1. Traceroute demonstration
Skills: : use traceroute and query the whois database
Concepts: router hops, whois database
We will use a network utility program called traceroute, to see which routers a packet passes through in moving across the Internet from one computer to another.
We will also see how to query the whois database and review prefixes for small quantities.
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2. Where does this topic fit?
Internet concepts
Applications
Technology (communication)
Implications
Internet skills
Application development
Content creation
User skills
This presentation deals with communication technology.

3. Traceroute
We saw that routers forward packets from network to network as they move across the Internet.
Traceroute lets us see the routers at each hop and we can often identify the network they are associated with.

4. How many hops? How many hops?
How many hops do you think there are between Los Angeles and northern California? Between Los Angeles and Santiago Chile?

5. Traceroute demonstration
Start > Run
Traceroute demonstration – check routes to Google and the University of Chile.
Note that the Windows traceroute client is called tracert.
Note that some networks block traceroute, so you see “request timed out.”

6. Night = Day? Home = School? Same route?
Why does the route vary depending upon when and where you run the test?

7. Whois
OrgName:       California State University OrgId:           CSU-13 Address:         1000 East Victoria St City:            Carson StateProv:      CA PostalCode:    90502 Country:         US RegDate:         Updated:        
Traceroute gives the IP addresses of the routers between two hosts.
You can often identify the organization that owns the router by querying a whois database.
There are many whois lookup services on the Web, like the one shown here, Dnstools.com.

8. For more on this topic, see this teaching module.