Unmanaged switches — These switches have no configuration interface or options. They are plug-and-play. They are typically the least expensive switches, found in home, SOHO, or small businesses. They can be desktop or rack mounted.
Managed switches — These switches have one or more ways, or interfaces, to modify the operation of the switch. Common management methods include: a serial console or Command Line Interface accessed via telnet or Secure Shell; an embedded Simple Network Management Protocol SNMP agent allowing management from a remote console or management station; a web interface for management from a web browser. Examples of configuration changes that one can do from a managed switch include: enable features such as Spanning Tree Protocol; set port speed; create or modify VLANs, etc.
Two sub-classes of managed switches are marketed today:
Smart (or intelligent) switches — These are managed switches with a limited set of management features. Likewise "web-managed" switches are switches which fall in a market niche between unmanaged and managed. For a price much lower than a fully managed switch they provide a web interface (and usually no CLI access) and allow configuration of basic settings, such as VLANs, port-speed and duplex.[10]
Enterprise Managed (or fully managed) switches - These have a full set of management features, including Command Line Interface, SNMP agent, and web interface. They may have additional features to manipulate configurations, such as the ability to display, modify, backup and restore configurations. Compared with smart switches, enterprise switches have more features that can be customized or optimized, and are generally more expensive than "smart" switches. Enterprise switches are typically found in networks with larger number of switches and connections, where centralized management is a significant savings in administrative time and effort. A Stackable switch is a version of enterprise-managed switch.
Source: http://en.wikipedia.org/wiki/Network_switch
I would explain in more personal detail, but the wiki explains it pretty well.
Page 402 of the manual for the RackSwitch G8052 describes DHCP Snooping, which filters DHCP traffic.
The basic premise is that you flag ports that are allowed to send packets as a DHCP server (DHCPOFFER, DHCPACK), and by default all other ports are only allowed to send client packets (DHCPDISCOVER, DHCPREQUEST).
It appears the syntax is identical to that of Cisco IOS switches, so if you find a tutorial online on how to do it on a Catalyst switch, it will apply to you, too.
The basics are:
- Turn on
ip dhcp snooping
- Turn on
ip dhcp snooping vlan xx for every xx vlan that you want to control DHCP on
- Turn on
ip dhcp snooping trust on any interface that has a DHCP server connected to it, including uplink ports to other switches if that uplink port is how the clients on this switch get DHCP service.
Best Answer
DHCP option 82 is really what you are looking for, assuming you have a DHCP server that supports it. Once you have a DHCP request with the switch / port information in it, assigning an IP to it should be pretty trivial (just matching up the switch / port to what's in your database). Most production networks don't rely on DHCP though, because it's something else that can fail. This might be nice for the initial setup (have the machine pull an IP via DHCP, then configure itself to use that as a static IP), but I wouldn't suggest you try and run servers off of DHCP.