June '03 Tools

What route do your emails and website requests take when they are traveling through cyberspace? It's not a direct one and there can be delays along the way for a variety of reasons.

Did you get my email?

When you send an mail message, it bounces from one server to another on the Internet, often traveling to different countries around the world, until it reaches its recipient.
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The average email message travels through ten to twelve different servers on the Internet before it reaches its final destination. And, the path is never the same; two email messages sent from the same server to the same email address usually travel across complete different paths and across a variable number of servers depending on diverse factors such as the status of the servers at any given time.
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Each stop along the way adds additional time and increases the number of opportunities for error. Emails can experience latency problems ranging from several minutes to several hours. (Assuming that a server did not go down somewhere along the path of the email - which will significantly increase the time and possibility for error).
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Additionally, most companies with computers that process email are protected by some kind of firewall. A firewall's primary job is to act as a gatekeeper between an organization's own machines and the the rest of the world. From the standpoint of another computer trying to deliver mail to a system behind a firewall, what this means is that you can't talk directly to the system; you have to talk to the firewall. This adds yet another bounce in the journey of an email.
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It is estimated that 99% of all email travels over the Internet unsecured leaving a trail on every computer it passes through. At any point along this path your email can be intercepted, copied, stored and read by ISP employees, network administrators or hackers. A recent article reported that 45% of companies are now peeking at employee’s emails.
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How can you find out where your email has been? You can read the header of your email. Here's a great resource for learning about how to read email headers...http://pobox.com/headers.html

Where did that web site go?

One of the first things people often assume when they're unable to reach their websites (or email) is that the server is down. What they don't realize is that there are many other factors that may be causing a disruption of service. There are a couple of easy ways you can find problems with your connections.
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The first way is to use the ping utility provided with most computer operating systems. Ping is used diagnostically to ensure that a host computer you are trying to reach is actually operating. Ping operates by sending a packet to a designated address and waiting for a response. The computer acronym (for Packet Internet or Inter-Network Groper) was contrived to match the submariners' term for the sound of a returned sonar pulse.
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Ping measures the round-trip time in milliseconds for a packet to travel from the computer being tested to a web site and back. Ping loss indicates what percent of the packets sent did not return; ideally this should be zero, indicating that all the packets were returned.
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Reading the results from a ping is simple. The only information you really need to take note of is the time=108.0 ms which tells you how many milliseconds it took for the packet to reach the host and return. There isn't any concern unless these numbers are close to 1000 (one second) or an asterisk "*" appears. If the results do exceed 1000, it may mean that there are some problems with your connection to the Internet, the server's connection, or a connection between you and the server. If an asterisk is displayed, there was no response and that also signifies a problem with the connection between you and the server.
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Ping times and losses can vary greatly depending on the speed and quality of your Internet connection, congestion on the Internet, and the load being handled by the server. In general, ping times under 100ms are typical of T1, DSL, or cable modems. Consistent ping times of more than 500ms should only be seen in connections that span continents (e.g., USA to Europe) and/or are linked by satellite. Ping losses usually indicate Internet congestion.
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The next way is to check connections is the traceroute utility - also provided with most operating systems. Traceroute is a handy tool both for understanding where problems are in the Internet network and for getting a detailed sense of the Internet itself. Traceroute can tell you the path your packets travel as they leave your system and head for their destination. Traceroute can tell you how many routers your packets travel through, how long it takes to travel between routers, and, if the routers have DNS entries, the names of the routers and their network affiliation and geographic location.
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Because several factors may affect a connection at any given time, you may see very different results from repeated tests. To get an accurate picture of how your connection is performing, test several times at once, and at different times of the day. You should also continually monitor your connection across a period of weeks to watch for any ongoing trends or problems.
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When you enter the traceroute command, the utility initiates the sending of a packet, including in the packet a time limit value (known as the "time to live" (TTL) that is designed to be exceeded by the first router that receives it, which will return a Time Exceeded message. This enables traceroute to determine the time required for the hop to the first router. Increasing the time limit value, it resends the packet so that it will reach the second router in the path to the destination, which returns another Time Exceeded message, and so forth. Traceroute determines when the packet has reached the destination by including a port number that is outside the normal range. When it's received, a Port Unreachable message is returned, enabling traceroute to measure the time length of the final hop.
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Each hop in the route that the packet has traveled will be displayed in order with the hostname and/or IP address. Next, the results, in milliseconds, of the three probes that are sent to each hop. The rules for ping results also apply here. Numbers near 1000 and asterisks represent network problems. Each hop is measured three times. (If you see an asterisk (*), this indicates a hop that exceeded some limit.)
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On computers running Windows, ping and tracerout can be accessed via the DOS prompt. Select "Run..." from the Start menu and type "command". Or, you can click on the MS-DOS Prompt shortcut in your Start Menu. Once you're at the DOS prompt, type the command ping followed by the URL you want to ping, or the command tracert followed by the URL you want to trace, For example, to ping Google, type ping www.google.com. To traceroute Google, type tracert www.google.com.