I am wondering if someone could offer a simple configuration for a spare Cisco 2600 router and Cisco 3550 switch combination to allow access to the internet for a small number of future visiting users to a work site. I have looked for information on internet sites but wondered if someone could come up with a simple configuration for router / switch which they have successfully used. I have a temporarily unused 10 Meg optical Ethernet link on site to my ISP who supplied an IP address range (example 123.123.123.160 / 28). My plan was to use one of the ISP supplied addresses on the outside interface and NAT overload on the inside interface using 192.168.1.0 / 24. I am particularly interested in how IP addresses are allocated in the configuration of the external interface to the ISP (i.e. does the ISP use 123.123.123.161 for its end of the link and 123.123.123.162 for the router external interface), the router internal interface to the switch and the switch interface to the router and the switch ports for connection of the client laptops.
On the client laptops I take it the network connection configuration is:
Client IP address ???.???.???.??? ? how are they allocated
Subnet Mask / 24 (255.255.255.0)
Default Gateway Router internal interface IP address
DNS Primary Server Address As supplied by ISP
DNS Secondary Server Address As supplied by ISP
Looking at some internet configurations shown on the router interfaces half duplex is used on the interfaces, is there a particular reason for this ?