Operation Manual

NetWAYS/ISDN – Glossary 67
Keep-alive packets
Keep-alive packets are sent periodically throughout the net-
work to verify whether a client is still active. If the sending
station receives no response, it clears down the logical con-
nection.
LAN (Local Area Network)
A computer network limited to a given location, such as a
company site or a government agency’s office building. Re-
mote computers can use appropriate software (such as
NetWAYS/ISDN) to join a LAN over ISDN, ADSL, GSM or VPN
connections.
Logical ISDN connection
A logical ISDN connection refers to the situation in which two
computers consider an ISDN connection between them,
which can be dialed up in one or two seconds, to be virtually
continuous. An actual B-channel connection need not be
continuously active during the logical ISDN connection.
Throughout the entire duration of the logical ISDN connec-
tion, NetWAYS/ISDN maintains all the connection parame-
ters that were negotiated when the physical connection was
first dialed up. These parameters include the network proto-
cols used, the authentication requirements, spoofing
mechanisms and channel bundling. If data is queued for
transmission when no B-channel connection is active, the
B channel can be dialed up immediately.
Logical ISDN connections to the Internet are not supported
by Internet Service Providers.
Logical network connection
A logical network connection refers to a network-layer con-
nection between two LANs, or between a LAN and a remote
client. The connecting router recognizes the remote system
as long as the logical network connection persists.
A logical ISDN connection constitutes a record of all the con-
nection information negotiated at the initial connection set-
up between the systems at either end of an ISDN WAN link.
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