Unmanaged is also called “dumb” such as a “dumb-hub”.
Does nothing just allows all traffic to go all through your network, you have no control.
Managed – allows the SysAdmin to take control of the network, allows ports to talk to other ports or none at all. For example I personally have a USR Total Switch (managed), in my network I have several servers (www/ftp/mail, etc…) all connected to the USR.
I can have them set to where they cannot talk to each other nor are they allowed to talk to my print server or my personal computers, etc…, this is great if ever a hacker would breach a server the rest of my boxes are safe. I have set up if a hacker does breach they would go to a dead end and have no access to nothing. I have TCP/UDP/ICMP Ports choked (turned of or redirected). So yes it does work on OSI Layer 3.
Managed is always best if you can afford it, try eBay for good used equipment.
Jack is right all the up to the point he said a managed switch operates at layer 3. Only layer 3 switches and routers operate at layer 3. Devices that can use routing protocols and control traffic by way of ip address are layer 3 devices.
You can set up a switch to act as multiple switches thus breaking up your broadcast domains. Separating parts of your network. But if you want to allow traffic to cross these separate broadcast domains you will have to route them with either a layer 3 switch or router.
In fact Layer 3 switching is hardware-based routing. The packet forwarding is handled by specialized hardware ASICs (Application-specific Integrated Circuits). The goal is to capture the speed of switching and the scalability of routing. A Layer 3 switch acts on a packet in the same way that a traditional router does.
Also, to be a truly managed switch it should be capable of being a server, client, or transparent in a VTP (VLAN Trunking Protocol) domain.
this was a question i was puzzled with too until recently ... so far i've captured that a "managed" port is a controlled port ... which can be restricted to access other ports of the switch ... is that correct ? howz this done ???? can pass an example of CLI commands ?
an "unmanaged" port is "dumb" ... meaning it functions like a normal port allowing all traffic to pass thru ...
but how do u separate these ports ?
do u need a VLAN to configure managed ports ??
u are right we segregate the ports using VLAN on the switch...
here are a set of commands as an example...
on the global config mode...
interface e0/3 **this is assigning port 3 onto vlan 10**
swicthport access vlan 10
spanning-tree portfast ** this is telling the switch to skip from blocking mode to forwarding mode, instead of listenin n learnin....to increase the rate of convergance**
int e0/4 **this is assigning port 4 on the switch onto vlan 20**
switchport access vlan 20
annd u might want to config a default gateway to the swicth as well jus in case u want to ping it...
global config mode
ip default-gateway 10.1.1.1
ip address 10.1.1.12 255.255.255.0
** theres VLAN1 as deafualt on urswitch....
in fact all the ports are in vlan 1 on ur swicth bey default**
hmm well hope this helps..and if theres any errors in what i have said above:) fire awayyyyy plz