827 router newbie question

[mattlucas]

Hi All

Probably a very basic question but as I am new to routers I am going to ask anyway

I have a 827 router and wanted to know how to open up the ports I want. Also is there a way to open all ports ?

[thisisshanky]

If you dont have any ACLs configured, then the router will route packets without any issues. If you have configured NAT on the router and you want to allow connections from the internet to the inside, you can configure NAT static statements for specific ports. Dont know if this is what you are looking for.

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080093f31.shtml

ip nat inside source static tcp

[mattlucas]

I think I am getting a bit confused with the global ip and local ip. Is the global ip the ip address that is assigned by my isp ? if so I do not have a static ip address?? also is the local ip the ip address of my computer that is connected to the router?

Thanks for you help

[thisisshanky]

If you dont have static IP on your wan interface, then each time the ip changes, you will have to change the NAT static command to reflect the new IP, so that outside to inside access can properly work.

I would suggest getting static IP if you need to allow connections inbound. Global IP is the Public IP which is assigned to you by your ISP in this case. Local IP is the IP address of the PC behind the router to which you want connections to be allowed from the outside.

[mattlucas]

Thanks for your reply.

can you not do something like ?

ip nat inside dialer0

i am not sure if the command is formatted corretly but some one has told me you should be able to do something anlong these lines