INTELLIGENT WORK FORUMS
FOR COMPUTER PROFESSIONALS

Log In

Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

New to Datacom, quick question

New to Datacom, quick question

(OP)
Hi everyone,

I have recently moved away from Telecom and am on a new networking team. I have a pretty basic question.

I have a stack of 6 Catalyst switches in an IDF; this IDf services all network connections on the floor. It's VLAN'd out for different purposes (PC's, Printers, servers, etc...).

I need to add 3 PC's into a conference room that only has 1 ethernet port connected back to this IDF. I want to put a switch into this conference room so I can effectively turn the 1 active port into 3. I know I need a crossover cable, but anyone have any ideas on if there is anything else I need to be considering before I do this? Before I start plugging switches into the walls, I want to make sure I am not going to cause some sort of broadcast storm or anything (something I've heard of but haven't quite grasped the concept of yet). Any tips appreciated, I've never done this before...

Thanks all!

RE: New to Datacom, quick question

Crossover cables are only needed at 100 meg and below. The gigabit spec includes Auto-polarity. Many slower switches also have auto-polarity as well.

Broadcast storms may happen if you create a loop, where you only have one cable, it will be harder to make a loop. In an enterprise, I would make that remote switch managed.

I tried to remain child-like, all I achieved was childish.

Tsar of all the Rushers

RE: New to Datacom, quick question

(OP)
Thanks! So do you think I'd create a loop if I do it this way?

RE: New to Datacom, quick question

The potential for a loop exists because end users will have access to switch ports, and could inadvertently (or maliciously) connect two switch ports together. If you have to install a switch, make it a managed switch. This way you can mitigate loops if they occur.

RE: New to Datacom, quick question

(OP)
Thank you!

You mean assign it an IP so I can get to it remotely?

If I attach the switch this way do I have to configure the VLAN's on it, or will it act like a hub where I dont have to configure it?

Much appreciated! This is very different from PBX configs that I'm used to...

RE: New to Datacom, quick question

Yes, managed switches have an IP address, so you can manage them, mostly they have a web page, some may still use telnet.

If your users need to be in separate VLANs, you need a VLAN aware switch (most managed switches have VLANs) Should all 3 PCs belong to the same VLAN, you do not to set up VLANs on this switch, just the port from the IDS switch.

I tried to remain child-like, all I achieved was childish.

Tsar of all the Rushers

RE: New to Datacom, quick question

(OP)
Thank you!!!! :)

RE: New to Datacom, quick question

Since all you need to do is connect 3 PCs to a single jack a managed switch is overkill.

Since there is only one network jack in the room as long as you don't take a long cable and connect this new switch to a network jack in another room there won't be a problem. In any case your existing switches likely do spanning tree (STP) and unless that is turned off for the port going to the conference room STP will prevent looping.

Most newer switches have Auto-MDIX (automatic crossover of Tx/Rx pairs). If the link light on the connection to the existing network jack lights up you should be good to go. Auto-polarity is a different thing.

I like managed switches but for this application I'd get as small a switch as possible. Likewise implementing a VLAN this close to an endpoint yields little advantage. A under $50 5 port switch from a office supply store will do the trick. If it quits working cycle power and if it still doesn't work get another one. Buy bonds with the money you save...

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members!

Resources

Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close