CimmerianX and nuwan4u are mostly correct. There are a number of factors that limit the length of a single ethernet link, and the default max (IEEE standards) for a cat-5 to cat-7 cable is 100 meters. The main issue is not only signal attenuation at distances beyond that, but the amount of time the signal requires to traverse the distance. You might get longer distances by using specialized end-point electronics (balanced line drivers with cat-7 cable may get you 150 meters). In any case, if you have to go beyond 100M, you are advised to use optical connections and cable. Honestly, optical cables and hardware will probably be more cost-effective these days than cat-6 cables w/ line drivers + the required repeaters. IE, get a switch at each end that has a fiber-optic connection for switch-to-switch connectivity, and the requisite fiber cable. These days, a fiber cable will probably be cheaper than a copper twisted-pair trunk.
I have searched and bought 1000ft Cat6 plenum bare copper cable from 1000ft cables and there are specs of cat6 plenum bare copper cable
Superb quality Cat6 Plenum Bare Copper cable with enhanced audio/video, broadband and security capabilities in reel packing box for smooth installation and ideal for network installation for business and home use. Tested to 550 MHz to provide additional performance and bandwidth over and above the basic requirements of Cat6 550 MHz standards.
Ideal for 10Base-T (IEEE 802.3), 100Base-TX (IEEE 802.3u), 1000Base-TX, 100 Vg-Any LAN (IEEE 802.12), Token Ring (IEEE 802.5), TP-PMD (ANSI X3T9.5), 350 Mbps CDDI, ATM 155, and all proposed category 6 requirements for high-speed, full duplex, parallel transmission protocols.
Verified compliant with EIA/TIA /ETL
4-pair (UTP) unshielded twisted pair cable
23 AWG solid bare copper conductor for superior conductivity
Low Smoke, CMP Plenum rated jacket
Cat6 cable is perfect for supporting 10 Gigabit Ethernet. Since technology and values are continuously evolving, Cat 6 is the wisest choice of cable when taking any possible future updates to your network into consideration.