The Gateway GPRS Support Node (GGSN) is a main component of the GPRS network. The GGSN is responsible for the interworking between the GPRS. Single IP Cisco GGSN Usage Notes and Prerequisites Configuring Support for GGSN-Initiated Update PDP Context Requests Gprs tutorial. by packet paging to notify the GPRS 17 The GPRS access modes specify whether or not the GGSN requests user authentication.

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What is mostly of interest here is: In the standards, transparent access is defined to be when the GGSN does not participate in user authentication. These mobile stations are backward compatible for making voice calls using GSM.

On the other hand, this access mode is most suitable for services that require minimum interaction between the user and the terminal in order to set up connectivity. In addition, it carries two other very important pieces of information: In principle, an operator may tune the GTP timers and retransmission attempts for create PDP context requests to allow for the latency associated to “IP with Protocol Configuration Options” in setting up tunnels, but this is not a generally safe measure and also does not offer sufficient guarantees to provide acceptable service also when the user is roaming to networks that do not adopt the same tuning of GTP parameters.

Accordingly the introduction of GPRS technology saw the addition of some new entities within the over network architecture. In this case the network has no control over them, nor can it act as a proxy to avoid inefficient usage of radio resources. This access mode based on IP PDP type allows for the same layer two or tunneled connectivity to the network associated to the APN as in the Simple IP case, but it adds the capability to perform user authentication for network access based on a secret shared between the administrative entity of the external network and the end user, thus allowing for a stricter level of security than Simple IP mode.


As a part of the roaming agreement, the way the GTP ggdn integrity is guaranteed may be subject to negotiation and definition. Network-initiated PDP context activation.

GPRS – Architecture

This constitutes a really simple setting that can also guarantee a sufficient level of end-to-end security when the L2TP tunnels are secured via IPSec transport mode and PPP encryption is negotiated. A number of new elements are ggsm for the network, but these can operate alongside the existing elements meaning that the GPRS capability is an upgrade to the network and not a completely new network structure.

From this it can be seen that it is very similar to the more basic GSM network architecture, but with additional elements. After this we are saving current changes to configuration file using command write to make this policy persistent. This has spurred a number of activities within the GSM Association International Roaming Expert Group IREG that helped in fine-tuning technical ttutorial in providing roaming to subscribers across networks, across countries, and for different services.

When a particular VPN service only applies to some release of the system, we will make that explicit. In the opposite direction, packet data from the mobile is routed to the right destination network by the GGSN. Only remote subscription data will be used. Charging and Billing If the expectations of MVPN services to become one of tjtorial mainstream cash generators for wireless service providers are ever realized, accounting data collection and billing information generation will surely become some of the most critical aspects in the successful and profitable delivery of MVPN services.

Password management criteria for L2TP tunnels should also be included.

GPRS Network Architecture Tutorial

Therefore, it may happen that this would negatively impact the radio resources usage and make the bill for the user undesirably more expensive. A variety of MS can exist, including a high-speed version of current phones to support high-speed data access, a new PDA device with an embedded GSM phone, and PC cards for laptop computers.

Availability of the MVPN service when roaming and associated roaming fees. This allows for the evolution of the authentication protocols used without the need of changing the NAS and AAA infrastructure.


OpenBSC GPRS – Cellular Network Infrastructure – Open Source Mobile Communications

For the CSD case, NAS telephone numbers, as well any conditions associated with user sessions termination upon idle timeouts. All IMSIs will be accepted. The few exceptions are:. Along with the packet data transport the GSM network accommodates multiple users to share the same air interface resources concurrently. Here is how this problem can be eliminated: Roaming was initially conceived to enable service across countries, but as soon as market deregulation took place, regulators forced incumbent operators to provide access to their own infrastructure to new entrants on the basis of regulated roaming rates to alleviate entry barrier problems and promote competition on a fair basis.

Broadly speaking, this access method would map to Simple IP access mode in our taxonomy see below the section providing a detailed tutoriall of this access modeshould we elect to engage in terminology ggzn. In the example acl-only is selected as authorization policy. Within this security-parameters-related section of the SLA, the handling of subscriber profiles and data should be described.

The Serving GPRS Support Node is responsible for authentication of GPRS mobiles, registration of mobiles in the network, mobility management, and collecting information on charging for the use of the air interface.

For cases that rely strictly on the HLR subscription data for user authentication, integrity protection of GTP signaling from the visited SGSN to the home GGSN is required, so that the Selection Mode IE cannot be altered and therefore is expected to be valid, since it is generated by tutorlal visited network that has a trust relationship with the home network.

The BTS can also require a software upgrade but typically does not require hardware enhancements.