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Q1. How does broadband internet
services over a satellite link work?
Q2. What are TCP acceleration and spoofing
and why is it important?
Q3.
How important is the FastZONE UDgateway® at
the customer premises and what does it do?
Q4. There are a number of providers of
IP services by satellite, what makes FastXONE unique?
Q5. Are there any advantages to a satellite
service over other broadband services?
Q6. The satellite service seems quite expensive
when compared to DSL offerings?
Q7. Is the number of PCs that can be connected
under a single subscription limited?
Q8. Is there any restriction or limitation
on usage?
Q9. Can I change my subscription package?
Q10. How will I be billed for my Services?
Q11. How will I be billed if I subscribe
in the middle of a calendar month?
Q12. Can I terminate
my subscription?
Q13. Is the bandwidth
specified for the service
guaranteed?
Q14. What equipment do I need to obtain
the service?
Q15. Must I purchase the satellite equipment
to obtain the service?
Q16. The FastZONE™ system is based on
an international standard – does this mean that the
terminal that you are marketing can be used in conjunction
with other operators’ services?
Q17. Do I need any special equipment to
use voice services on the FastZONE network?
Q18. What is all this talk about TCP
windows to adapt PCs to high-bandwidth transmissions?
Q19. Are their any technical limitations
to the FastZONE™ service?
Q20. Does this latency
affect any other aspect
of the service?
Q21. How does Fastnet Broadband deal with
the latency issue?
Q22. Does this latency
problem affect VPN services,
and how does Fastnet
deal with this? 
Q1. How does broadband
internet services
over a satellite
link work? 
A1. The FastZONE™ service
uses a satellite connection as a high-speed digital link between
a customer’s location
and the worldwide Internet backbone. The data travels from
the satellite antenna at the customer’s location to the
satellite, and then to the teleport in Monaco for routing to
the Internet.
The teleport is a secure facility where many large aperture
satellite dishes are operated. At the teleport, routers are
redundantly connected to the Internet using OC-3 optical connections
to several Tier-I Internet backbone providers.
Proprietary acceleration and advanced spoofing technology
is employed both at the customer premises and at the teleport
to provide IP transparency and increase throughput speed.
Q2. What are TCP acceleration and spoofing
and why is it important?
A2. The entire Internet is based
on TCP/IP. TCP (Transmission Control Protocol), which manages
and controls transmissions
using IP (Internet Protocol). TCP sends data and looks for
acknowledgments (receipts) sent back from the receiving end
to indicate that everything was received. If the acknowledgments
are not received, TCP resends the packets and slows down its
transmission speed for future data. TCP expects these acknowledgments
to be received within a certain time frame. Because of the
long round-trip (90,000+ miles) that the packets must travel
over the satellite link and back, the acknowledgments are delayed
by several hundred milliseconds. If uncorrected, this delay
would cause TCP to throttle back its speed dramatically.
Spoofing is accomplished by special equipment that causes
TCP acknowledgments to be returned to the sender very quickly.
It does this by spoofing (pretending to be the remote site)
and acknowledging the packets instantly, at the same time as
it forwards the packets to the remote site. TCP sees rapid
acknowledgments and therefore ramps up its speed quickly. The
Gateway also looks for the real acknowledgments and discards
them. If an acknowledgment is missed, the Hybrid Gateway resends
the packet from its buffer. It is in this manner that multi-megabit
speeds are made possible over satellite.
Q3. How important is the FastZONE UDgateway® at
the customer premises and what does it do?
A3. The FastZONE UDgateway® significantly
enhances the performance of our business services. It sits
between the indoor
unit (the satellite modem/router) and the local area network,
and handles all Internet access traffic coming from the corporate
site. It is the first all-in-one appliance that is specifically
adapted to broadband satellite-delivered Internet access. All
IP key features such as addressing and routing, security, caching
are embedded in the appliance along with performance enhancement
technology. including TCP acceleration, QoS-based differentiation,
HTTP pre-fetching, as well as web and DNS caching. It is designed
to be easily installed, configuration is done via a web-based
interface. A wizard automates the setup process, requiring
the input of just a few parameters.
Q4. There are a number
of providers of IP services by satellite, what makes FastZONE
unique?
A4. The Fastnet service has several
unique advantages over competitive services.
First, it is provided in partnership with one of the world’s most sophisticated
telecommunications companies and the leading provider of satellite broadband
services in Europe.
Second, our proprietary gateway technology significantly enhances
the quality of the FastXONE™ service, both in speed and
reliability, and through the use of QoS, facilitates the provision
of voice and video services as well as IP data.
Third, our tier one carrier to carrier interconnection arrangements
to the world’s communications networks assure rapid access
to the Internet and low cost, carrier quality, voice termination.
Fourth, no other provider of satellite broadband services
offers an integrated voice services package.
Fifth, no other provider of satellite broadband service offers
a tried and tested, fully integrated wireless conection.
Q5. Are there any advantages to a satellite
service over other broadband services?
A5. Yes, there are several. First
and foremost, satellite services are available everywhere,
where as other broadband services
are available only in limited locations. Secondly, satellite
services do not require any other communications or telephone
connection. Thirdly, the FastZONE™ satellite services
are future proof, services can be expanded exponentially using
the same equipment (in our case up to 10Mbs), allowing easy
expansion of services to meet growing user needs.
Q6. The satellite service seems quite expensive
when compared to DSL offerings?
A6. Yes, at first glance, the
satellite service does appear to be more expensive, however,
on closer comparison the satellite
service is not that much more expensive then the equivalent
DSL service, and is considerably less expensive than other
broadband alternatives such as ISDN or leased lines. Moreover,
Fastnet offers a range of community services where a number
of smaller users share a satellite connection. This shared
use services reduces the cost of a broadband connection to
less than the most competitive DSL offerings.
Q7. Is the number of PCs that can be connected
under a single subscription limited?
A7. Absolutely not! You can link
up as many terminals as you wish. The numbers indicated are
for information only, a guideline
to ensure a reasonable quality bandwidth. We have tested these
services with the recommended number of computers and have
found that this number of users can be connected to the network
simultaneously with no degradation of service. If you connect
any more terminals, the quality of the data connection will
possibly decrease.
Q8. Is there any restriction or limitation
on usage?
A8. No. You may send as much
traffic over the system as you desire. There are no limits
or restrictions on usage.
Q9. Can I change my subscription package?
A9. Yes, you may change your
subscription package at any time. Any change becomes effective
from the first day of the following
month.
Q10. How will I be billed
for my Services?
A10. Services are billed on a
subscription basis, monthly, in advance.
Q11. How will I be billed if I subscribe in
the middle of a calendar month?
A11. The principle is as follows:
For orders placed between the 1st and 9th day of the month, you will be billed
for 2/3 of that month.
For orders placed between the 10th and 19th day of the month, you will be billed
for 1/3 of that month.
For orders placed between the 20th and the end of the month, you will not be
billed since your account will only be opened on the 1st day of the following
month.
Q12. Can I terminate my subscription?
A12. You can terminate your subscription
at any time. However, upon termination we will impose a termination
charge which
will be based upon the length of your use and the amount of
time remaining on your contract. In addition, if you are renting
the equipment, we will charge a removal fee.
Q13. Is the bandwidth specified for the service
guaranteed?
A13. No, that figure is an indication
of the maximum bandwidth that you may reach from time to time.
The average bandwidth
will vary, but can generally be expected to be around 50 to
70% of that figure.
Q14. What equipment do I need to obtain the
service?
A14. The service requires a satellite
dish, which may be attached to a rooftop or to building walls,
a satellite modem/router,
and for business services, a UD Gateway device. This equipment
connects on a plug-and-play basis to either a wireless or wired
local area network, or directly to one or more computers via
a network hub. Axis provides all of the necessary equipment,
and assures its efficient installation.
Q15. Must I purchase the satellite equipment
to obtain the service?
A15. No, we also offer a low
cost monthly rental plan for the satellite equipment.
Q16. The FastZONE™ system is based
on an international standard – does this mean that the
terminal that you are marketing can be used in conjunction
with other
operators’ services?
A16. Yes. The DVB-RCS standard
has been adopted by other manufacturers and operators and is
in the process of being adopted throughout
the world for bi-directional satellite transmission systems.
For the client, this is a guarantee of compatibility with other
suppliers of DVB-RCS compatible products and services.
Q17. Do I need any special equipment to use
voice services on the FastZONE network?
A17. No, you can use our basic
voice services over a regular computer connection, providing
that the computer used has a
microphone
and speaker. However, a number of manufactures now make IP
telephones, and interface devices to connect standard telephone
systems to IP networks. For our carrier grade service a small
interface device is required between the FastZONE Gateway and
the telephone system. We provide this device at no charge.
Q18. What is all this talk about TCP windows to
adapt PCs to high-bandwidth transmissions?
A18. The size of the TCP window
corresponds to the maximum number of packets that can be sent
without waiting for a positive
acknowledgement receipt. Larger TCP windows tend to improve
the performance of TCP/IP when large quantities of data are
transmitted in a high-bandwidth environment. PCs running Windows
95, 98 and NT do not support large TCP windows in native mode.
Q19. Are their any technical limitations
to the FastZONE service?
A19. Yes, firstly, to install
the satellite station the site must “see” the
equator at 10% southeast. Secondly, because of the distances
inherent in satellite communications (approx 44,000 Km to and
from the satellite) there is an issue of “latency” in
satellite services. This means that since communications to
and from the satellite travel at the speed of light, that a
complete two transmission via satellite will take 350 milliseconds
(.350 seconds). As a result of this latency, satellite systems
are not suitable for uses which require simultaneous data transactions,
such as real time, on-line gaming.
Q20. Does this latency affect any other aspect
of the service?
A20. Due to the characteristics
of IP networks, excessive latency can cause networks to operate
slowly. We have surmounted that
problem by clever engineering, and the latency inherent in
satellite services should not be apparent to most users. Indeed
most users find that the service operates with greater speed
and more efficiently than an equivalent DSL connection.
Q21. How does Fastnet Broadband deal with
the latency issue?
A21. To understand how Fastnet
works around the latency issues created by the satellite service,
it is important to understand
the
issue. TCP/IP is the “language” of the Internet.
It works by sending packets of data, and then waiting for acknowledgments
of receipt. These acknowledgments signal the sender to transmit
more data. When acknowledgments return slowly, TCP then slows
the speed at which data is being sent in order to avoid overloading
a network that it assumes is already congested.
TCP works by starting a TCP/IP session slowly. Speed builds
as the networks capacity to carry traffic is verified by the
rate of the acknowledgments. This effect is known as slow-start.
Since TCP was designed for terrestrial networks that have
less latency than a satellite network, the longer satellite
latency (400-600ms range) will cause TCP to expect an acknowledgment
before the round trip to the remote site can be completed.
Because TCP was originally designed for low-latency terrestrial
networks, it does not understand that a satellite is involved
and operates as if the satellite latency was caused by congestion.
If uncorrected, this effect causes all packets over a satellite
network to be sent at the slow-start rate.
In the Fastnet service TCP/IP acceleration compensates for
the space-link transit time. TCP acceleration is accomplished
by special equipment at the main satellite hub site, and on
our corporate services, at the customer’s premises.
This equipment appears to TCP as if it were the remote location,
while acting as a relay or forwarder for data packets going
to and from the remote satellite location. When the equipment
receives Internet traffic destined for a remote satellite location,
it acknowledges receipt of the packet immediately on behalf
of the remote site so that more data packets will follow immediately.
In this manner, the latency is “hidden” because
the acknowledgments are returned rapidly. As a result, TCP
moves out of slow-start mode quickly and builds to the highest
possible speed.
The equipment also watches for real acknowledgements coming
back from the remote site and suppresses them. If the acknowledgement
is not received from the remote site, the system automatically
re-sends the packet from its buffer. Thus, satellite-connected
sites communicate seamlessly with servers on the terrestrial
Internet.
Q22. Does this latency problem affect VPN
services, and how does Fastnet deal with this?
A22. In a VPN-over-satellite
session, the packets are encrypted and, therefore, can only
be acknowledged
by the actual VPN
client software at the remote site – not by the acceleration
equipment. Acceleration is bypassed. Consequently, acknowledgments
are delayed and the slow-start data rate remains in place during
the entire session. This results in substantial performance
degradation. Traditional VPN over satellite may be faster than
dial-up, but is not a robust multi-user broadband experience.
The FastZONE solution
creates an encrypted private satellite network, a hybrid VPN
and PN (Private Network) between the
remote satellite
location(s) and then securely connects this satellite network
directly to the customers network via our remote UD Gateway
device. As a result it does not have the VPN-over-satellite
performance limitations.
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