Lexicon PCM92 manual Networking, Subnet Mask 255.255.0.0 Gateway Dhcp Support Enabled

Networking

This section provides a step-by-step guide on how to properly connect the PCM92 to a Local Area Network (LAN) for several different network archi- tectures. The first topology is a simple direct connection using the provided Ethernet cable. The second method describes how to connect and config- ure several PCM92 units to create an isolated network using an Ethernet switch with static or with DHCP. This section concludes with some further networking considerations and troubleshooting tips that will help with con- necting to your PCM92 via Ethernet. If your application is more than these simple examples we recommend that you involve a trained Ethernet network administrator in the design and commissioning of your system.

Careful planning needs be made before placing a PCM92 on a network that provides any access to the public. Some examples of public access are direct access to the unit from the Internet, an unsecured or weakly secured wire- less network, a network jack in a public area that provides network access to the PCM92, or having a computer on the LAN that is not secured so that someone could use it to reconfigure the PCM92. It is highly recommended that the equipment be placed on a protected, isolated network that does not have any connection to the public to prevent unauthorized users from recon- figuring the unit. Please refer to the VPN portion of this section for more information. Factory defaults for the Internet Protocol (IP) settings for the PCM92 are as follows:

Auto-IP/DHCP Address:	169.254.x.x (where “x.x” is determined by
	the PCM92 box numbers)
Subnet Mask:	255.255.0.0
Gateway:	0.0.0.0
DHCP Support:	Enabled

Overview of TCP/IP Basics

IP address

An identifier for a computer or device on a TCP/IP network. Each device in a network has its own IP address to identify it. Example: 126.126.17.42. Networks using the TCP/IP protocol route messages based on the IP address of the destination. An IP address is made of four numbers separated by peri- ods. Each number can be zero to 255. The last number should not be a zero or 255. For example, 126.126.17.1 could be an IP address. 126.126.17.0 would not be a valid IP address. A TCP/ IP or IP address has two parts: the NETWORK ID and the HOST ID. The NETWORK ID identifies the network, and the HOST ID identifies either the subnet and device, or just the device if there is no subnet. The subnet mask is a code that indi- cates which part of the TCP/IP address is the NETWORK ID and which part is the HOST ID. In subnet-mask code, 255 means “This part of the address is the NETWORK ID”. Example: Suppose the IP ADDRESS of

a device is 192.168.xx.yy and the SUBNET MASK is 255.255.x.y. That means, (192.168) is the NETWORK ID. The remaining set of numbers (xx.

yy)is the HOST ID. If your network stands alone (it is not part of a larger network) then the HOST ID identifies each device in the network. If your network is part of a venue’s larger network, your network is actually a sub- network or subnet.

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