Internet Protocol Suite Fundamentals; About The Internet Network; Internet Protocol Suite Overview - Acuity Controls nLight ECLYPSE User Manual

Internet Protocol Suite Fundamentals

CHAPTER 2
Internet Protocol Suite Fundamentals
This chapter describes the Internet protocol operating principles necessary to configure the IP parameters of an IP con-
troller.

About the Internet Network

The Internet is the world-wide interconnection of networks. At its root however, it is not one big network, but a group of net-
works that communicate between each other by using standard protocols and by using gateways between these networks
called routers.
The structure of the Internet is decentralized and non-hierarchical. On the Internet, all communication uses the Internet
Protocol (IP) to communicate and all connected devices are identified by their IP address. An Internet Registry allocates IP
addresses to internet service providers to be used by their users.
Data is sent across the network in packets. Each packet has a header that identifies the sender's and intended receiver's
IP addresses.

Internet Protocol Suite Overview

Internet Protocol (IP) is part of a multi-layered suite that together enables data communication. The following descriptions
are an overview of the IP suite protocol layers as used by IP devices:
Physical layer (bits): This is the physical and device-to-device electrical connection layer otherwise known as Ethernet.
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This layer defines:
– The requirements for the physical connection between devices (the signal medium). For example, RJ-45 connec-
tors (attached per TIA/EIA-568-A,), using Cat 5e data cable. The maximum cable length between devices is 328 ft.
(100 m) at 100 MB/s data rate.
– The electrical signal requirements for data packet transport.
– The data packet structure including data payload and the source and destination device's MAC addresses.
In the case of Wi-Fi connected devices, the link layer is the air interface defined by the Wi-Fi standard, such as radio fre-
quencies, data rates, authentication, data channel encryption, and so on.
Data Link layer: This layer implements the ability for two devices to exchange data with each other.
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Network layer: This layer implements the ability to connect multiple distinct networks with each other. It provides the in-
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ternetworking methods that allow data packets to travel from the source device to a destination device across network
boundaries, such as a router through the use of an IP address. See
Transport Layer (segments): This layer provides end-to-end communication data stream connection between two or
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more devices through a variety of protocols. However, it is the Transmission Control Protocol (TCP), the most com-
monly used internet transport protocol that is used by nLight ECLYPSE IP controllers to communicate with each other.
TCP creates a connection-oriented channel between two applications; that is to say the data stream is error-checked,
is sorted into the correct sequence (missing data packets are re-transmitted) and this data stream has a port number
for addressing a specific application at the destination host computer.
Session layer (data): This layer implements the protocol to open, close, and manage a session between applications
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such that a dialog can occur.
Presentation layer: This layer implements the display of media such as images and graphics.
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Applications layer: This layer implements the process-to-process communications protocol that includes among other
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services the BACnet/IP protocol, programming, debugging, WWW, and so on.
All of the above IP suite protocol layers must be fully functional for any two devices or controllers to communicate with
each other.
nLight ECLYPSE
About Routers, Switches, and Hubs.
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