IBM Turboways 155, Инструкция по установке и эксплуатации

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TCP/IP over ATM
Each ATM network interface can have an assigned IP (internet protocol) address.
This assigned network interface can have VPI:VCIs associated with it. This allows a
TCP/IP (transmission control protocol/internet protocol) host, identified by its IP
address, to communicate with multiple TCP/IP hosts on the ATM network.
If your host has more than one IP address, (for example, one ATM interface and one
Token-Ring interface), you must add one network interface for each IP address. The
TURBOWAYS 155 PCI UTP ATM Adapter supports multiple network interfaces.
Configuring with PVCs
PVCs in ATM-attached hosts, gateways, and switches must be configured by users.
For environments requiring the transfer of several protocols over the same VCI or
support for inverse ARP (address resolution protocol) requests, LLC (logical link
control) encapsulation is provided. If LLC support is enabled, the system issues
inverse ARP requests on the VPI:VCI connection to automatically discover the
destination's IP address. This request is issued every minute until the destination IP
address is found. Once the destination IP address is found, inverse ARP requests
are issued every 15 minutes to verify that the connection has not changed. If
automatic destination address discovery by inverse ARP is either declined or not
supported at the destination, the destination IP address must be specified.
Networking with ATM SVCs
Networking with ATM SVCs (swiched virtual circuits) is different from networking with
ATM PVCs. PVCs are created by users during configuration of ATM-attached hosts,
gateways, and switches. These static connections remain established until they are
removed by configuration changes. To establish complete connectivity, a connection
must be configured and maintained from each node to every other node. This
process can become labor intensive as the number of connections grows rapidly with
the addition of nodes. Such complexity is avoided by using SVCs. An IP subnet
using SVCs consists of an ATM switch, an ARP server, and ARP clients. During
network initialization, endpoints automatically open signaling channels to obtain their
20-byte ATM address from the switch. Using the ARP server ATM address provided
by the user at the time of configuration, clients open a connection with the subnet's
ARP server and register both their IP and ATM addresses.
Note: Each subnet requires one ATM ARP server. When a client station needs to
transmit to another station, the ARP server is called. If the destination's IP address
is registered with the server, the destination's ATM address is resolved. The caller
now has the destination ATM address and requests a connection to that station
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Installation and User's Guide