approach assumes that the air interface
owned by the wireless carriers is secure. With “compulsory tunneling,” network
components such as access servers, gateways, etc. (not the mobiles) initiate
tunnels, which typically terminate at the private network behind the firewall.
Compulsory tunnels can be used by multiple subscribers
and can remain active even if no subscriber transactions are in progress (thus
placing fewer burdens on the computing and routing infrastructure). The
compulsory approach to tunneling also assumes the existence of proper
agreements between corporations or ISPs and wireless operators. Service Level
Agreements (SLAs) address the business relationships between service providers
and corporations, while the Security Associations (SAs) or shared secrets used to
generate IP Security (IPSec) session keys address the technical relationships.
IPSec is a group of RFCs dealing with the secure encapsulation of IP traffic.
Compulsory tunnels established through the public Internet
require protection through authentication and encryption. This protection,
however, need not be extended through the radio link but can be implemented
between the tunnel end points only. Security in this scenario is likely to be based
on IPSec, and will include mechanisms for distributing keys such as the Internet
Key Exchange .
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Figure 4. Mobile VPN: Compulsory Tunnel
To implement MVPNs capable of supporting services on a large scale, wireless
data infrastructures will require a new class of platforms that fully comply with
3G wireless standards. Such systems will provide the critical ability to rapidly
address demands for business-class IP services. SpringTide 7000 Wireless IP
Service Switch addresses these requirements by leveraging a service-intelligent
architecture, multi-protocol tunnel switching and true virtual routing. This
powerful platform will enable wireless carriers to deliver the industry’s broadest
portfolio of highly available IP services including Mobile Virtual Private
Networks.
CDMA 3G Wireless Data Communications
CDMA 2000 allows the wireless service provider to offer bidirectional packet data transfer using the Internet Protocol. In a CDMA system,
resources are used more efficiently because packet traffic channels are shared
between many simultaneous users. Most importantly, the service provider will be
capable of providing subscribers with higher data rates than were possible with
previous technologies. CDMA 2000 framework also provides full support for
Mobile VPNs. To provide these functionalities CDMA 2000 utilizes both Simple
IP and Mobile IP protocols. From user prospective the difference between Simple
IP and Mobile IP is that the mobile device must support the MIP protocols, which
are not supported intrinsically by standard operating systems .
MIP specifies data mobility without the need for users to change IP
addresses when traveling to different coverage regions or switching to different
networking mediums. MIP must be implemented in three main functional
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entities: Home Agent (HA), Foreign Agent (FA), and the mobile IP client
implemented at the mobile node.
MIP allows users to roam across large geographical boundaries while
maintaining packet data sessions with the same IP address. It also provides the
ability to securely tunnel into private intranets that support Mobile IP (i.e. those
supporting MIP Home Agents (HA) inside the firewall). In other words, the
routing devices terminating dynamic tunnels may be located within wireless
operator networks as well as within corporate networks. (See Figure 5.)
Figure 5. Lucent CDMA 3G Architecture.
Mobile node home addresses (located on the mobile node home
network), are permanently assigned IP addresses similar to those assigned to
nodes in “fixed” IP networks. When mobile nodes are attached to their home
networks (linked to HAs), packet routing happens exactly as it does in fixed IP
networks. When nodes leave the home network, however, their locations are
represented by their “Care-of” addresses (CoA) which are assigned by the FA (or
by the node itself in some cases). The FA serves as the
default router for mobile nodes while they are connected to foreign networks.
CoAs change as the node travels between different foreign networks.
HAs and FAs constantly advertise their presence in the networks in question to
the traveling nodes. In this way, traveling mobile nodes are able to determine that
that they are connected to a foreign network. Mobile nodes acquire CoAs from
the respective FAs, which also are responsible for registering the address
with the node’s HA. The tunnel between FA and HA is negotiated at this time.
The IP packets sent to the mobile node will be intercepted by the HA and then
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forwarded to the CoA at the FA through the tunnel created in the previous steps.
The packets then are extracted at the tunnel termination point and forwarded
to the mobile node. The packets sent by the mobile node (in the opposite
direction) are routed by the serving FA directly to their destinations without the
need to tunnel them back to the HA. When the HA intercepts the packet destined
for the mobile node (which is “away from home”), it looks up the corresponding
binding that was created during the FA/HA tunnel establishment phase. IP
packets then are tunneled to the CoA, regardless of whether they are FA or
mobile-node based. The FA receives the tunneled packet, de-tunnels
(decapsulates) it, matches the packet destination address to that of the
registered node, and forwards it to its final destination through the appropriate
interface. In the case of co-located addresses, de-tunneling is performed at the
node itself from which the contents of the IP packet are then sent up the protocol
stack. When the Mobile IP client is connecting to its home network over a
wireless medium, Mobile IP requires a second layer of connectivity between the
mobile node and the FA.
Implementing Mobile IP in CDMA 3G allows for seamless
packet data mobility. (See Figure 6.) The Packet Carrying Function (PCF) in
CDMA 3G provides the following functionality:
• Terminating of PPP
• Handling of MIP agent advertisement and solicitation messages
• Managing of link layer connections with mobiles
• Handling of Frame Relay links to MSCs
• Processing of and response to, MIP agent solicitation messages from mobiles
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Once Frame Relay connections are established, the PCF simply relays
IP packets between the mobile device and the currently attached PDSN. The most
important function of PCF is to provide micro-mobility support, which is
accomplished by allowing PCF transfers while keeping the mobile anchored on
the same PDSN. Since CDMA 3G supports both IP and MIP, PDSN must include
support for the scalable tunnel switching of MIP, IP in IP, and L2TP tunnels.
Because it is based on virtual router architecture, the PDSN easily
accomplishes this level of support.
Lucent PDSN and HA for Mobile VPN services
The issue of implementation wireless data platforms capable of
providing scaleable advanced IP services is important for both established and
emerging wireless operators wishing to differentiate their wireless data offering
and target business customers. The platform design must cost-effectively
incorporate the best features of both data and wireless equipment, simultaneously
providing the highest degree of reliability and scalability. 3G Wireless data
platforms like PDSN and HA can be implemented on general-purpose computer
platforms with software routing capability, such as UNIX-based solutions or
dedicated routing platforms, such as Remote Access Server (RAS), Routers or
Multi-Service IP Switch.
RAS devices are used to aggregate the low speed connections such
as modem or ISDN calls from the PSTN and a small number of T1’s or T3’s.
Typical RAS is designed to handle a specific number of sessions, which are
physically limited by a known number of interfaces with a known maximum
throughput. It is relatively costly and its resource allocation strategy and
Operating System are usually not optimized for routing and tunneling support.
Multi-service IP switch routers (such as SpringTide 7000 IP Service Switch) are
designed to address general routing solutions shortcomings in VPN area. Such a
device typically is capable of terminating and switching hundreds of thousands
individual tunnels while applying the necessary service processing functions
to each user traffic flow. In such a device traffic enters and exits over any highspeed interfaces deployed within CDMA carrier’s network such as ATM, or FR.
Multi-service IP switches are designed to handle as many tunnels as possible over
each of their interfaces and equipped with carrier class features certification and
full redundancy. Traffic flows are conveyed in virtual connections that are
aggregated over these interfaces. A virtual connection may be a virtual circuit, a
PPP session, or an IP tunnel. These devices are also capable of aggregating and
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terminating ten and even hundreds or thousands of user communication (PPP)
sessions.
Wireless packet data networks based on dynamic tunnel switching require
routing platforms capable of aggregating large numbers of user communication
sessions and multitude of IP tunneling methods, tunnel switching, firewalling,
BGP4 and other advanced IP services will also be required by wireless data
network operators.
The SpringTide 7000 Wireless addresses these needs by supporting all required
types of tunneling, encryption, and authentication to provide flexible, highperformance Mobile VPN services. SpringTide Wireless 7000 is equipped with
all the necessary hardware and software to terminate, authenticate, encrypt, and
route a multitude of VPN tunneling technologies including Mobile IP, R-P,
IPSec, IPIP, L2TP e.t.c. Wireless carriers can use the tunneling technology of
their choice and easily scale their VPN services as they grow their businesses. To
provide support for advanced IP services The SpringTide Wireless IP Service
Switch employs the virtual router approach to building network-based VPNs.
The SpringTide “Virtual Router” Approach
The SpringTide 7000 Wireless IP Service Switch is based on a switch
architecture that uses a virtual router concept in which services are dynamically
created across “virtual”-rather than physical-routers. Virtual routers provide the
secure, segregated environments required for delivering business-quality IP
services and for building network-based VPNs for advanced IP services.
Within the virtual router, individualized service definitions for
bandwidth, priority, and security are retrieved from policy directories and
provisioned on either a per-subscriber or per-traffic flow basis. Virtual routers
have their own routing tables and separate code-address space with memory,
which prevents any one virtual router from affecting other virtual routers. The
SpringTide 7000 Wireless system resources are dedicated to each configured
virtual router. Each virtual router has dedicated resources including allocated
memory and instruction cycles that handle updates, make necessary changes to
forwarding tables, and send them to be stored on — and utilized from — the local
virtual router.
Virtual routers also employ highly efficient methods of calculating
and maintaining routing and forwarding tables. Several algorithms can be
executed simultaneously within this architecture, each running individually
without affecting the other. Each virtual router is allocated its own dedicated
CPU cycles, routing tables, clients and local pools of IP addresses.
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Lucent CDMA VPN Solutions
CDMA 3G architecture allows for two basic approaches to providing VPN
services: Simple and mobile IP.
Simple IP MPLS-Based VPN
Because of its traffic engineering capabilities, MPLS (Multi-Protocol
Label Switching) is fast emerging as an attractive option for forwarding IP
packets over multi-service backbones in wire line networks. MPLS-based VPNs
are relatively easy to implement on PDSN based on routing platforms and, for
this reason, are being heavily promoted by traditional router manufacturers.
MPLS labels include distinct VPN identifiers that associate packets
with private routing domains. This maintains both address secrecy, and the ability
to handle duplicate or overlapping addresses. MPLS labelset- up protocols such
as RSVP (Resource Reservation Protocol) can communicate dynamic
reachability information through the MPLS network
The fundamental building block for SpringTide 7000 Wireless based VPN is
Virtual Router (VR). Virtual routers provide the secure, segregated environments
required for delivering business-quality IP services.
Figure 7. CDMA 3G VPN (Simple IP)
Each virtual router has its own routing information base (RIB),
forwarding information base (FIB) and a separate MPLS data forwarding engine
with its own code address space with memory, which prevents any one virtual
router from affecting other virtual routers. Within each virtual router,
individualized service definitions for bandwidth, priority, and security are
retrieved from policy directories and provisioned on either a per-subscriber or
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per-traffic flow basis. The performance of one virtual router does not affect other
virtual routers in the system.
The Lucent MPLS MVPN architecture consists of two logical layers Service layer and Network layer. The virtual customer equipment (VCE)
supports the service layer. The provider router acts as a virtual label edge router
(VLER) and interfaces with the SP backbone. The VLER supports the network
layer. These two layers are tightly integrated and provide an elegant solution to
building VPN. The beauty of this architecture is in its flexibility and scalability.
The flexibility is provided in the VPN management. The VR maintains separate
route, forwarding and MIB database. The database separation of each VR allows
the wireless carrier and/or its corporate customers to monitor traffic statistics,
configure policies to build dynamic on-the-fly extranets to corroborate with their
business partners.
One method for deploying CDMA 3G VPNs is using a combination of
BGP-4 and MPLS protocols defined in RFC 2547. This implementation is
relatively straightforward when PDSN supports both BGP-4 and MPLS. PDSNs
(or Provider Edge (PE) devices) are tasked with associating Customer Edge (CE)
devices into a VPN group by virtue of common MPLS labels that combine the
VPN ID with address prefixes used within each private routing domain. The
PDSN PE has knowledge of all of the networks to which it is directly connected
via CE devices. This includes knowledge of which networks belong to which
private domain. Using that information, each PDSN (PE) builds and maintains its
forwarding table. The information is then shared with other PE routers by using
techniques (attributes, communities, new address “families,” etc.) supported by
the BGP-4 standard. With a complete set of reachability information, as well as
the knowledge of which networks belong to which VPN, the PE routers can label
packets with the information necessary to forward them through the MPLS core
over LSPs. Although MPLS can be combined with IPSec for security and with
L2TP to utilize the advantages of PPP, this approach can significantly degrade
network performance.
Mobile IP VPN
In the case of Mobile IP service, the VPNs are supported by Foreign
Agent function in the Lucent PDSN, which provides for secure Mobile IP
tunneling to a Home Agent that resides within a private Intranet (See Figure 8.)
All of the traffic is tunneled between the HA and FA, through an “IP-in-IP”
tunnel, and the IP address of the mobile is assigned from the address space of
their HA network (either statically provisioned, or dynamically assigned by the
HA at the beginning of the session). The mobile must first register with the HA
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and FA (via authentication by both HA and FA AAA servers linked via AAA
infrastructure) to establish the MIP tunnel over which their traffic is delivered.
Mobile IP tunnels in this scenario must be secured by. During a setup of an IPSec
secured tunnel between FA and HA, Internet Key Exchange (IKE) protocol is
used to verify the identity of FA and HA. The security key association may be:
– Statically configured secret for MIP HA/FA authentication extension
– Statically configured IKE pre-shared secret
– Dynamic pre-shared IKE secret distributed by home AAA
– Public Key Information (PKI) with certificates.
Figure 8. CDMA 3G VPN (Mobile IP)
The static MIP HA/FA authentication extension supersedes the static IKE preshared secret, which supersedes the dynamically distributed IKE secret, which
supersedes the PKI certificate in order of precedence.
The customer network must now support Mobile IP Home Agent terminating
Mobile IP tunnels established by a PDSN/FA currently serving mobile user in its
visited network. All of the traffic is tunneled between the HA and FA, through an
“IP-in-IP” tunnel, and the IP address of the mobile is assigned from the address
space of their HA network (either statically provisioned, or dynamically assigned
by the HA at the beginning of the session). The mobile endpoint must first
register with the HA and FA (being authenticated by each) to establish the MIP
tunnel over which their traffic is delivered. Private network access is also
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supported by allowing the HA to reside within the private network and by
invoking IPSec security on the Mobile IP tunnels.
VPN Summary: The Virtual Router Approach
The virtual PDSN and HA, as implemented on SpringTide 7000 Wireless IP
service switching platform, is essentially a collection of individual PDSN/HAs
upon which a variety of advanced IP services can be built. With the virtual router
approach, customers essentially lease network resources that are located on the
wireless operator owned HA. The Mobile VPN behaves and is managed in much
the same way that an actual physical private router network would behave and be
managed. Some of the services and functionalities found in the virtual router
approach, which are available individually to each of more then 1000 virtual
PDSN/HAs provisioned in the SpringTide 7000 platform, are listed as follows:
• IP routing, including the use of a variety of routing protocols (RIP, OSPF, BGP4, etc.) and route policies, over high-speed cell or packet media
• Mobile IP Session Termination
• R-P Session Termination
• PPP Tunneling (PPTP and L2TP) initiation and termination
• QoS-enabled forwarding
• Stateful Firewall (as well as basic packet filtering)
• IPSec Tunnel initiation and termination
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Conclusion
In summary, virtual routing approach provides multiple functionalities offered by
Traditional PDSN, RAS, ATM Edge Routers, Customer Premise-based VPN
appliances, Firewalls, and QoS/MPLS enabled routers, etc. Virtual routing-based
MVPN utilizing the SpringTide 7000 Wireless platform effectively allows
wireless operator to deploy any of the existing VPN options without the
drawbacks associated with individual technologies.
Glossary
3G . . . . . . . . . . . . . . . . . . . . . Third Generation
3GPP . . . . . . . . . . . . . . . . . . . 3rd-Generation Partnership Project
AAA . . . . . . . . . . . . . . . . . . . Authentication Authorization, Accounting
ATM . . . . . . . . . . . . . . . . . . . Asynchronous Transfer Mode
AuC . . . . . . . . . . . . . . . . . . .Authentication Center
BS . . . . . . . . . . . . . . . . . . . . . Base Station
BTS . . . . . . . . . . . . . . . . . . .Base station Transceiver System
CDMA . . . . . . . . . . . . . . . . . Code Division Multiple Access
CGF . . . . . . . . . . . . . . . . . . . Charging Gateway Function
EDGE . . . . . . . . . . . . . . . . . . Enhanced Data rates through Global Evolution
EIR . . . . . . . . . . . . . . . . . . . . Equipment Identity Register
GGSN . . . .. . . . . . . . . . . . . . Gateway GPRS Support Node
GPRS . . . . . . . . . . . . . . . . . . General Packet Radio Service
GSM . . . . . . . . . . . . . . . . . . . Global System for Mobile Communications
GTP . . . . . . . . . . . . . . . . . . . GPRS Tunneling Protocol
HLR . . . . . . . . . . . . . . . . . . . Home Location Register
IETF . . . . . . . . . . . . . . . . . . . Internet Engineering Task Force
IMEI . . . . . . . . . . . . . . . . . . . International Mobile Equipment Identity
IMSI . . . . . . . . . . . . . . . . . . International Mobile Subscriber IdentityIMT-2000
IPSec . . . . . .. . . . . . . . . . . . .IP security
ISP . . . . . . . . . . . . . . . . . . . . Internet Service Provider
ITU . . . . . . .. . . . . . . . . . . . .International Telecommunication Union
LCS . . . . . . . . . . . . . . . . . . .Location Services
L2TP` . . . . . . . . . . . . . . . . . . Layer 2 Tunneling Protocol.
LAN . . . . . . . . . . . . . . . . . . . Local Area Network
LNS . . . . . . . . . . . . . . . . . . .L2TP Network Server
MAN . . . . . . . . . . . . . . . . . . Metropolitan Area Network
MSC . . .. . . . . . . . . . . . . . . .Mobile-services Switching Center
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NodeB . . . . . . . . . . . . . . . . . UMTS Base Station
OA& M . . . . . . . . . . . . . . . .Operations, Administration and Maintenance
PDP . . . . . . . . . . . . . . . . . . .Packet Data Protocol
PSTN . . . . . . . . . . . . . . . . . . Public Switched Telephone Network
PVC . . . . . . . . . . . . . . . . . . . Permanent Virtual Circuit
QoS . . . . . . . . . . . . . . . . . . .Quality of Service
RA . . . . . . . . . . . . . . . . . . . .Routing Area
RADIUS . . . . . . . . . . . . . . . .Remote Authentication Dial-in User Service
RAS . . . . . . . . . . . . . . . . . . .Remote Access Server
RNC . . . . . . . . . . . . . . . . . . . Radio Network Control
RNS . . .. . . . . . . . . . . . . . . . . Radio Network Subsystem
SGSN. . . . . . . . . . . . . . . . . . Serving GPRS Support Node
SIM . . . . . . . . . . . . . . . . . . . . Subscriber Identity Module
SMS . . . . . . . . . . . . . . . . . . . . Short Message Service
SRNS . . . . . . . . . . . . . . . . . . . Serving RNS
SVC . . . . . . . . . . . . . . . . . . . . Switched Virtual Circuit
TCP . . . . . . . . . . . . . . . . . . . . Transmission Control Protocol
TIA . . . . . . . . . . . . . . . . . . . . Telecommunication Industry Association
TDD. . . . . . . . . . . . . . . . . . .Time Division Duplex
TDM . . . . . . . . . . . . . . . . . . . Time Division Multiplex
TDMA……………………….Time Division Multiple Access
UDP . .. . . . . . . . . . . . . . . . . .User Datagram Protocol
UE . . . . . . . . . . . . . . . . . . . . . User Equipment
URC . . . . . . . . . . . . . . . . . . . Universal Radio Controller
USIM . . . . . . . . . . . . . . . . . . User Service (or Subscriber) Identity Module
UMTS . . . . . . . . . . .. . . . . . . Universal Mobile Telecommunications System
VLR . . . . . . . . . . . . . . . . . . . Visitor Location Register
VPN . . . . . . . . . . . . . . . . . . . Virtual Private Network
Bibliography
The information required to present this seminar was downloaded from the
website of Lucent Technologies and also from various other sites relating to this
topic.
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