Standard Ethernet

[PietroPoliseno27977]

Hi everyone, I read in the official cisco book that IEEE is the institute that defines the type of cabling, link level protocols, speed rules, etc. while, TIA defines quality standards that it assigns, for example, to a UTP cable. On this last point the book is not very clear. Assign for each type of ethernet, for example 10 Base - t, the transmission medium category 3. The questions are three: 1) The quality is not already defined in the IEEE standards specifying the speed? 2) If by quality we don't mean speed what do we mean? 3) Where can I find a site that talks to me about all the categories that TIA has defined?

[luis_cordova · Accepted solution]

Hi @PietroPoliseno27977 

As far as I understand it:

Simply put, IEEE defines the technologies and physical media of a certain standard, such as Ethernet.
The TIA standard defines the minimum requirements for a certain application to function properly.

The quality is not already defined in the IEEE standards specifying the speed?

If by quality we don't mean speed what do we mean?

IEEE defines the speed at which each category can operate, but not the quality that each manufacturer will have.
For example, if I manufacture UTP network cables, I can affirm that these comply with the IEEE Ethernet standard, but who verifies that my cables have the minimum quality to achieve optimal connectivity according to that standard?
This is where the TIA standard comes in, who guarantees that my cables meet the minimum quality.

Where can I find a site that talks to me about all the categories that TIA has defined?

I hope this link is useful to you:

https://web.anixter.com/axecom/axedoclib.nsf/(unid)/637ea5f1057bd31286257186005baa4a/$file/standards_reference_guide.pdf

Regards

[PietroPoliseno27977]

Ok you were clear I wanted to ask you one last question then going back to the TIA when for example it says "ethernet type: 1000 base-T media: TIA CAT5e UTP or better" It means that a switch with 1000 base-T interfaces does not support a cable to 100 or 10 base - T?

[luis_cordova · Accepted solution]

Hi @PietroPoliseno27977 

"ethernet type: 1000 base-T media: TIA CAT5e UTP or better" 

This indicates that this switch complies with the TIA standard to optimally operate with Cat5e or better cables.

If you use 10 or 100 baseT cables, you could have connectivity or bandwidth problems, because you would not be using the recommended cable for it to work optimally.

Regards

[PietroPoliseno27977]

You have been very clear. However I have also just read in the books that the cisco switches are also able to detect the speed of the interfaces that connect to the ports and to be able to negotiate even if half or full duplex as well as to detect if the utp cable is the correct one and in the case in which it does not change the operating logic of the connected cables. However, as a general rule and the answer that interested me to know was precisely the conformity discourse, that is, TIA guarantees compliance and excellent performance if those categories are respected. Thanks again for your availability

[Joseph W. Doherty]

The "quality" of the copper cables has much to do with what data rate can be used over what distance.