IBM SC30-3681-08 manual Using Binary Synchronous Relay Brly, Brly Overview, 561

Chapter 39. Using Binary Synchronous Relay (BRLY)
This chapter describes how to use the Binary Synchronous Relay (BRLY) protocol.
It includes the following sections:
v	ªBRLY Overviewº
v	ªBRLY Considerationsº on page 564
Binary Synchronous Relay (BRLY) is a protocol that encapsulates binary
synchronous communications (BSC) traffic and transmits the traffic across IP
connections. This function permits BSC traffic to ¯ow between BSC peers as if a
BSC connection exists between the peers. The following sections describe BRLY,
some common con®gurations, and how to con®gure a BRLY scenario.
BRLY Overview
BSC connections are similar to SDLC connections in that they consist of a primary
end-point (polling) and a secondary end-point (polled). The connections can be
either point-to-point, where the primary communicates with a single secondary, or
multipoint, where the primary communicates with multiple secondaries. BRLY
supports both physical and virtual multipoint connections.
In this implementation, the primary and secondary BSC devices are connected to
routers which then connect to each other through IP. Figure 30 is a diagram of a
point-to-point and a physical multipoint BRLY con®guration. A physical multipoint
connection is one where all of the secondary devices are on the same physical
connection.
~‡‡‡‡‡‡‡‡‡‡‡‡€			~‡‡‡‡‡‡‡‡‡‡‡‡‡€
ˆPrimary BSC ˆ			ˆ Primary BSC ˆ
ˆ	Device	ˆ	ˆ Device	ˆ
•‡‡‡‡‡ƒ‡‡‡‡‡‡•			•‡‡‡‡‡‡ƒ‡‡‡‡‡‡•
	1 ˆ		1 ˆ
	~‡‡‡‡„‡‡‡‡‡€		~‡‡‡‡„‡‡‡‡‡€
	ˆ Router A ˆ		ˆ Router A ˆ
	•‡‡‡‡ƒ‡‡‡‡‡•		•‡‡‡‡ƒ‡‡‡‡‡•
	1 ˆ IP		1 ˆ IP
	~‡‡‡‡„‡‡‡‡‡€		~‡‡‡‡„‡‡‡‡‡€
	ˆ Router B ˆ		ˆ Router B ˆ
	•‡‡‡‡ƒ‡‡‡‡‡•		•‡‡‡‡ƒ‡‡‡‡‡•
	ˆ		1 ˆ
	1 ˆ		~‡‡‡‡‡‡‡‡„‡‡‡‡‡‡‡‡‡‡‡€
~‡‡‡‡‡„‡‡‡‡‡‡€			~‡‡‡‡„‡‡‡‡‡€	~‡‡‡‡„‡‡‡‡‡€
ˆ Secondary		ˆ	ˆSecondary ˆ	ˆSecondary ˆ
ˆ BSC Device ˆ			ˆBSC Deviceˆ	ˆBSC Deviceˆ
•‡‡‡‡‡‡‡‡‡‡‡‡•			•‡‡‡‡‡‡‡‡‡‡•	•‡‡‡‡‡‡‡‡‡‡•
Point-to-Point			Physical Multipoint
Figure 30. Physical BSC Relay Con®gurations. The numbers in the ®gure represent the group
numbers for BSC Relay.
A virtual multipoint connection connects a single BSC primary and multiple BSC
secondaries by using different BRLY groups (different physical connections).
Figure 31 on page 562			is a diagram of a virtual multipoint con®guration.

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