Unused ports on Switch

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Apr 10th, 2009
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I know my question might seem very simple

Why is it suggested to shutdown unused ports on the switch

and also unused vlans like vlan 1

How soes it pose a security issue in the network

Please reply

i will appreciate any response

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Overall Rating: 4 (1 ratings)
Edison Ortiz Fri, 04/10/2009 - 08:57
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- prevents anyone from connecting a switch or hub to your switched network and creating a loop

- prevents any unauthorized workstation from connecting to the network

- add another layer of security

As for the Layer3 Vlans;

- it prevents inadvertently the advertisement of networks

- it preserve switch resources

- another form of network security.




Jon Marshall Fri, 04/10/2009 - 08:59
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Basically if you leave unused ports active someone can wander along to an unused desk etc. and patch in a laptop for example. If you are using DHCP then they would automatically get an IP address.

As for vlans just don't have any unused vlans. Vlan 1 is different. You can't actually shut it down but it is recommended not to have any user ports in vlan 1 as all the management protocols run in this vlan.


gurkamal01 Fri, 04/10/2009 - 09:13
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Thanks for the replies

Q1.So how does vlan hoping happen.

Is it related with vlan 1.

Q2. what can happen if i have any unused vlanlike vlan 202


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