Setting up switches with SFP

Posted on 2007-08-04
Last Modified: 2013-11-05
I have noticed that there is quite a bit a latency on my network and I think that it has to do with my switches.  I have 2 Netgear GS724t and 2 GSM7224 switches.  They all have SFP connectors and the GSM7224 switches came with modules for the SFP.  I was thinking that it would be best if I daisy chained them through the SFP to resolve my issues, but I am clueless on how to even install these or where to even get the wire and what wire at that.  Anybody have a clue?
Question by:adrienne73
    LVL 57

    Expert Comment

    How much latency are you talking about?

    How are they connected now?

    Putting them in a daisy chain will create a spanning tree loop and will cause one of the interfaces to be shut down.

    I don't know what you have connected to what, but a tree setup may be better.  One "central/main" switch and all the other switches connected to it.

    SFP will not reduce latency.  Now, SFP are generally used for gigabit connections.  Both your switches are gigabit switches, so the connection you now have between the switch should already be gigabit.  So going from copper gigabit to fiber gigabit will not reduce latency.

    Check the port that you are currently using to make sure they have connected at gigabit and full duplex.


    Author Comment

    I haven't exactly measured the latency, but I do have users experience definite times of slowness.  

    As for the tree setup, that is what I have right now.  If I actually had stackable switches would that have been a better way to go?

    I am not in the vicinity of the switches right now, but will check them tomorrow to see that they are gigabit and full duplex.
    LVL 57

    Accepted Solution

    You need to figure out the latency.  Typically in a switch LAN enviroment latency should be under 1ms.  Even if it went as high as 5 or 10 ms, most users would not notice.

    In my LAN (about 500 desktops and 50 servers) when ever we have slowness, 99.99999% of the time the server is having problems.  Only once were we having "slowness" on the LAN and it was the network.  Even in that case it one accessing servers that were on the same switch.

    The switch had issues and was misconfigured.  All the ports were mistakenly configured as trunks ports and when ever a server was rebooted all of the ports were going through spanning tree learning.  Changed the ports to access mode and problem was resloved.
    LVL 17

    Assisted Solution

    The biggest culprit of latency on a network is a misconfigured switch port for speed and duplex. If the network card in the computer is running at 100/half lets say, and the switch is trying to negotiate 100/full, then the machine will have hundreds of collisions and constantly be retransmitting which would cause the slowness from the end users perspective. Try hard coding spead and duplex settings on the switch and workstion and also any servers that the user is talking to or internet connections that may be plugged into the network and see if there is an improvement. The small form factor SFP uplinks are not going to increase your performance any better, it's just a different way of hooking switches together.
    LVL 1

    Expert Comment

    Question split.

    EE Moderator

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Maximize Your Threat Intelligence Reporting

    Reporting is one of the most important and least talked about aspects of a world-class threat intelligence program. Here’s how to do it right.

    This article will step through configuring a SonicWALL appliance to utilize an internal DHCP server for Global VPN Client (GVC) hosts.  There are times when using an external (external to the SonicWALL) DHCP server, such as Windows Servers, isn’t pr…
    This tutorial will go through the steps required to write a script that will back up the configuration settings of a HP-ProCurve switch. You will need to get the following things to follow this tutorial: Telnet Scripting Tool e.g. TST10.exe …
    Hi everyone! This is Experts Exchange customer support.  This quick video will show you how to change your primary email address.  If you have any questions, then please Write a Comment below!
    Internet Business Fax to Email Made Easy - With eFax Corporate (, you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…

    760 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    13 Experts available now in Live!

    Get 1:1 Help Now