Q-Flex Satellite Modem Installation and Operating Handbook
5-2
addresses and static routes can also be entered and displayed in IPv6 format.
TCP acceleration
is supported at up to the maximum data rate for the modem.
Up to 10000 concurrent accelerated TCP connections are supported along with up
to 40,000 unaccelerated TCP connections. Bandwidth utilization when TCP
acceleration is enabled is typically over 90%.
Bridging
,
static routing
and
dynamic routing
(RIP V1 and V2, OSPF V2 and V3 and BGP V4) are all
supported. Ethernet, IP, User Datagram Protocol (UDP) and Real Time Protocol
(RTP)
header compression
are supported. The 14-byte Ethernet frame is
typically compressed to one byte. IP/UDP/RTP headers are typically compressed
to between one and three bytes. The one-way packet processing limit for header
compression is 60,000 packets per second (pps); the two-way limit is 45,000 pps.
IP/UDP/RTP header compression is compliant with the RFC 3095 (Robust Header
Compression) standard.
IP payload compression
is provided (compliant with the
RFC 1951 ‘DEFLATE’ standard). This compresses TCP and UDP packet
payloads by typically 50%.
5.2 Standard-Fit Hardware
5.2.1 IF/L-band Operation
The following are provided as standard:
•
IF operation, via transmit and receive IF BNC connectors (supporting
50
Ω
and
75
Ω
operation at
50 to 90MHz and 100 to 180MHz).
•
L-band operation, via transmit and receive L-band N-type connectors (supporting
50
Ω
operation at
950 to 2150MHz).
•
A high-stability L-band 10MHz reference signal for output to a Block Up Converter
(BUC) or Low-Noise Block (LNB) in order to phase-lock the BUC or LNB’s local
oscillator to a highly stable frequency reference. The 10MHz reference can also
be output through the 50
Ω
BNC station clock connector.
•
A Frequency Shift Keying (FSK) capability for performing FSK communications to
and from a compatible BUC or IF transceiver. This allows remote monitoring and
control of the BUC or transceiver via a modulated FSK signal on the Inter-Facility
Link (IFL) cable.
5.2.2 Ethernet Operation
Two Gigabit Ethernet RJ45 connectors are fitted as standard.
One of these is used for
modem Monitor and Control (M&C) and the other is for satellite traffic. These provide a
combined 150,000 packets-per-second processing capability.
Layer 2 bridging and Layer
3 routing are supported in software.
Trunking mode
is our name for a hardware Layer 2 bridge that supports 160Mbps bi-
directional traffic at up to 500,000 packets per second with zero jitter. Trunking mode
supports ACM (and AUPC) but for all other
XStream
IP™
features, such as compression,
a non-trunking mode must be selected.