Lucent Technologies DEFINITY Enterprise Communications Server Release 8.2 Administration For Network Connectivity Manual

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Administration for Network Connectivity
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1  Networking Overview
Valid subnet masksThe valid subnets for each Class of address are:
Notice that all 5 valid Class C subnet masks can also be valid Class B or Class A 
subnet masks, and all 13 valid Class B subnet masks can also be valid Class A subnet 
masks.
For example, 
255.255.255.224 is a valid subnet mask for all three address 
classes. It allows 6 (2
3-2) subnetworks for Class C addresses,...

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Default Gateway
On LANs that connect to other networks or subnetworks, it is convenient to define a 
default gateway node. The default gateway node is usually a router that is connected 
to 2 or more different (sub)networks. It could also be a C-LAN ethernet port that is 
connected to other C-LANs on the same switch. Any packets addressed to a different 
(sub)network, and for...

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1  Networking Overview
When to use IP routes
You need to define IP routes only in special cases when default gateways are not 
defined or when you want to limit communication between nodes. This section 
describes the network configurations that require explicit IP routes.
The following table summarizes when you would use IP routes:
The host and network route types are not specified directly. The system...

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IP Routing ScreenThe following diagram shows the IP Routing screen.
To set up an IP route, enter the node names for the destination and the gateway, and 
enter the slot location of the C-LAN on the local switch. The destination and gateway 
node names and their associated IP addresses must be specified on the Node Names 
screen. 
The Route Type is a display-only field that appears...

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1  Networking Overview
IP Route Examples PPP Connections
The diagram below shows three switches in a DCS network with PPP signaling 
connections between switches A & B and between switches A & C. All nodes in this 
diagram are C-LAN ports. PPP data modules are administered between nodes 1 & 2 
on switches A & B, and between nodes 3 & 4 on switches A & C. With these 
connections, switch A can communicate...

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PPP with Ethernet Connections
The diagram below shows two interconnected (sub)networks. There are three 
switches in a DCS network with a ppp signaling connection between switches A & B 
and an ethernet signaling connection between switch A and the adjunct. Switches A 
& B and the adjunct are on one (sub)network and switch C is on another 
(sub)network. 
Switch A acts as a gateway...

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Administration for Network Connectivity
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1  Networking Overview
The following table shows the IP routes needed if nodes 5 and 6 are not defined as 
default gateways for nodes 2 and 7, respectively.
SwitchNode 
ConnectionsIP Route 
Destination 
NodeIP Route 
Gateway 
NodeComments
A2 —> 7 7 5IP route needed because nodes 2 
& 7 are on different subnets and 
the Gateway Address field for the 
node-2 C-LAN is blank on the IP 
Interfaces screen.
B3...

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Ethernet-only Connections
The diagram below shows three interconnected (sub)networks. There are three 
switches in a DCS network with ethernet signaling connections between them. 
Switches A & B and the adjunct are on one (sub)network and switch C is on another 
(sub)network. Nodes 1, 2, and 6 are C-LAN ports. Node 3 is the adjunct interface port 
to the LAN. Nodes 4, 5, and 7 are...

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Administration for Network Connectivity
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1  Networking Overview
The following table shows the IP routes needed if node 4 is not defined as the 
Gateway Address (on the IP Interfaces screen) for nodes 1, 2, and 3 but node 5 is 
defined as the Gateway Address for node 6.
SwitchNode 
Connec-
tionsIP Route 
Destination 
NodeIP Route 
Gateway 
NodeRoute 
Ty p eComments
A1 —> 6 6 4 hostIP route needed because 
nodes 1 & 6 are on different 
subnets...

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