User Manual

Basic Remote Networking Outgoing Connections
4-15
4.6 Outgoing Connections
Note: The SCS does not support outgoing remote node connections.
When the SCS receives a packet, it consults its routing table to determine the best route to the packet’s
destination. If the specified route points to a site, a connection to the site may be initiated. The connection
will be subject to any restrictions defined for the site, such as a startup filter or time of day restrictions.
When a connection to the remote router is initiated, a limited number of packets will be buffered until the
connection is formed. When the connection is successful, the packets will be sent.
Note: To restrict outgoing connections, see Chapter 11, Security.
The SCS can form outgoing connections where it accepts an IP address and a nameserver from the remote
PPP site. Enable this feature with the Set/Define IP IPaddress Dynamic command. Connections which
require these settings include sites which dial up an ISP, where the ISP then assigns the SCS a nameserver
and IP address. For more information, see Dialing Out to an ISP on page 6-5.
To configure the SCS for outgoing connections, you must set up sites. The following sections describe how
the SCS handles these connections.
4.6.1 Ports for Outgoing Connections
Each site must specify which SCS ports may be used for outgoing connections. More than one port may be
specified; for example, site dallas might specify that port 2 or port 3 could be used for outgoing connections.
When the SCS attempts to make a connection to a site, it attempts to use one of the specified ports. If the
port is busy (in use with another connection), it attempts a connection using another specified port. The SCS
uses the port priority setting to determine which ports to try and in what order. In the following example,
site dallas will try port 2 first, then port 3.
Figure 4-23: Port Priority for Sites
If all ports are busy, the SCS will time out the site for a few minutes and then try again. The connection
timeout between call attempts is user configurable. See Define Site Time Failure on page 12-148.
More than one site may specify a particular port. For example, site dallas and site seattle may specify that
port 3 may be used for connections. If site dallas is using port 3 at a certain time and site seattle is started,
seattle will attempt a connection using another specified port. If no other port is specified for site seattle, it
will wait until port 3 becomes available.
Note: To learn how incoming calls use ports and sites, see Starting PPP/Slip for
Incoming Connections on page 4-10.
Local>> DEFINE SITE dallas PORT 2 PRIORITY 1
Local>> DEFINE SITE dallas PORT 3 PRIORITY 2