Specifications

UHP-1000 SATELLITE ROUTER
INSTALLATION AND OPERATION MANUAL, V. 2.5
(SW VERSION 2.5.X)
© ROMANTIS 2012 50 www.romantis.com
Actual software release supports acceleration of TCP connections and IP / TCP header compression. Such
functionality allows saving from 1.8% (the maximum size of packets) up to 65% (short packets, e.g. ACKs) of
satellite link throughput. UHP-1000 Satellite Router supports up to 8000 Accelerated TCP sessions simultaneously.
If the limit is exceeded, TCP traffic is passed transparently without any restrictions.
According to laboratory tests, an acceleration of TCP connections allows to reduce web site downloading time by
about 10% and saves about 2% SCPC or TDM bandwidth and up to 20% of TDMA bandwidth.
2.12.1 Configuration of TCP acceleration
The TCP acceleration is available only in TDM/TDMA mini-HUB topology with single Inroute channel, SCPC and in
HUBLESS TDMA topology and uses common configuration command:
tcp acceleration off|on - Acceleration state
TCP protocol includes TCP options exchange between participants of TCP session. In this exchange, the parties
agree on the maximum packet size of session (MTU) and the size of TCP Window. Because the UHP router in
accelerated mode isolates direct exchange between the two parties, such parameters should be set manually on
the router, which will be forwarded to the object initiating a TCP session.
tcp mtu 400-1460 - Advertized MTU
where,
400-1460 size of TCP packet in bytes. Default value– 1460 bytes.
The following command defines TCP Window size:
tcp window 4096-65535 - Advertized TCP window
where
4096-65535 size of TCP Window in bytes. Default value – 65535 bytes.
Actual settings and performance of TCP acceleration can be displayed by command:
show acceleration - TCP acceleration stats
uhp# show acceleration
Acceleration: ON MTU: 1460 Window: 65535
Sessions: 456 Misses: 0 No place: 0 Opt-errs: 0
where,
Acceleration activated/deactivated acceleration
MTU MTU value
Window TCP Window value
Sessions Number of currently accelerated TCP sessions
Misses Packets of sessions which are not represented in the local session table
No place Packets of sessions for which there are no more space in the local session table
Opt-errs Number of packets with TCP options received without respective initialization of session
2.13 Guidelines for actions in the event of faults during preparation
In case of any anomalies of router during its installation and preparation for pointing it is recommended to check
all connections and settings, and then restart the device by pressing the «RESET» on its interface panel by thin
blunt object (e.g. paper clip) or temporarily turn off the power.
If the problem persists restart the unit, a return it to factory settings (see paragraph 4.2) and re-enter the
necessary configuration.
Additional information about the possible faults and workarounds see in paragraph 2.15.4. If the activities
performed do not lead to solve the problem, the device should be repaired at a certified service center.
2.14 Satellite Pointing
Satellite routers have built-in tools for pointing the antenna to the satellite. The router provides actual information
about overall input signal level (RF Level), as well as the quality of the reception of the carrier (C/N) from the Hub
(or carrier of another station in SCPC mode) when demodulators locks on such carrier. Such information can be
obtained in real time via HTTP interface, a local console (command line) or as an analog DC signal.
Pointing procedure is common for any method of displaying the level of signal quality: