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Apollyon
0 pts.
 NAPT?
DataCenter, DHCP, DNS, Networking services
What is Network Address Port Translation? Also, how can I make a log file on my extremely small WLAN showing the MAC and IP of the users and when they logged on and off? Also, I'd like to setup a small DNS server for said network on a small partition on my computer. How would I go about doing that?

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ASKED: January 3, 2005  9:01 PM
UPDATED: January 4, 2005  5:13 PM
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Answer Wiki:
Network address port translation is when a router recieves a request for something eg. a webpage, the router looks at the rquest and sees what address (private) to send requests on that port, in this case 80 to. it is a way to translate public addresses to private addresses without having to buy more IPs
Last Wiki Answer Submitted:  January 3, 2005  9:44 pm  by  Dimpoitc   0 pts.
All Answer Wiki Contributors:  Dimpoitc   0 pts.
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As “dimpoitc” put it, in laymans terms, your router is the key. Your router will take an assigned IP from your ISP and utilize it to send information packs with this IP. Meanwhile on the backend(your side of the network) each of your machines is assigned a private IP by the router utilizing either DHCP or static IP’s. When one of your machines sends a request outside of the network ie..internet, the router utilizes NAT to send that specific machines IP, masks it with its own assigned IP, sends the request out. When the response comes back, the router remebers which internal IP sent the request and relays the information to that said IP. As far as setting up a DNS server, forget it. You have all the tools available to you through your WLAN router. Your router should have the ability to log any and all transactions that you would need to log.

Santoscardenas
 0 pts.
 

You can have two different types of NAT. There’s one to many and one to one NATing. If you have a range of IP addresses from an ISP, you can use one to one NATing to isolate your users from the internet for security. Many to one is when your ISP gives you a limited number of addresses but you have many users that you want to allow on to the internet. In essence, they are sharing one address.

As far as logging MAC addresses and IP addresses, you would need to use SNMP to querry the WLAN device for the information, provided that the device supports SNMP.

As to DNS, I agree that you should not need it locally. Your ISP will provide DNS with the IP address it gives you, if it’s a DHCP assignment. If not, they would have to tell you where their DNS is.

Larrythethird
 0 pts.
 

Could you show me exactly how to set up SNMP, ’cause I think my router supports it. Also, the reason why I want a local DNS is to speed up browsing. Also, what’s port address translation?

Apollyon
 0 pts.
 

What type of Router do you have?

If Cisco Router, from CLI you can simply setup using something like the following (Don’t forget community string else SNMP won’t work)

snmp-server engineID local 0000000000000000000000001
snmp-server community public RO
snmp-server contact Your Network Guru!
snmp-server chassis-id 00000001
snmp-server enable traps snmp authentication warmstart linkdown linkup coldstart
snmp-server enable traps config
snmp-server enable traps entity
snmp-server enable traps fru-ctrl
snmp-server enable traps flash insertion removal
snmp-server enable traps bridge
snmp-server enable traps stpx
snmp-server enable traps rtr
snmp-server enable traps port-security
snmp-server enable traps vtp
snmp-server enable traps vlancreate
snmp-server enable traps vlandelete
snmp-server enable traps MAC-Notification
snmp-server enable traps envmon fan shutdown supply temperature
snmp-server enable traps hsrp
snmp-server enable traps cluster
snmp-server enable traps copy-config
snmp-server enable traps syslog
snmp-server enable traps vlan-membership
snmp-server host 192.168.1.1 syslog

Note that 192.168.1.1 is example of your syslog server, Engine and Chasis Id’s would most likely not be 1, and you don’t have to trap everything… you could be more selective…. but these are just examples.

Having a local DNS server will not speed up browsing, is just used in IP to name resolution… best leave DNS with your ISP as it is easily broken….which will greatly affect your browsing performance by stopping it until DNS repaired.

Dclacy
 0 pts.