
44 CHAPTER TWO
Relevant EPCglobal standards
There are a number of EPCglobal standards that are important to RFID middleware. Two
of these standards are:
Reader protocols
There are efforts underway within EPCglobal to create standards for the reader and
printer network protocols. (We cover reader protocols in Chapter 6.) RFID middleware
vendors plan to support these standard protocols as they become available. We expect
that within the foreseeable future, custom drivers will continue to be required for most
device types.
Application Level Events (ALE)
ALE is an upcoming EPCglobal standard that provides a declarative interface so that
applications can interact with the filtering and collecting engine. The ALE standard sup-
ports request/response and pub/sub-style programming. This approach has proven to be
vastly simpler than the early real-time workflow model of Savant, and it has replaced
all Savant efforts within EPCglobal.
The RFID Service Bus
An enterprise service bus (ESB) is a distributed integration platform designed for applica-
tion connectivity, data transformation, guaranteed transactions, and messaging. An RFID
service bus is a type of ESB used to integrate applications using RFID data. Depending on
the implementation you choose, ESB products offer web services, messaging, business
process orchestration, and other capabilities. Generally, ESBs orchestrate business pro-
cesses across application, ...