Ping, Traceroute, and Whois Help

Ping help

Ping is a network utility that lets you see if another computer can be reached through the Internet. If you are having troubles accessing a particular web page, for example, but not others, you might try pinging it to see if it responds.

Here's what a typical ping session to the popular search engine Yahoo! (www.yahoo.com) might look like:

PING www.yahoo.com (204.71.200.74): 56 data bytes
64 bytes from 204.71.200.74: icmp_seq=0 ttl=251 time=198.7 ms
64 bytes from 204.71.200.74: icmp_seq=1 ttl=251 time=44.9 ms
64 bytes from 204.71.200.74: icmp_seq=2 ttl=251 time=200.5 ms
64 bytes from 204.71.200.74: icmp_seq=3 ttl=251 time=295.7 ms
64 bytes from 204.71.200.74: icmp_seq=4 ttl=251 time=225.8 ms

--- www.yahoo.com ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
round-trip min/avg/max = 44.9/193.1/295.7 ms

It's not as complicated as it looks. Most of the information isn't too interesting unless you're a network engineer. However, the last three lines, the lines that give the 'ping statistics', are pretty useful.

Ping sends 5 small bits of information, called packets, to the other computer, and the other computer tries to send them back. In the case above, all five packets made the round-trip to and from Yahoo! correctly. 5 packets were transmitted to Yahoo!, and all 5 were returned to Northcoast Internet. No packets got lost or destroyed during the trip, so there is 0% packet loss. The final line tells you how fast the packets made the trip, in milliseconds. In our example above, the fastest packet made the trip in 44.9 ms, the slowest in 295.7 ms, and the average speed was 193.1 ms.

If you don't get all the packets back, you might try a traceroute to the same address. Traceroute will give you more specific information on where in the Internet the problem is occuring.

Important: Some large sites (www.microsoft.com, for example) never return ping requests. This doesn't mean anything is necessarily wrong. Try opening the same site in a web browser. If you can open the web page, everything is OK.

Traceroute help

Traceroute is an Internet utility similar to ping. Traceroute not only tells you whether another computer on the Internet is responding, but also the route that information takes from Northcoast Internet's system to that computer.

Here's what a successful traceroute to Humboldt State University (www.humboldt.edu) might look like:

1 core1 (208.25.112.2) 19.045 ms 419.421 ms 3.912 ms
2 sl-gw1-sj-1-4.sprintlink.net (144.228.110.89) 16.537 ms 20.232 ms 21.105 ms
3 sl-bb10-sj-0-2-155M.sprintlink.net (144.232.3.29) 24.060 ms 25.951 ms 36.081 ms
4 sl-bb10-stk-7-0.sprintlink.net (144.232.8.194) 33.928 ms 35.372 ms 21.858 ms
5 sl-bb10-stk-8-0.sprintlink.net (144.232.4.113) 17.691 ms 17.778 ms 19.677 ms
6 sl-gw11-stk-0-0-0.sprintlink.net (144.232.4.82) 43.537 ms 200.254 ms 31.644 ms
7 sl-csuhay-1-0-0-T3.sprintlink.net (144.228.147.14) 29.658 ms 33.550 ms 38.752 ms
8 HUM-HAY-ATM.CSU.net (137.145.202.177) 32.194 ms 45.232 ms 35.632 ms
9 sorrel.humboldt.edu (137.150.148.18) 38.609 ms 36.738 ms 37.167 ms

Each line tells you information about a particular computer on the route between Northcoast Internet's computer sytem and the computer you're tracerouting to.

The first number in the line tells you the number of 'hops', or steps that information takes to reach that computer. Generally speaking, the less 'hops' your information takes to reach its destination, the better. If you can't reach the other computer in 30 hops, traceroute gives up, and it also gives up if you can't reach the site in 60 seconds.

The next bit of information tells you the computer's name and Internet address. The last part of the name tells you what computer network the computer belongs to. For example, in the 7th hop, the computer ends with 'sprintlink.net'. That's part of Sprint's Internet backbone. On the 8th hop, the information is travelling on a different network, CSU.net, which is the California State University system's Internet network. You can find out who's responsible for a particular computer network, like CSU.net or sprintlink.net, using whois.

On the other hand, here's what an unsuccessful traceroute (to a server for the online game Everquest) might look like:

1 core1 (208.25.112.2) 107.191 ms 186.009 ms 19.080 ms
2 sl-gw1-sj-1-4.sprintlink.net (144.228.110.89) 22.962 ms 35.482 ms 20.875 ms
3 sl-bb10-sj-0-2-155M.sprintlink.net (144.232.3.29) 34.581 ms 17.492 ms 21.982 ms
4 sl-bb10-stk-7-0.sprintlink.net (144.232.8.194) 31.373 ms 32.570 ms 20.797 ms
5 sl-bb3-stk-4-0-0.sprintlink.net (144.232.4.14) 21.248 ms 19.631 ms 25.925 ms
6 Hssi8-1-0.BR1.SFO1.ALTER.NET (137.39.166.121) 47.471 ms 43.903 ms 43.296 ms
7 114.ATM2-0.XR2.SFO1.ALTER.NET (146.188.148.222) 70.236 ms 43.396 ms 44.042 ms
8 286.ATM1-0.TR2.SCL1.ALTER.NET (146.188.147.170) 46.267 ms 42.251 ms 44.633 ms
9 107.ATM6-0.TR2.LAX2.ALTER.NET (146.188.137.145) 83.827 ms 82.574 ms 85.921 ms
10 198.ATM7-0.XR2.LAX2.ALTER.NET (146.188.248.133) 298.423 ms 304.531 ms 323.995 ms
11 194.ATM9-0-0.GW1.SDG1.ALTER.NET (146.188.249.69) 334.512 ms 740.838 ms 733.210 ms
12 sonyinteractive-gw.customer.alter.net (157.130.225.134) 287.076 ms 251.620 ms 243.614 ms
13 * * *
14 * * *
15 * * *
Content-type: text/html

Your request exceeded the maximum time limit...

In this example, the traceroute takes longer than 60 seconds, and the traceroute program stops trying to reach it. In a traceroute, the asterisk character (*) indicates a problem. After the 12th hop in our example traceroute, all that's listed are asterisk characters. We can assume that there's a communication problem between the computer listed at hop number 12, sonyinteractive-gw.customer.alter.net, and the next computer on the route to our goal. If we wanted to contact the people responsible for that computer about the problem, we could use whois to find their contact information.

Important: Some remote computers can't be reached with traceroute because they block the special kind of packets traceroute uses. If you can reach the computer with a web browser, however, everything is working properly.

Whois help

Whois lets you see who is responsible for a particular Internet domain. A 'domain' is a name that refers to a computer network owned or controlled by a particular individual, company, or other group. When you look at a web address or computer name, the last two parts of the address are its domain name. For example, Northcoast Internet's web address is www.northcoast.com, and our domain name is northcoast.com. Apple Computer's web address is www.apple.com, so their domain name is apple.com.

Here's what a whois looks like for the domain apple.com:

[rs.internic.net]

Registrant:
Apple Computer, Inc. (APPLE-DOM)
1 Infinite Loop
Cupertino, CA 95014

Domain Name: APPLE.COM

Administrative Contact:
Zimmerman, David Paul (DPZ) dpz@APPLE.COM
+1 (408) 974-2436 (FAX) +1 (408) 974-3103
Technical Contact, Zone Contact:
Eddings, Kenneth (KE557) eddingsk@APPLE.COM
408 974-4286 (FAX) 408 974-3103
Billing Contact:
Zimmerman, David Paul (DPZ) dpz@APPLE.COM
+1 (408) 974-2436 (FAX) +1 (408) 974-3103

Record last updated on 05-May-98.
Record created on 19-Feb-87.
Database last updated on 24-May-99 08:14:43 EDT.

Domain servers in listed order:

NSERVER.APPLE.COM 17.254.0.50
NSERVER2.APPLE.COM 17.254.0.59
NSERVER.EURO.APPLE.COM 194.151.19.41
NSERVER.ASIA.APPLE.COM 203.120.14.5

You agree that you will not reproduce, sell, transfer, or modify any of the data presented in response to your search request, or use of any such data for commercial purpose, without the prior express written permission of Network Solutions.

We can see that the apple.com domain belongs to Apple Computer, Inc., and we can see their mailing address. Whois also lists their administrative, technical, and billing contacts. If you're having a technical problem reaching a computer on Apple's domain, you might try emailing or calling their technical contact about it.