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EXP Computer PathBuilder S200 User Manual

Page 107

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Bridging

103

T0008-16F

Release 5.2M

LLC2 Local Termination

Proper LT
configuration

Figure 52 shows a Token Ring LAN properly configured for Local Termination.

Figure 52. Example of Proper LT Configuration

Local Termination running on PathBuilder S200 series switch bridges 1, 2, and 3 at
the edge points of the network provide a simple solution to congestion and
bandwidth problems across the entire network.

LLC Protocol

LLC is a link layer protocol used in IBM environments and defined in the IEEE802.2
LAN model. Its function is to establish, maintain, and terminate the logical link
between adjacent stations in a network.

LLC Frame
Description

There are three types of LLC operations:

LLC2 Frame
Description

Logical Link Control 2 (LLC2) is a connection-oriented, acknowledged protocol.
LLC2 requires a connection setup between two LAN devices. LLC2 is based on the
HDLC protocol and is used to transport SNA traffic, as well as other protocols.

1

2

SNA

FEP

LLC2

Keepalives/Acks

LLC2

Keepalives/Acks

CC

3

CC

LLC2

Keepalives/Acks

Type

Name Description

Type 1

LLC1

Unacknowledged, connectionless services

Type 2

LLC2

Connection-oriented services

Type 3

LLC3

Acknowledged, connectionless services