failure of the master machine, another machine designated as a backup master can take over the function of master machine. Also, since machines within a single domain can be of different architectures (x86, IA32, SPARC, P-Series, etc.), the Bridge is also responsible for handling differences in things like endianness. On Oracle Exalogic Tuxedo leverages the RDMA capabilities of InfiniBand to bypass the bridge. This allows the client of a service on one machine to directly make a request of a server on another machine. Flexible buffer formats Tuxedo applications can utilize a variety of message formats depending upon the type of data that is to be passed. One of the most popular formats is the FML buffer format which is much like a binary XML or ASN.1 format. FML buffers can contain an arbitrary number of named fields of arbitrary type. Fields can be repeated and nested. As it is a self-describing binary format, the processing of fields incurs very little overhead in comparison to the parsing necessary to support something like XML. VIEW buffers are essentially records, C structures, or COBOL copybooks. A VIEW buffer has an external description which allows Tuxedo to access the fields within it if necessary for things like data dependent routing. Other buffer formats include XML, CARRAY (opaque binary data), STRING, and MBSTRING (a string buffer containing multibyte characters.) Tuxedo can automatically and transparently convert FML buffers to and from XML buffers. There is also support for user-developed buffer types (for example JamFlex buffers defined by Tuxedo version of Panther RAD toolset). Communication concentrators For remote clients (Java, CORBA, or/WS), Tuxedo provides communication concentrators called listener/handlers that handle the remote network communication. Clients connect to these communication concentrators, which act as proxies for the clients. As clients make requests, the listener/handler uses the local Tuxedo infrastructure to make the request on the behalf of the client. Tuxedo then load balances the requests across the servers within the domain that offer the service even if the server is not on the local machine. This is in contrast to most Java EE application servers where load balancing is done by the client making requests to different machines with the cluster. Gateways To facilitate the sharing of services across domains, Tuxedo provides domain gateways. A domain gateway allows importing and exporting services from remote domains. This allows the local domain to see services on remote domains as