How A Packet Returns To The Remote Node - Bay Networks Baystream 7 Configuration And Troubleshooting Manual

Configuring and Troubleshooting Bay Dial VPN Services
4.
5.

How a Packet Returns to the Remote Node

To send packets from the home network to a remote node, Dial VPN essentially
reverses the process described in the previous section. The tunnel ensures that
packets from the corporate home network reach the remote node, regardless of
where it is located. The Dial VPN gateway is responsible for intercepting and
forwarding packets to the remote node using a care-of address that is specified to
the gateway during the connection process. This address, which is usually the
address of the Dial VPN Remote Annex, is the IP address of the other endpoint of
the tunnel. When the gateway encapsulates the frame relay packet into a GRE
packet, it includes the care-of address.
Figure 2-5
network to a user at a remote node through an erpcd-based network.
2-16
The frame relay packet contains flag fields to indicate the beginning and end
of a frame; an address field to indicate a logical point that defines the data link
between the gateway and the home network and the terminal endpoint
identifier; a control field to indicate the type of frame; an information field
that contains the data to set up the link; a cyclical-redundancy check field; and
the original data from the data packet. Refer to the BayStream manuals for the
type of link you are configuring (Configuring Frame Relay Switching Services
or Configuring Frame Relay Services for IP Routing) for more information
about the frame relay packet.
The gateway sends the frame relay packet to the CPE router on the
corporate home network.
The CPE router decapsulates the frame relay information and routes the
data to the intended recipient on the home network.
shows a simplified view of how a data packet moves from the home
BayStream Multiservice Software Version 7.2 115623B Rev. 00