When visiting a site, users may experience a number of problems related to specific hardware factors. The table below lists several possible problems and the hardware that may be responsible for such problems.
|Hardware related problems
|User's computer crashes when accessing website
||Configuration problem with client machine, or browser plug-ins
|User cannot connect to network devices
||Router, NIC or other network HW/SW not configured correctly
|Web Pages download slowly
||1) Client machine has too little memory, 2) Modem is too slow for anticipated downloads,3) Server is overworked insufficient bandwidth problem, 4) Possibly noisy lines
|User receives a browser error message when accessing a site ( Cannot find URL)
||1) Web server is offline 2) Site has moved to another URL, 3) Network at server end is down, 4) Firewall is improperly configured, 5) DNS server is down
|Only part of a file arrives
||1) Network connection between client and server is intermittent or overloaded, 2) Excessive internet traffic at host server
|Video reception is slow or uneven
||1) Modem or T1 connection is too slow, 2) Web server is busy, 3) ISP router is busy, 4) User's PC hardware is insufficient to run video smoothly
|Web pages on intranet appear quickly but custom reports and forms process very slowly
||1) Connection between web server and database server is not configured properly and database server has too many requests at that moment, 2) Possible disk problems on the client's PC
A computer network can be defined as "two or more computers connected by some means through which they are capable of sharing information".
There are many types of networks:
- (LANs) local area networks,
- (WANs) wide area networks,
- (MANs) metropolitan area networks,
- campus area networks (CANs),
- Token Ring networks,
- Fiber Distributed Data Interface (FDDI) networks,
- Asynchronous Transfer Mode (ATM) networks,
- Frame Relay networks,
- T1 networks,
- DS3 networks,
- bridged networks,
- routed networks, and
- point-to-point networks.
If you can remember the program Laplink, which allowed you to copy files from one computer to another over a special parallel port cable, you can consider that connection a network as well. It was not very scalable (only two computers) or very fast, but it was a means of sending data from one computer to another via a connection.
Connection is an important concept and is what distinguishes a sneaker net, in which information is physically transferred from one computer to another via removable media, from a real network. When you insert a USB drive into a computer, there is no indication that the files came from another computer,
since there is no connection. A connection involves a type of addressing or identification of the nodes on the network (even if it is only primary-secondary).
The machines on a network are often connected physically by means of cables. However, wireless networks, which are devoid of obvious physical connections, are connected through the use of radios. Each node on a wireless network has an address. Frames received on the wireless network have a specific source and destination, as with any network.
Networks are often distinguished by their reach. LANs, WANs, MANs, and CANs are all examples of network types defined by their areas of coverage.
LANs are local to a single building or floor.
WANs cover broader areas, and are usually used to connect LANs. WANs can span the globe.
MANs are common in areas where technology like Metropolitan Area Ethernet is possible.
They typically connect LANs within a given geographical region such as a city or town.
A CAN is similar to a MAN, but is limited to a campus (a campus is usually defined as a group of buildings under the control of one entity,
such as a college or a single company).