Network Connections and Topologies | 3Com PLM Series, NCG-PLM

5 Network Connections and Topologies

5.1PLM Series Network Cabling

The common cable categories used for high band- width network connectivity are Cat-5e and Cat-6; these are preferred choices for PLM Series network use. However, Cat-5 may be used in limited applica- tions, as explained below.

Cat-6, as the designation implies, is the newer standard, and it is designed to accommodate high- speed networks up to 250 MHz. The 10000BASE-TX standard (using 2 pairs) requires Cat-6 cabling. Cat-6 is fully compatible with all PLM Series network applica- tions (including use with Dante) as it accommodates all current Ethernet protocols.

Cat-5e (using 4 pairs) supports 1000BASE-T ap- plications, and is also fully suited to all PLM Series applications, including Dante.

Cat-5 cabling meets the requirements for the PLM Ethernet control network. However, the higher ratings of Cat-5e and Cat-6 are recommended for use as the backbone between switches, particularly if Dante is being used.

Cat-3 or Cat-4 cables may still be in use in some installations. Neither of these satisfies the bandwidth requirements of 100BASE-TX or 1000BASE-T net- working, and should not be used with PLM Series networks.

Table 5.1 can be used as a guide when specifying maximum recommended lengths for Ethernet cables within a PLM network:

	Spectral
	Bandwidth	Max Length	LAN
	100 MHz	100 m	100BASE-TX
Cat-5	100 MHz	100 m	100BASE-TX
			100BASE-TX
			100BASE-TX
Cat-5e	100 MHz	100 m	1000BASE-T
	250 MHz	100 m	1000BASE-TX
Cat-6	250 MHz	100 m	1000BASE-TX

Table 5.1: Recommended PLM network cable lengths

5.2PLM Series Topology Overview

Thanks to the auto-sense and auto-uplink features of the PLM Series’ Ethernet ports, connecting multiple units is a simple task. A free-topology network can be implemented easily, including external switches or hubs as required.

Following are some examples of various network configurations that can be used when setting up a PLM network.

5.2.1 Daisy-chained devices

If a daisy chain network system (see figure 3) is implemented, the secondary Ethernet connectors on PLM Series devices can be used as “loop-thru outputs” to send the audio and/or control signal to the next unit in the chain (i.e. in the same rack). As an example, a system utilizing a Dolby Lake Processor as a “break in point” would find the DLP typically connected to the Primary Ethernet port of the first PLM in the rack. The signal would then travel from the Secondary Ethernet connector of this PLM Series unit to the Primary Ethernet connector of the next unit in the system, and so on.

Care must be exercised in implementing a chain topology network, as the number of PLM Series devices being connected in this way will have a critical bearing on network

performance parameters such as overall latency. Also, the use of single layer cabling to connect the network will introduce the possibility of Single Point of Failure issues, which should be avoided at all costs when operating critical systems Therefore, this top- ology is NOT recommended at all for applications using Dante and it is NOT recommended for applica- tions with more than 10 PLMs, even when not using Dante.

100
	100		100
	100		100


		100


	100		100

Figure 5.2.1: Daisy chain network topology

8PLM Series Network Configuration Guide

NCG-PLM, PLM Series specifications

The 3Com NCG-PLM, PLM Series is a notable product line from 3Com Corporation designed to enhance network management and provide a robust infrastructure for businesses. This series is centered around providing seamless connectivity and efficient network performance while supporting a variety of applications and services.

One of the main features of the PLM Series is its advanced network management capabilities. The series offers a comprehensive suite of management tools that facilitate easy monitoring and configuration of network devices. This enables IT administrators to gain visibility into network performance, troubleshoot issues, and manage bandwidth effectively. The user-friendly interface simplifies these processes, allowing for quick adjustments and ensuring optimal functionality.

The PLM Series integrates cutting-edge technologies to support high-speed connectivity and data transfer. With support for Gigabit Ethernet, the series ensures that data can be transferred rapidly across networks, meeting the growing demands of modern applications and user expectations. Such speed is crucial for businesses that rely on data-intensive applications, video conferencing, and cloud services.

Furthermore, one of the hallmark characteristics of the 3Com NCG-PLM Series is its reliability and scalability. Designed to accommodate increasing network demands, the devices within this series can easily expand to support additional users and devices. This scalability ensures that organizations can grow without the need for extensive overhauls of their existing infrastructure.

Security is another paramount feature of the PLM Series. It employs various security protocols to protect sensitive data and maintain the integrity of the network. This includes measures against unauthorized access, ensuring that only authenticated devices and users can connect to the network. This commitment to security is critical in today’s climate where cyber threats are ever-evolving.

The PLM Series is also designed with energy efficiency in mind. The devices consume less power without compromising performance, thereby supporting sustainability initiatives within organizations. This energy-efficient design can result in significant cost savings on power consumption over time.

In summary, the 3Com NCG-PLM, PLM Series stands out for its advanced network management tools, high-speed connectivity, reliability, scalability, strong security measures, and energy efficiency. These attributes make it an ideal choice for businesses seeking to optimize their network infrastructure and cope with the increasing demands of modern digital operations.