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I thought the DHCP snooping is configure on access ports that s where usually windows servers(DHCP) are connected to.<br />
<br />
<br />
Cisco has many security features that are not enabled by default but critical:<br />
DHCP Snooping<br />
ARP Inspection<br />
Port Security Violation.<br />
<br />
why are not enabled by default ?<br />

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I thought the DHCP snooping is configure on access ports that s where usually windows servers(DHCP) are connected to.


Cisco has many security features that are not enabled by default but critical:
DHCP Snooping
ARP Inspection
Port Security Violation.

why are not enabled by default ?


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If I understand DHCP Snooping is configured &nbsp;at the global level on the switch then we can select the port where the trusted DHCP server is plugged into, and configure that port as DHCP snooping trust.<br />
In most environment when the first time they set up an access switch they don't configure it for DHCP snooping.<br />
the very rare scenarios they set up DHCP snooping only on the access switch where the trusted DHCP &nbsp;is plugged to.<br />
So what about other access switches? do they need to be configured for DHCP snooping too? if so, why it is not enabled by default by cisco at the first place?<br />
<br />
Thanks<br />
<br />

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If I understand DHCP Snooping is configured  at the global level on the switch then we can select the port where the trusted DHCP server is plugged into, and configure that port as DHCP snooping trust.
In most environment when the first time they set up an access switch they don't configure it for DHCP snooping.
the very rare scenarios they set up DHCP snooping only on the access switch where the trusted DHCP  is plugged to.
So what about other access switches? do they need to be configured for DHCP snooping too? if so, why it is not enabled by default by cisco at the first place?

Thanks



dhcp snooping

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

Switches / Hubs

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.

Routers

The Dynamic Host Configuration Protocol (DHCP) is an auto configuration protocol used on IP networks and an extension of the Bootstrap Protocol. DHCP allows for computers to be configured automatically to communicate with each other over an IP network without the need for manual setup by a network administrator. The implementation of DHCP relies on a DHCP server to hand out network configuration information to DHCP-capable clients that request an IP address (and other information required or useful in communicating with other devices on an IP network). In addition to an IP address, common configuration information served over DHCP includes a default gateway, subnet mask and DNS sever(s).