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Please don't ask me “internal” questions

Every now and then I get a question asking about information that is clearly Cisco-internal, for example:

Hello Ivan!

Can you share some information about this IOS:

  • CallGen - bulk call generator
  • Pagent - Packet Generator

I don't know where to get these images and how to get the License Key for Pagent.

Questions like this should always be directed to your Cisco contacts (try the non-support channels, the always overloaded TAC team usually cannot help you). Even if I had the Cisco-internal information you're looking for, I'm bound by so many Non-Disclosure Agreements that I couldn't share it with you.


  1. "always overloaded TAC" : you just broke the TAC NDA !! :-)

    There are free and open alternatives to our internal tools. Just use scapy instead of pagent/tgn for example.
  2. I never got a documentation marked "confidential" saying TAC is overloaded :))

    Thanks for the Scapy link, looks like a really useful tool. We wanted to use PCs for packet generators in remote labs for quite a while, but somehow never found time to investigate the tools out there. Any idea what a suitable replacement for callgen might be?

    On the negative side, looks like I'll have yet another scripting language to learn. I though PERL, ASP, PHP and Tcl would be enough ... but scapy is written in Python :((
  3. A TCL based packet generation tool is available and is called netexpect. As the name suggests it's basically expect for packets. I.e. you send a packet and expect a response. Unfortunately the wiki is currently down for "repairs" but you can get the source which has examples and documentation from here:
  4. Something that would be VERY interesting would be if someone figured out TCL for it....Then you could run it on any cisco router.
  5. @Anonymous(last): You couldn't generate significant traffic load using Tcl on the router. Furthermore, baseline Tcl (as ported to IOS) supports only TCP sessions, you need host-specific binary libraries to send UDP packets or raw IP packets.
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