Making Things Talk

How to Locate

(Almost) Anything

By now, you’ve got a pretty good sense of how to make things talk to each

other over networks. You’ve learned about packets, sockets, datagrams,

clients, servers, and all sorts of protocols. Now that you know how to talk,

the last two chapters deal with two common questions: where am I,

and who am I talking to? Location technologies and identification tech-

nologies share some important properties. As a result, it’s not uncommon

to confuse the two, and to think that a location technology can be used

to identify a person or an object, and vice versa. These are two different

tasks in the physical world, however, and often in the network environment

as well. Systems for determining physical location aren’t always very

good at determining identity, and identification systems don’t do a good

job of determining precise location. Likewise, knowing who’s talking on

a network doesn’t always help you to know where the speaker is. In the

examples that follow, you’ll see methods for determining location and

identification in both physical and network environments.

8

MAKE: PROJECTS

Address 2007 by Mouna Andraos and Sonali Sridhar

This necklace contains a GPS module. When activated, it displays the distance between the necklace and your

home location. Photo by J. Nordberg.

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