ADTRAN Express 5210, User Manual

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61200208L1-1 Express 5210 User Manual 5-1
Chapter 5
Applications
This chapter provides examples of some common Express 5210
data and voice applications. The data examples include SNA/
SDLC with local spoofing, transparent, and LAN applications. The
voice applications (which begin on page 5-9) include switched,
daisy-chaining, PLAR circuits, and direct FXS/FXO. The
configuration selections given in these examples may need
modification based on your network configuration.
DATA APPLICATIONS
SNA/SDLC with Local Spoofing
When used in an SNA/SDLC network, the Express 5210 provides
local spoofing by emulating the primary or secondary SDLC roles
(see Figure 5-1). The Express 5210 performs conversion from SDLC
to frame relay and also terminates SDLC links, providing primary
and secondary emulation between Express 5210s. Local spoofing
improves performance by reducing traffic across the frame relay
network and allows definite response times on the SDLC links.
To perform spoofing, the Express 5210 automatically sets itself up
to provide primary or secondary emulation based on the receipt of
SNRM (set normal response mode) from an SDLC device. The
Express 5210 looks for SNRM on all ports and assumes a secondary
role once SNRM is received. The Express 5210 then brings up the
LLC2 link across the frame relay network to another FRAD which
assumes a primary role. This allows the Express 5210 to operate
with PU 2.1 devices.