NETGEAR DG834GT manual Ethernet Cabling, Denial of Service Attack, Category 5 Cable Quality

Reference Manual for the Model DG834GT 108 Mbps Super Wireless ADSL Router

Denial of Service Attack

A hacker may be able to prevent your network from operating or communicating by launching a Denial of Service (DoS) attack. The method used for such an attack can be as simple as merely flooding your site with more requests than it can handle. A more sophisticated attack may attempt to exploit some weakness in the operating system used by your router or gateway. Some operating systems can be disrupted by simply sending a packet with incorrect length information.

Ethernet Cabling

Although Ethernet networks originally used thick or thin coaxial cable, most installations currently use unshielded twisted pair (UTP) cabling. The UTP cable contains eight conductors, arranged in four twisted pairs, and terminated with an RJ45 type connector. A normal straight-through UTP Ethernet cable follows the EIA568B standard wiring as described below in Table B-1

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Table B-1.		UTP Ethernet cable wiring, straight-through
Pin	Wire color		Signal
1	Orange/White		Transmit (Tx) +
2	Orange		Transmit (Tx) -
3	Green/White		Receive (Rx) +
4	Blue
5	Blue/White
6	Green		Receive (Rx) -
7	Brown/White
8	Brown

Category 5 Cable Quality

Category 5 distributed cable that meets ANSI/EIA/TIA-568-A building wiring standards can be a maximum of 328 feet (ft.) or 100 meters (m) in length, divided as follows:

20 ft. (6 m) between the hub and the patch panel (if used)

295 ft. (90 m) from the wiring closet to the wall outlet

Network and Routing Basics B-11

August 2004