Copyright © 2006 – STM Norway AS
Publication no. 101557, Rev. T, November 3
th
, 2006
Page 67
To route unicast/multicast addresses specifically to the GRE interface, use the CLI command
ip
addroute
Example
# ip addroute 225.0.0.2 255.255.255.255 4
will forward multicast datagrams with IP address 225.0.0.2 from the STM SatLink Terminal LAN
interface to the GRE interface .
Forwarding of multicast IP traffic from DVB interface to GRE interface is not supported
in the current release
As shown by the CLI command
ip show -mcast
# ip show -mcast
IP Multicast Routing Table
RouteAddress AddressMask IfIndex
225.0.0.2 255.255.255.255 4
239.255.255.250 255.255.255.255 1
15.3 TCP Performance Enhancing Proxy (PEP)
Conditions particular to satellite communication severely constrict the performance of TCP and reduce
the end users experience of accessing the Internet over satellite. Large latency, elevated bit error rates,
and asymmetric bandwidth are all characteristics of satellite networks that result in degraded TCP
performance. Various TCP Performance Enhancing techniques are used to improve the performance of
the TCP protocol over satellite links. The TCP PEP implementation in the SatLink System makes use of a
TCP Performance Enhancing Server installed in the STM SatLink Gateway and a PEP software client
embedded in the STM SatLink Terminal.
The STM SatLink Terminal embedded PEP client is an optional feature, which is enabled by entering a
license key. Use of the terminal’s embedded PEP client is subject to the Network Operator/ISP supporting
the PEP functionality using a PEP server on the gateway side. It is possible for the Network Operator/ISP
to activate the embedded client software remotely from the gateway, thus requiring no end-user
intervention. Alternatively, an end-user can receive a license key from the Network Operator/ISP and
activate the functionality using the CLI command
sw license
as shown in the example below.
Example:
# sw license pep mykeyforenablingpep
The PEP server in the Gateway may be installed in two different modes.
1.
Re-direct mode
2.
Transparent mode
Re-direct mode is the default setting. The Network Operator/ISP should inform you if the gateway PEP
server is installed in transparent instead of re-direct mode.
When operating in re-direct mode, the IP address of the TCP PEP Server in the gateway must be
configured in the STM SatLink Terminal. If the terminal is authorised to use PEP, this is normally
performed remotely by the SatLink Gateway when the terminal logs on to the network. Alternatively, the
terminal user can locally configure the server address by means of the CLI command
ip pep server
<ipaddr>
using the PEP Server IP address provided by the Network Operator/ISP.