User Manual

Message Routing and Migration
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Boomer II User Manual & Integrator’s Guide
Wavenet Technology 92 BM210012WT09
ASCII versus Binary Encoding
DataTAC 4000 system SCR fields are all ASCII encoded fields of
numeric values or alphanumeric strings. DataTAC 5000 and 6000
systems use a mixture of ASCII and binary encoded fields. All three
systems allow the user to send binary data, regardless of header
encoding.
Support for TCP/IP
DataTAC 5000 systems provide support for TCP/IP hosts, allowing
interconnection across local Ethernet LANs or even the Internet. SCR
messages are carried within a single TCP/IP data stream, which allows
SCR communications with multiple terminals.
Although TCP/IP provides a reliable stream of contiguous data, the
application must be able to determine the beginning and end of each
SCR message. The SCR header on DataTAC 5000 systems must start
with a 16 bit (2 byte) length field (bytes L1 and L2), which specifies
the length of the frame.
Length Prefix Field
DataTAC 5000 systems require all SCR messages to be prefixed by a
two-byte binary encoded length field (L1 and L2). This field provides
TCP/IP based connections with data that determines the length of each
SCR message. The length count includes everything in the message
packet, except for the length prefix.
When converting an application to a DataTAC 5000 network, the
length field must be prefixed to all SCR messages.
Host Authentication
Before SCR transactions can be performed on DataTAC 5000 and
DataTAC 6000 systems using a host-initiated connection, the host first
sends a host authentication message to the radio network gateway
(RNG). The authentication message must be the first message sent to
the RNG after establishing link layer communications. The RNG drops
the connection when any of the following conditions occurs:
q The host does not send the authentication message within one
minute
q The host ID and password do not match those in the RNG
database
q The host is not enabled in the RNG database
q The host is already connected to the RNG
On DataTAC 5000 systems the authentication message consists of:
q Host ID (up to 20 characters)
q ASCII ‘;’ (semicolon) delimiter
q Host password of 1 to 8 bytes
q Carriage return