Your CCNA experiments will contain quite a bit of details about switches, and permanently reason. if you don’t recognize essential switching theory, you could’t configure and troubleshoot Cisco switches, possibly about the CCNA exam or in the true environment. That goes double for trunking!
Trunking is actually enabling two or maybe more switches to speak and mail frames to one another for transmission to distant hosts. There are 2 key trunking protocols that we need to know the small print of for Test accomplishment and actual-world results, but in advance of we get towards the protocols, Enable’s focus on the cables we need.
Connecting two Cisco switches needs a crossover cable. As you realize, you will find 8 wires within an ethernet cable. Inside a crossover cable, 4 of your cables “cross over” from a person pin to a different. For lots of more recent Cisco switches, all you'll want to do to produce a trunk is hook up the switches using a crossover cable. By way of example, 2950 switches dynamically trunk once you link them with the appropriate cable. If you employ the wrong cable, you’ll be there a while!
There are two diverse trunking protocols in use on these days’s Cisco switches, ISL and IEEE 802.1Q, commonly known as “dot1q”. There are 3 major variations in between The 2. Very first, ISL can be a Cisco-proprietary trunking protocol, exactly where dot1q would be the sector typical. (People of you new to Cisco screening ought to become accustomed to http://www.bbc.co.uk/search?q=먹튀검증 the phrases “Cisco-proprietary” and “field standard”.) In case you’re Functioning in a multivendor surroundings, ISL will not be a good selection. And Though ISL is Cisco’s very own trunking protocol, some Cisco switches operate only dot1q.
ISL also encapsulates your complete frame, escalating the community overhead. Dot1q only places a header on the body, and in some situations, doesn’t even do that. There may be much less overhead with dot1q as compared to ISL. That results in the third major distinction, the way in which the protocols operate Using the native vlan.
The native vlan is just the default vlan that change ports are positioned into if they're not expressly positioned into An additional vlan. On Cisco switches, the indigenous vlan is vlan one. (This may be transformed.) If dot1q is functioning, frames that will be sent throughout the trunk line don’t also have a header put on them; the distant change will think that any frame that has no 토토사이트 header is destined for that native vlan.
The situation with ISL is which is doesn’t understand what a native vlan is. Every single frame is going to be encapsulated, whatever the vlan it’s destined for.
Switching theory is a huge section within your CCNA experiments, and it could look frustrating in the beginning. Just split your scientific studies down into smaller sized, much more manageable components, and shortly you’ll begin to see the magic letters “CCNA” powering your title!