Ubiquitous Wireless Service in Visual C#

Reader QR Code in Visual C# Ubiquitous Wireless Service

Ubiquity refers to the ability of a subscriber to obtain wireless telecommunications services everywhere This does not necessarily imply seamlessness, but it does imply that a subscriber could make and receive calls anywhere, even if the call treatment is different Call treatment refers to the methods that the network uses to handle a call in a certain way Ubiquity is also a characteristic of radio coverage It implies that there are no gaps or holes in a radio coverage area The terms seamless and ubiquitous are often used in conjunction to imply consistent service capabilities, accessible from anywhere and everywhere

Throughout this book we consider the serving system as a single entity encompassing the MSC and VLR functional entities This simplifies the descriptions of ANSI-41 application processes and also is representative of nearly all of the ANSI-41 implementations currently in service However, ANSI-41 s definition of the MSC-to-VLR interface makes the standalone visitor location register a viable network entity For example, ANSI-41 does not assume that the MSC is just a switch without a database or feature control intelligence; if this were the model for ANSI-41, the MSC-to-VLR interface would be burdened with signaling, limiting the potential for separate functional entities On the other hand, the MSC is not given full control of the operation of the serving system; authentication, for example, assigns specific processing duties to the VLR, which makes the idea of sharing a VLR among multiple MSCs particularly attractive So, while we describe automatic roaming

Downloaded from Digital Engineering Library @ McGraw-Hill (wwwdigitalengineeringlibrarycom) Copyright 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website

5:

processes in terms of a single MSC/VLR entity, the reader should keep in mind that the potential for separation exists

Subscriber identification is a set of processes to uniquely identify a wireless subscriber In ANSI-41 networks this identification also pertains to the subscriber s subscription and service profile record maintained at the home location register That is, the identification of a subscriber essentially refers to the identification of a service profile as well A unique subscriber ID is used to register and qualify a subscriber for service; however, the unique subscriber ID is also used to enable all network functions pertaining to an individual subscriber The full unique subscriber ID in most ANSI-41 networks is a concatenation of two unique parameters: the mobile identification number (MIN) and the electronic serial number (ESN) Note that in many ANSI-41 operations, only the MIN is used to identify a subscriber The MIN-ESN combination is used primarily for the registration and authentication functions The international mobile station identity (IMSI) is gaining ground as the successor to the MIN The IMSI offers an improved address space and has particular advantages for international applications of ANSI-41 Mobile Identification Number The MIN is the single most important parameter used in ANSI-41 networks It is a unique 10-digit decimal number programmed into the MS This unique value is assigned to the mobile subscriber by the wireless service provider This MIN is transmitted over the air interface (no matter which radio standard is used) during registration to inform the network of the identity of the mobile station (MS) accessing the network The MIN is also used as a key field to access the wireless subscriber service profile record stored in the HLR (this is why we say that the subscriber ID also identifies a subscription) The service profile record contains the current location and status of the subscriber as well as other information pertaining to the subscription, such as subscribed features and credit status Note that the format of the 10-digit MIN parameter used in the ANSI-41 network is a 40-bit value, with each digit encoded as 4 bits The same 10-digit MIN value transmitted over the air interface (AMPS, TDMA, and CDMA) is specially encoded as two fields: the 24-bit MIN1 and the 10-bit MIN2 The translation between these encoding formats can be performed at either the base station or the serving

Downloaded from Digital Engineering Library @ McGraw-Hill (wwwdigitalengineeringlibrarycom) Copyright 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website