After you have a software plan in place, you can begin designing a network hardware topology that provides sufficient network resources for your applications.
Many networks grow without proper planning. As the business grows, they become unmanageable and suffer from performance problems. Networks that are not properly planned can lack the scalability that allows them to grow without adversely affecting future business needs. Adequate network design can enable sufficient performance, availability, and security. In the process, you can provide enough information and transaction processing for all of your users.
These checklists help you make planning decisions and begin designing a network that fits your needs.
| Before you begin | |
|---|---|
| __ | Review Network communications to coordinate information gathering that pertains to the communications infrastructure at your site. |
| __ | Create a list of users that need network access. |
| __ | Develop a list of servers that need network connections. |
| Network hardware planning tasks | |||
|---|---|---|---|
| __ | Determine the number of host
machines You need to develop a list of host machines for your networks to support. Host machines are user workstations that connect to networks. Each host machine needs a unique IP address and name. Each host machine also needs access to an appropriate amount of bandwidth to support the applications that are planned for the host machine. |
||
| __ | Plan for types of hosts Your network might contain several types of hosts, including stand-alone, diskless, and dataless hosts. Your network design is affected by your host types. For example, if you have a large number of stand-alone Windows-based PC hosts, you need to take into account server platforms, client protocols, and additional security measures. If you have diskless hosts, some network media not be suitable. |
||
| _ | Plan for network media Network media are the types of connection that make up the network. They include the actual cables as well as the protocols that govern the connections. You have several options in choosing network media, such as Ethernet (fast or Gigabit), token ring, Fiber Distributed Digital Interface (FDDI), Asynchronous Transfer Mode (ATM), wireless technologies, and others. Ethernet is used most often because it is inexpensive and easy to manage, but it carries a performance cost. Mission-critical hosts can connect by using token-ring or FDDI technologies instead of Ethernet to improve performance. ATM is most often used as a backbone technology between different networks because of its unique properties. Choosing your network media is often determined by the balance between performance and availability on one side and cost on the other. To learn more about
how to plan for network media, see the chapter on network infrastructure in IP
Network Design Guide. |
||
| __ | Plan for routers and switches Different subnets or administrative subdivisions within a network can be connected by bridges, hubs, routers, or switches. Bridges and hubs are used sparingly because of their inherent limitations. Routers are most commonly used to connect different domains or subnets within a network because they offer better administrative control over network traffic. However, they can cause performance problems if too many routers exist between hosts. For this reason, switches are often used to speed connections between subnets on a network. Whether you choose a router or a switch to connect network subnets requires careful planning. An adequate plan for routers and switches enables your network to grow with your business without adversely affecting network performance. To learn
how to plan for routers, see the chapter about routing and design in the IP
Network Design Guide. |
||
| __ | Create a network topology After you have determined the components of your network, you need to develop a network topology. The two main types of typology are flat and hierarchical networks. Unless your network is quite small, you will most likely create a hierarchical network, which resembles an inverted tree with the root or trunk at the top and the nodes of the network (or hosts) connected by branches at the bottom. Your topology should schematically itemize all of the physical cables and connections of the hardware that is connected to the network. It should include the types of hosts, network media, hubs, bridges, routers, switches, and servers. To learn more about how to design a network topology,
see the IP Network Design Guide. |
||
When you have completed these tasks, you should have a networking hardware plan that identifies these elements:
| __ | Record a topology of your network. |
| __ | Record a list of hardware, such as network hosts, interface cards, and cables, that you need to implement the topology. |