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The ultimate aid to teaching and learning Cisco™ Routers

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This software contains NO viruses or spyware!!

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   Version 1.11h   Updated 14 Nov 2007, expires 12/12/2030.

   (Note that the expiry is not an evil plot, it is simply because the product is improving all the time - just come back and get the latest!!)

   Coming up... "acl established" option, EIGRP and OSPF. OSPF NEARLY DONE - REALLY (More complicated than I gave it credit)!!!

   2019: I APOLOGISE FOR NOT UPDATING NETSIMK FOR A LOOOONG WHILE - my life turned REALLY busy, and I hate I can't find the time to update this, I like this project!

   Return regularly to get the latest update.

I am still ok for you to email us any bugs or incorrect functionality, they will be fixed asap!. And if you need a function not yet available, let us know that too!!!

- A few minor bugs in how the route table was populated (ospf).
- Fixed bug when sending msg (eg ping) from a switch (stp could sometimes still block a vlan interface, oops).
- Fixed bug where a big yellow "switch loop warning" was displayed even though the loop was blocked by STP.
- Fixed bug where a new router (or switch !?) would show OSPF interface settings in "show run" (as ospf 99% implemented...)
- Fixed loading of some old file versions. Note that some old file versions may have trouble loading. Please email it to
- Fixed bug where loading old files gave an error.
- Fixed bug where RIP v2 was not handling supernetted ips quite correctly (eg will now be advertised even if rip "network".
- Fixed bug accidently added when dynamic switch trunking added (gave an incorrect encapsulation mismatch).
- Modified routing table construction when dot1q encapsulation exists on subinterfaces.
- Implemented STP commands for cost/priority/portfast.
- Fixed bug where routing protocols were being prevented from passing a NAT interface.
- Implemented "ip classless" and of course "no ip classless" operation.
- Fixed the handling of an incorrect NAT setup, and added a cool "NAT Operation" to the demos in the file menu.
- Fixed first bug due to STP. VLAN interfaces on a switch now cannot be STP blocking.
- Added STP (still to add more stp ios commands).
- Multiple cables between devices (eg console + LAN) now auto separate.
- Bug fix with frame relay packet forwarding when multiple active dlcis on a multipoint interface.
- Temporary release because it expired before STP completed (getting the final topology notification phase working).
- Just for interest, EIGRP and OSPF are next on the list.
- Fixed bug where could not telnet to or from a switches interface vlan.
- Added "Tell me about STP..." in Teaching menu (plus fixed wee bug where simple switch STP never got off listening).
- Fixed bug where DHCP request not forwarded to helper properly when on subinterface.
- Fixed a few bugs in some of the File menu Demonstrations.
- Fixed bug where NAT was not checking statics on some incoming traffic.
- Fixed bug where frame-relay cloud could result in an encapsulation mismatch error.
- Fixed recent bug where outgoing traffic from a loopback had the exit interface IP as source-IP.
- Added default-gateway to switch.
- Beta release of the software with ROAST implemented (native manipulation not yet complete).
- Finished vlan interface+trunking and updated demonstration examples in File menu.
- Fixed some IOS commands that were reporting a syntax error when actaully correct.
- Fixed bug where some commands forced extra parameter entry when not required.
- Added "ip unnumbered".
- Fixed bug where debugging left on, giving arbitrary "out of Range" errors! Sorry about that.
- Fixed bug where copy/pasting a PC gave the new PC the same MAC address as the original, giving obvious problems.
- A PC running a Web Server can now edit the html, or point to an html document. The PC browser is now a 'real' browser.
- Added ability to rename devices in a specific order.
- Added new demonstrations (dhcp relay, route summarisation).

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