You probably have at least one computer networked in your home. Your ISP gives you a router (either DSL or cable) and your computer connects to that router to gain access to the Internet. This is a very basic form of a network. It’s just one computer connected to a router. You could even have several devices in the home connected to this one router.
What makes your network any different than any other network? If you think about your setup, it’s just a bunch of computers that share resources. This type of network topology is a peer-to-peer structure. There isn’t much security, because you don’t need it when the network comprises of your own computers. However, when you own an office, you need security to protect certain sections. You do this with a client-server network. Servers control access and place security on each client computer, printer or other hardware resource.
An Introduction to a Windows Domain
The type of client-server network you implement depends on your operating system. Windows environments are called domains. The server runs the Windows Server operating system, and the client computers run client operating systems such as Windows 7, Vista or Windows 8. The first Windows domain was Windows NT and 3.11 client machines.
The Windows Server software controls the domain. The primary domain controller keeps track of all network resources. Each user and client computer is controlled on the domain controller using Active Directory (AD). AD was first introduced in Windows 2000 and it’s still a part of the latest server operating system, which is Windows 2012.
Even if you have experience working with local peer-to-peer networks, there is a bit of a learning curve when you need to configure and maintain a Windows domain. Windows also uses Access Control Lists (ACL) to control client desktop computers. Access Control sets everything from what a user can change on the client computer to what applications the user can access on the desktop.
Client-Server Networks Roles and Groups
The client-server network security is based on roles. Roles define the type of access the user has on the network and if the user can change configurations or users. It’s important that the network administrator keep track of users with elevated roles, because this can lead to a hacked network. It can also lead to some users gaining access to certain documentation and network resources that aren’t supposed to have access.
Most users are placed into a group. These groups are assigned access rights and permissions. Windows includes certain groups as a default after you install the operating system. However, the administrator can make additional groups and assign certain permissions to that group.
The highest level role is the administrator. Windows also has an administrator group. When you install the operating system, you’re asked for an administrator account password. After the installation, you can change the administrator account name, which adds some security to the network. The administrator has full control of the network. This means that no user can lock you out, you have full control of the server and you can configure the network any way you want.
You can also control the way users access files. Access control rights include view, edit, create and full control. This list of security protects documentation and directories. For instance, if you give a user view access to a file, they can view the file’s content but they can’t edit the file’s content. Full control lets the user view and edit the file as well as change the security settings on the file.
Types of Servers on Your Network
You can configure several types of servers on your network. They don’t all need to be physical machines either. You can have virtual machines that host several types of applications, except take note that virtual machines still share physical resources on the server including the hard drive, CPU and memory.
The first common server type is an application server. An application server hosts executable files users can either run directly from the server’s hard drive or download to the local computer’s directory. The application also hosts updates that developers promote and distribute to each client computer. With cloud applications becoming more popular, application servers are slowly being replaced. They are still popular with proprietary client computer applications and legacy software.
File servers are also common in enterprise networks. File servers allow users to upload documents. As a network administrator, you give each user their own directory, so only that particular user can access files contained within. When you centralize where users store files, you can not only control security and access to those files, you can also make it easier to create backups. With a central file server, all you need to do is back up that particular server’s hard drive.
Web servers are probably the most popular servers known even to new network administrators. Web servers can host a public website or an intranet. Intranets are web servers that are only accessible to internal employees. These servers make it easier to disseminate company documents and give you the ability to automate certain HR and administrative tasks. You probably already know what a public-facing web server offers.
These three server types are probably the most common ones you’ll come across while you learn computer networking. However, you might run into other types. DHCP servers control IP assignments. Routers can also serve as DHCP (dynamic host configuration protocol) servers, but bigger enterprise networks often use a physical machine. DNS is another type of server. You can use your ISP’s DNS servers, but bigger networks often have their own DNS servers. These name servers translate a friendly domain name to an IP address for users’ browsers. For instance, if you have an intranet server set up, you probably want a DNS server also configured so that users can type a friendly name into a browser to access the main company intranet site.
When Do You Know It’s Time for a Client-Server Network Setup?
If you already have a small network set up, it’s hard to decide when to make the move to a client-server architecture. It’s more expensive, takes up more resources, and it guarantees some downtime for users as you add the servers, change client settings and get some of the bugs off the network. However, when you need better security and resources, it’s time to make the move.
Consider the cost before you switch and if you have time to manage the network. A client-server network usually requires someone full time to maintain it. You also need to buy the hardware to support the architecture. Enterprise operating systems and software is usually more expensive, especially if you decide to work with a Windows domain.
You don’t have to work with Windows. Linux is also a common environment, but it’s usually considered a more difficult environment to work with if you are new to networking. You can also have a heterogeneous environment, which means that the network has multiple operating systems. For instance, you can have a Windows domain that also has Linux and Mac client computers that connect to it.
Make sure you understand the changes you make to the network, so you’re able to not only manage resources but quickly identify issues when something goes wrong. A client-server network is much more scalable and useful for the enterprise, but it can be frustrating if you don’t know how to work with it.