HD Player
Appendix A: TCP/IP Communications
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Rev. 6.4
Appendix A:
TCP/IP Communications
An Introductory Note
A full explanation of Ethernet communication is beyond the scope of this user guide. However, the following
details should provide enough information to understand the basic concepts.
Ethernet Communication
The HD Player can be controlled via RS-232 and Ethernet connections. Most users will be familiar with RS-232
communication. Ethernet communication, while not a new development, is still a mystery to many.
Let’s compare the differences between RS-232 and Ethernet data:
RS-232
§
Designed for one port to connect to one device
§
Messages transmitted as a whole
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No way to guarantee receipt of data
§
Maximum data transfer speeds of around 115 Kbps
Ethernet
§
Designed to connect many devices (called a “network”) on a single port
§
Messages transmitted in “packets”, as network traffic allows
§
Each device in the network has a unique address, ensuring that a data message goes only to the specified
device
§
Maximum data transfer speeds greater than 100 Mbps
Several types of Ethernet communications exist. The protocol, or language, that the HD Player uses for its
Ethernet communication is called TCP/IP (Transmission Control Protocol and Internet Protocol).
TCP/IP Addressing
Each device on a network requires a unique address to ensure that data is sent only to the device it is intended to
reach. Two methods exist for assigning an Ethernet addresses in a TCP/IP network:
1. Dynamic assignment
2. Static assignment
Dynamic Assignment
Dynamic address assignment requires the use of a DHCP (Dynamic Host Configuration Protocol) Player that
automatically assigns an address to a network device each time it connects. When the device connects, it may be
assigned an address that differs from the address it was last assigned.
