The Packet University

How many times have you been using Wireshark to capture traffic and wanted to narrow down to a range or subnet of IP addresses?  There is an “ip net” capture filter, but nothing similar for a display filter.  Unfortunately, this functionality is often needed after the traffic has been captured.  With a little bit of familiarity with the display filters, this goal can be easily achieved anyway. 

I was introduced to the ASA "VPNSETUP" command by a Matt over on IPExeperts "Online Study List".  Its a different type of command that whan we normally find in Cisco gear.  Basically it allows you to see all of the commands necessary to build a very basic VPN.  If you find yourself in a position where documentation is not readily available, you can output this command to a text file.  Then just tweak it around to your liking and paste it back into the configuration.  Thanks Matt.

Take a look below for the full output of this command.

I have worked in technology full-time for about eleven years. Prior to this, I built PCs and was somewhat of a technical hobbyist. Occasionally, I am faced with the question, “How does one get into computers?” or “How can I get into computer networking?” There are many paths and correct answers to these questions. However, the question that the individual should first ask is the uncomfortable question, “Should, I get into technology?”. The general field of technology can be rewarding both personally and financially. However, it is not a field that everyone is well suited. I would encourage those asking questions about how to get into this field to first make sure that their personal traits fit well with the career choice and that their motivation is not misguided.

Roughly a week ago, The Packet University posed the following question in the form of a poll, "I am pursuing or will likely pursue the following CCIE Track".   I was quite pleased to have 15 CCIE Candidates respond to the poll.  Although this is not a large enough pool of participants to establish a trend, it did give a small sampling of what tracks are being pursued.  Within the poll, the following answers were permitted:

NTP Authentication was introduced in NTP Version 3 with RFC1305.  The reason I placed “Cisco’s Implementation” in parenthesis is due to the fact that RFC did not specify the hashing algorithm that was to be used to compute the hash that is used to verify the NTP message.  Microsoft does not provide authentication using MD5 in the same manner that Cisco does.  In this article, I would like to show two things.  First, I will show how an authenticated NTP Client/Server relationship differs in configuration from a non authenticated client server relationship.  Second, I will provide a look at the packet captures and illustrate how to easily identify Authenticated NTP versus NTP that lacks authentication.