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→Significance of Byte Order
Byte order can introduce ambiguity and complexity when transferring binary data between dissimilar systems; in network protocols and file specifications, it is critical to specify the order of multi-byte values. Some platform-independent remote procedure call (RPC) systems provide functions to ensure that data is always represented "on the wire" in a particular byte order.
Byte order can be significant for performance in some contexts. The 6502 processor, for example, loads the byte following an [[OpcodeOpCode|opcode]] in memory while the opcode is being decoded. Due to little-endian encoding, this byte can be safely assumed to represent bit positions 0-7 regardless of whether the opcode's argument is 1 byte or 2 bytes; if big-endian encoding was used, the first byte read after the opcode might have to be shifted to bit positions 8-15 in the case of a 2-byte argument.
Binary fields in internet protocol (IP) packets are in big-endian order. For this reason, the processors on many routers and other high-speed network devices are big-endian (e.g., MIPS) or run in big-endian order (ARM).