3Com CoreBuilder 9000, User Manual

Page: 327 / 468

Basic ILMI Functions 327
ATM Address Format
An ATM end station address uniquely identifies an ATM endpoint. The
format of an ATM address is modeled after the OSI Network Service
Access Point (NSAP), using the same structure, abstract semantics, syntax,
and preferred binary encoding.
Three different formats are specified:
Data Country Code (DCC) ATM format — International Standards
Organization (ISO). The Data Country Code specifies the country in
which an address is registered. The length of this field is two octets.
The digits of the data country code are encoded in Binary Coded
Decimal (BCD) syntax. The codes are left justified and padded on the
right with the hexadecimal value “F” to fill the two octets. Use this
format for organizations that want to maintain a private numbering
plan that is organizationally based for countries.
International Code Designator (ICD) ATM format — ISO. This
identifies an international organization. The registration authority for
the International Code Designator is maintained by the British
Standards Institute. The length of this field is two octets.
E.164 ATM format
— Specifies Integrated Services Digital Network
numbers. A public network addressing standard that utilizes up to a
maximum of 15 digits.
Multiple Addresses Registered at Port
Each port can have up to 19 ATM addresses registered in its MIB address
table. This occurs when the attached edge device has more than one
ATM-addressable component. For example, edge devices such as
SuperStack II
®
, Switch 2700 and the CoreBuilder 9000 interface modules
can have multiple ATM-addressable Ethernet bridges. The ATM address of
each bridge is registered by ILMI at the port to which the edge device is
connected. (The memory size of the Switch engine is 64 MB.)