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Community Member

questions on a very simple Network

usually , a samll network is design as follow:

internet --->cable modem---> Router A----->(LAN)switch --->All pc/internal server.

and there is an additional DMZ link in the Router

A as follow:

Router A----->(DMZ)external web server

I am new to networking and have some simple

questions regarding the above "network " and hope someone helps.

1)In the "network " , the router has a dmz interface and in this

interface, there are web servers for the public. Does all Cisco routers

also can has this interface? do i need to buy some additional

"parts" for the router to has DMZ interface?

2) Normally, service provider will assign a static range of ip to

company, eg. from 61.x.x.1 to 61.x.x.4 (total 4 ip), where

do these ip to be set in the router? set them in the interface of

router that is connect to the WAN?

3) To make the pc in the company can surf internet, does it need

to set nat in the router??

4)normally, the public internet user can surf the company's public

web server by http://61.x.x.1 (the ip assigned statically by

service provider) how to make it possible in the router?

make NAT for it ?

5)if frame relay is provided for the company so that it can

communicate with its branch office somewhere, is it just configure

the frame relay on the router's interface that are connected to WAN ??

6)in router A, how can we assign which interface is for dmz,

which interface is for LAN ?

7)usually, we assign some private ip (eg. 10.1.1.x, 192.168.0.....)

to all interface of router, pc and switch inside LAN.However,I think

the router 's interface that is connected to the WAN could also has

the 4 ip that are assigned from service provider, how to assign these

ip to this interface ?

8)in the network, does Cisco Router has a built-in VPN server, so that

only registered VPN clients in the internet can go into the LAN area

of the Company?

Many thanks



Community Member

Re: questions on a very simple Network


hope these answers will help you

1) Usually Cisco Secure PIX Firewall have the DMZ interface. A third interface on a router is usually reffered as the DMZ interface. I think you need to look into Cisco PIX:

2) Yes, You can configure the WAN port with an IP address that is supplied by your ISP. It could be different in case of Frame relay and it all depends on your custom setup.

3) Since you have only 4 addresses, you will have to cofigure NAT on the router.

4) You will need to configure static NAT for the Web server.

5) Yes, Frame relay will be configured on the WAN interface.

6) Refer to #1 and look at the link provided.

7) One IP address on the WAN interface and most probably use other three for your static and dynamic NAT configuration

8) That is one of the functionality. Refer to the link in #1.

Look at the following link for more Frame Relay information:


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