ATM BASICS - Chapter 5 ppt

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Chapter 5

Using ATM to Connect Systems

ATM is commonly used to connect systems. There exits also a number of pro￾tocols and scenarios for interworking between ATM networks. This chapter

introduces signaling flavors and routing concepts, which are deployed in

contemporary ATM networks. In the first place, the chapter covers address￾ing as well as general signaling issues. Then it presents signaling protocols

that are used to setup connections across UNI and PNNI interfaces. Finally

different methods of interworking between ATM networks are discussed.

Connecting systems using ATM must involve the use of ATM addressing

and signaling. Both elements are important parts on the ATM concept.

Addressing actually takes place at two levels: at the ATM level using

VPI/VCI identifiers and at the logical network level. All signaling protocols

assign match VPI/VCI values to ATM address and physical ATM UNI and

/or NNI ports. Every physical ATM UNI port must have at least one unique

ATM address. Both VCCs and VPCs are unidirectional, so signaling proto￾cols must specify traffic parameters separately for each direction of the con￾nections. Note that in addition to signaling operation there is also a need for

routing capabilities necessary to find the optimal route for a connection.