Structuring the network services - A simple start

As a network administrator, we keep our network growing and up all the time. But, some decisions which we have taken early, becomes a mess and creates many issues now. Yes the one of the issues well known for most of the administrators are the IP assigning.

One of the network started with 4 computers, later became 2 servers and 10 stations, later increased and became more than 50. The computers were not fixed in same place, they started moving between departments, a new one started to get added every week, while new laptop users jumped on and off. 3rd party providers came to office and started working for some time and they were, on and off.

The static IPs were split into zones and assigned but later the tracks were not right.. The PC entry log(at the gates) said we have more than 200 visitors every 3 months. Where our sub-net supports only 255 computer!!!!!!

Yes the answer is simple, we need a DHCP.... but we also needed proper network structure.
We need to know the network usage properly. We have wireless users and wired network users.
All wireless users are laptop users, while few laptops connect through the wired network.

The first level of separation is wired users and wireless users. Our internet gateway server has 2 Network cards which connects to internet and wired network, while the wired and network and wireless are mixed through the hubs.

Now a new NIC card is added in the gateway server and that is used to connect to the wireless hub. A DHCP is used to assign range of IPs for wired network (192.168.1.51 - 150). While the gateway server for wireless network is the same gateway server, but it uses different network address range in 192.168.2.x, A DHCP for this zone is enabled and the IP is leased from 192.168.2.51 to 192.168.2.100.

Now the network has few servers where they belong to wired networks... their IPs are added to static range from 192.168.1.2 to 192.168.1.50.

The gateway server now has a firewall / routing rule. Only few mac address of the wireless network are allowed to connect the wired network while the rest can only access internet.
While the wired network can access all the wireless network.

The new installed PCs now work with DHCP never need to care about the IP when new users come in. Security to a level is in place..... but not 100% will discuss more about this in upcoming posts.