Cisco Cisco Packet Data Gateway (PDG) Documentation Roadmaps
New In This 8.0 Release
▀ GGSN Features
▄ Cisco ASR 5000 Series Product Overview
OL-22937-01
When storing CDR files on the SMC hard disk, first they are stored on RAMFS before they are moved to the hard disk
and then they can be off-loaded via ftp or sftp to an external server (such as the L-ESS or the GSS) or billing system.
For additional support information, see .
and then they can be off-loaded via ftp or sftp to an external server (such as the L-ESS or the GSS) or billing system.
For additional support information, see .
Use the new command
command in
GTPP Group Configuration Mode to configure and enable hard disk usage.
Use the new show/clear commands
in the Exec Mode to monitor/clear the file counters and statistics on the hard
disk.
Use the new
and
commands in the Global
Configuration Mode to allocate RAM for files and the number of compression process to support the hard disk
functionality.
functionality.
GRE Protocol Interface
Benefits
GRE protocol functionality adds one additional protocol the ASR 5000 to support mobile users to connect to their
enterprise networks through Generic Routing Encapsulation (GRE).
enterprise networks through Generic Routing Encapsulation (GRE).
GRE tunnels can be used by the enterprise customers of a carrier 1) To transport AAA packets corresponding to an APN
over a GRE tunnel to the corporate AAA servers and, 2) To transport the enterprise subscriber packets over the GRE
tunnel to the corporation gateway.
over a GRE tunnel to the corporate AAA servers and, 2) To transport the enterprise subscriber packets over the GRE
tunnel to the corporation gateway.
The corporate servers may have private IP addresses and hence the addresses belonging to different enterprises may be
overlapping. Each enterprise needs to be in a unique virtual routing domain, known as VRF. To differentiate the tunnels
between same set of local and remote ends, GRE Key will be used as a differentiator.
overlapping. Each enterprise needs to be in a unique virtual routing domain, known as VRF. To differentiate the tunnels
between same set of local and remote ends, GRE Key will be used as a differentiator.
Description
GRE Tunneling is a common technique to enable multi-protocol local networks over a single-protocol backbone, to
connect non-contiguous networks and allow virtual private networks across WANs. This mechanism encapsulates data
packets from one protocol inside a different protocol and transports the data packets unchanged across a foreign
network. It is important to note that GRE tunneling does not provide security to the encapsulated protocol, as there is no
encryption involved (like IPSEC offers, for example).
connect non-contiguous networks and allow virtual private networks across WANs. This mechanism encapsulates data
packets from one protocol inside a different protocol and transports the data packets unchanged across a foreign
network. It is important to note that GRE tunneling does not provide security to the encapsulated protocol, as there is no
encryption involved (like IPSEC offers, for example).
GRE Tunneling consists of three main components:
Passenger protocol-protocol being encapsulated. For example: CLNS, IPv4 and IPv6.
Carrier protocol-protocol that does the encapsulating. For example: GRE, IP-in-IP, L2TP, MPLS and IPSEC.
Transport protocol-protocol used to carry the encapsulated protocol. The main transport protocol is IP.
The most simplified form of the deployment scenario is shown in the following figure, in which GGSN has two APNs
talking to two corporate networks over GRE tunnels.
talking to two corporate networks over GRE tunnels.