Home Networking Technologies

Module 4.

LAN Wireless Frequencies

Frequently used in home networks are the unlicensed 2.4GHz and 5GHz ranges. Bluetooth makes use of 2.4GHz, this is limited to low-speed, short-range communications, it has the advantage of being able to talk to many devices at the same time. Other technologies that use these bands are modern wireless LAN technologies that conform to the IEEE 802.11 standards. Unlike Bluetooth, 802.11 devices transmit at a much higher power level.

Wired Network Technology

A few apps still benefit from a wired switch connection. The most common wired protocol is the Ethernet protocol, an Ethernet LAN can connect devices using many different types of wiring media. Directly connected devices use an Ethernet patch cable, normally an unshielded twisted pair. The cables come in various lengths and normally with RJ-45 connectors installed.

Category 5e or CAT-5e is the most common LAN wiring, the cable is 4 pairs of wires, twisted to reduce electrical interference.

Coaxial cable is an inner wire surrounded by a tubular insulating layer, which is then surrounded by a tubular conducting shield, most coax cables also have an external insulating sheath.

Fiber-optic cables can be glass or plastic with a diameter about the same width as a human hair, fiber-optic cables have a very high bandwidth.

Wi-Fi Networks

Standards have been developed to ensure wireless devices can communicate, they specify the RF spectrum used, data rates, and how the info is transmitted. The IEEE 802.11 standard governs WLAN environments. Standards for LANs use the 2.4GHz and 5GHz band. Collectively, these technologies are called Wi-Fi.

802.11 can provide increased throughput based on the wireless environment, if all devices connect with the same 802.11 standard, max speed can be obtained. If an AP is configured to only accept one standard, devices which do not use that standard will not be able to connect. A mixed mode network can include devices which use any existing Wi-Fi standard.

It is important to connect to the appropriate SSID for your network, the SSID is a case-sensitive, alphanumeric string of up to 32 characters and is sent in the header of all frames transmitted over the WLAN.