Network Access While Traveling

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 location

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).