Roaming in Wireless Networks

Scenarios (Global System for Mobile Communication (GSM)) Part 2

Call establishment The call can be established only if the MS is ON and successfully registered in a network by the location update procedure, as explained in the previous section. There are two different scenarios for call establishment, i.e., mobile originated call (MOC) and mobile terminated call (MTC). Figure 3-22 Cipher mode procedure. Mobile originated […]

GPRS Overview (General Packet Radio Service)

GSM offers circuit-switched data services at lower rates. As a standard form, it is limited to 9.6 Kbps. This is obviously not enough for many applications. It takes a long time to setup and is too slow. A user occupies one timeslot out of the available 8 timeslots in a frame during the entire duration […]

GPRS Services (General Packet Radio Service)

GPRS is designed to address the needs of the mobile data market, which is growing at a fast pace. There are many applications available both for businesses and general users. Generally, these applications are divided into two high-level categories, i.e., horizontal and vertical applications. Horizontal applications Horizontal applications are designed for businesses and general consumers […]

GPRS Network Architecture (General Packet Radio Service)

The GPRS network is designed as an overlay network on an existing GSM network. Additional components are added to handle packet data and interface to external PDNs. Figure 4-1 shows the additional components required to implement GPRS. It also shows the interfaces between new components, as well as the existing GSM components. Anew mobile station […]

Interfaces and Protocols (General Packet Radio Service)

User plane Figure 4-3 shows the protocol architecture of the GPRS user/transmission plane. The user plane provides user information transfer and associated signaling procedures, e.g., flow control and error detection and correction. GGSN-SGSN. The user data packets arriving at the SGSN from the MS or at the GGSN from the external PDN are encapsulated before […]

GPRS Identities (General Packet Radio Service)

International mobile subscriber identity (IMSI) is a unique identifier for a GSM/GPRS subscriber in a PLMN.Likewise, in GPRS, the MS is assigned temporary identities. These are used at different interfaces and serve specific purposes. P-TMSI A packet temporary mobile subscriber identity (P-TMSI) is assigned to a GPRS MS at the time of GPRS attach. Like […]

GPRS Procedures (General Packet Radio Service) Part 1

Mobility management Mobility management states. The mobility management (MM) function is to support the mobility of user terminals. The MM activities related to a GPRS terminal are characterized by one of the three different states, i.e., IDLE, STANDBY, and READY. Figures 4-9 and 4-10 illustrate the MM state models of the MS and the SGSN, […]

GPRS Procedures (General Packet Radio Service) Part 2

Session management MS-initiated PDP context activation. Once the MS is attached to the GPRS network, it can send and receive SMS. The MS must perform PDP context activation to use other GPRS services such as Internet access, intranet access, email, and MMS. This is required to establish a tunnel between the MS and the requested […]

3G Specifications (Third Generation Networks)

"Third generation" (3G) is a new network technology being deployed in many mobile networks today. The motivations to develop a new technology when existing wireless technologies are quite mature and serving users very well are these: ■ Demand for high-speed data ■ Capacity limitations of existing networks ■ Demand for seamless roaming worldwide ■ Demand […]

UMTS Network Architecture (Third Generation Networks)

The UMTS network is divided into two logical networks, i.e., core network (CN) and radio access network (RAN). The CN and RAN are connected via an open interface. The network architecture is continuously evolving to enable a smooth transition from 2G to 3G, leveraging existing and new technologies. Several specifications based on this evolution have […]

← Previous Entries

Next Entries →