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Introduction
When you connect from temporary locations such as a bookstore or
coffeehouse for an hour or two at a time, or when you travel to
a foreign country that may have different power supplies and different
communications standards, there are several special considerations
to keep in mind.
This page provides an overview of the special considerations
and precautions that travelers should take. The complementary Networking
Scenarios provide more particular details about specific situations
such as traveling with a laptop, borrowing
computers at libraries or cafes, connecting
your computer to a home network during breaks and summer vacations, study
abroad,
and more.
Finding out what's available
If you're in a business location that advertises network access,
your best bet is to ask an employee whether the location has any instructions
explaining how to connect to their network. Some common arrangements
include:
- Fee-based or purchase-based network access
Many coffeehouses issue temporary passwords to their patrons in
exchange for either a usage fee or a purchase of coffee or food.
You will likely need to get instructions from an employee and then
visit a web site to enter the password in order to gain access to
the network. Alternatively, many hotels provide Ethernet jacks for
their guests, and network access charges are applied to your bill
just as phone or room service charges would be. Hotels can set their
own rates for network access, so make sure to ask about any fees
before using the network.
If you're not sure whether a business charges for Internet access,
make sure to ask first, and be sure you understand how much they'll
charge for a certain amount of time or bandwidth.
- Dialup access
Nearly all hotels have telephones in every guest room. If you have
a 56K modem, this means that you can probably connect to your dialup
network provider. However, there are several hotel-specific issues
to be aware of:
- Most hotels require you to dial an extra number (commonly
9 or 9 followed by a pause) before you can access a phone line
that can connect outside the hotel itself. Ask a hotel employee
whether extra numbers are required to access an outside phone
line, and then use the advanced
dialup configuration pages and/or the small
hotel scenario to learn how to add the extra number to the
sequence your modem dials.
- Hotels can charge any rate they wish for the use of their
telephone system, over and above any long-distance charges you
may incur. Before you use dialup access from a hotel phone,
make sure you understand what they'll charge you for it.
- Some hotels use digital phone lines rather than analog phone
lines, and connecting to a digital phone line can damage your
modem. Ask to make sure your hotel uses analog phone lines.
- Free, supported wireless network access
Some locations provide unrestricted wireless access to their patrons,
and provide instructions for how to connect to their wireless network.
This type of arrangement is inexpensive and simple to use; however,
because any computer can connect to the network without restriction,
you can run a higher risk of having your computer infected by viruses
or malicious software since there is no security mechanism to block
infected computers from connecting alongside yours. Make sure that
you keep your security systems up to date as described in the laptop-oriented
security
scenarios, and use the campus
VPN server to protect your communication from being overheard.
- Free, unsupported wireless network access
In some locations, employees haven't been trained about the company's
wireless network. In cases like this, you may need to find out what
to do through trial and error. In addition to taking the security
precautions described in the laptop-oriented security
scenarios and using the campus
VPN server, you may need to configure your computer to accept
a DHCP-assigned IP address and connect to a network with a certain
SSID, as explained below.
Configuring your computer to network in a temporary
connection
You may need to make configuration changes to your computer in order
to gain network access to a new location, whether you are using wireless,
Ethernet, or dialup networking.
The three
terms you'll need to be particularly aware of are DHCP, SSID, and
IP address.
Gaining a temporary network identity with DHCP
(for any network)
A DHCP server gives your computer a temporary IP address that identifies
it as a part of the new network. If your computer is configured
so that it uses a single static IP address, it won't be able to
receive the new address it needs to belong to the new network you're
connecting to.
For more information about how to configure your
computer to use DHCP, see the Releasing
and renewing your DHCP-based IP address page.
Joining a wireless network with an SSID (for
wireless networks)
An SSID (also known as ESSID or Network Name) identifies a wireless
network. You may be in an area which receives signals from more than
one wireless network, and so you need to choose which network you'll
connect to. In some places, the SSID you want to use will be obvious;
if you're in a shop called NetCafe and see a network called NetCafe,
that's probably the one you want to choose. In other places, the correct
SSID may not be as obvious. If possible, check with an employee of
the company to determine what the correct SSID is.
Generally, you can click or right-click on the icon that shows your
network connection and select an SSID from the list of available networks.
However, some wireless cards and some operating systems use different
conventions. For more detailed information about changing which SSID
your computer is connecting to, see the instructions that came with
your wireless networking card (or with your computer, if your wireless
card is built in).
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